tag:theconversation.com,2011:/africa/topics/carbon-dioxide-removal-19169/articles
Carbon dioxide removal – The Conversation
2023-12-13T19:00:23Z
tag:theconversation.com,2011:article/219753
2023-12-13T19:00:23Z
2023-12-13T19:00:23Z
The COP28 climate agreement is a step backwards on fossil fuels
<p>The COP28 climate summit in Dubai has adjourned. The result is “<a href="https://www.cop28.com/en/">The UAE consensus</a>” on fossil fuels. </p>
<p>This text, agreed upon by delegates from nearly 200 countries, calls for the world to move “away from fossil fuels in energy systems in a just, orderly and equitable manner”. Stronger demands to “phase out” fossil fuels were ultimately unsuccessful.</p>
<p>The agreement also acknowledges the need to phase down “unabated” coal burning and transition towards energy systems consistent with net zero emissions by 2050, while accelerating action in “the critical decade” of the 2020s. </p>
<p>As engineers and scientists who research the necessary changes to pull off this energy system transition, we believe this agreement falls short in addressing the use of fossil fuels at the heart of the climate crisis. </p>
<p>Such an approach is inconsistent with the scientific consensus on the urgency of drastically reducing fossil fuel consumption to limit global warming to 1.5°C.</p>
<figure class="align-center ">
<img alt="A power plant emitting smoke and steam." src="https://images.theconversation.com/files/565543/original/file-20231213-17-62e61q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/565543/original/file-20231213-17-62e61q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/565543/original/file-20231213-17-62e61q.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/565543/original/file-20231213-17-62e61q.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/565543/original/file-20231213-17-62e61q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/565543/original/file-20231213-17-62e61q.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/565543/original/file-20231213-17-62e61q.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Fossil fuel use is at the heart of the climate crisis.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/power-plant-emitin-smoke-steam-1555865300">Peter Gudella/Shutterstock</a></span>
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<h2>‘Abated’ v ‘unabated’</h2>
<p>The combustion of coal, oil and gas <a href="https://www.un.org/en/climatechange/science/causes-effects-climate-change#:%7E:text=Fossil%20fuels%20%E2%80%93%20coal%2C%20oil%20and,they%20trap%20the%20sun's%20heat.">accounts</a> for 75% of all global warming to date – and 90% of CO₂ emissions.</p>
<p>So what does the text actually ask countries to do with these fuels – and what loopholes might they exploit to continue using them well into the future?</p>
<p>Those countries advocating for the ongoing use of fossil fuels made every effort to add the term “unabated” whenever a fossil fuel phase-down or phase-out was proposed during negotiations. </p>
<p>“Abatement” in this context typically means using carbon capture and storage technology to stop CO₂ emissions from engines and furnaces reaching the atmosphere.</p>
<p>However, there is no clear definition of what abatement would entail in the text. This ambiguity allows for a broad and easily abused interpretation of what constitutes “abated” fossil fuel use.</p>
<p>Will capturing 30% or 60% of CO₂ emissions from burning a quantity of coal, oil or gas be sufficient? Or will fossil fuel use only be considered “abated” if 90% or more of these emissions are captured and stored permanently along with low leakage of “fugitive” emissions of the potent greenhouse gas methane, which can escape from oil and gas infrastructure?</p>
<p>This is important. Despite the agreement supposedly honouring “the science” on climate change, low capture rates with high residual and fugitive emissions are inconsistent with what research has shown is necessary to limit global warming to the internationally agreed guardrails of 1.5°C and 2°C above pre-industrial temperatures. </p>
<p>In a 2022 <a href="https://www.ipcc.ch/report/sixth-assessment-report-working-group-3/">report</a>, the Intergovernmental Panel on Climate Change (IPCC) indicated that almost all coal emissions and 33%-66% of natural gas emissions must be captured to be compatible with the 2015 Paris agreement. </p>
<p>That’s assuming that the world will have substantial means of sucking carbon (at least several billion tonnes a year) from the air in future decades. If these miracle machines fail to materialise, our research indicates that carbon capture would need to be <a href="https://papers.ssrn.com/sol3/papers.cfm?abstract_id=4574502">near total on all fuels</a>.</p>
<p>The fact that the distinction between “abated” and “unabated” fossil fuels has not been clarified is a missed opportunity to ensure the effectiveness of the Dubai agreement. This lack of clarity can prolong fossil fuel dependence under the guise of “abated” usage. </p>
<p>This would cause wider harm to the transition by allowing continued investment in fossil fuel infrastructure – new coal plants, for instance, as long as some of the carbon they emit is captured (abated) – thereby diverting resources from more sustainable power sources. This could hobble COP28’s other goal: to triple renewable energy capacity by 2030.</p>
<p>By not explicitly defining these terms, COP28 missed the chance to set a firm, scientifically-backed benchmark for future fossil fuel use.</p>
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<img alt="A solar power farm against a clear blue sky." src="https://images.theconversation.com/files/565542/original/file-20231213-19-gml4jo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/565542/original/file-20231213-19-gml4jo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=385&fit=crop&dpr=1 600w, https://images.theconversation.com/files/565542/original/file-20231213-19-gml4jo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=385&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/565542/original/file-20231213-19-gml4jo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=385&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/565542/original/file-20231213-19-gml4jo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=484&fit=crop&dpr=1 754w, https://images.theconversation.com/files/565542/original/file-20231213-19-gml4jo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=484&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/565542/original/file-20231213-19-gml4jo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=484&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Tripling renewable capacity by 2030 would require an annual growth rate of 17%.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/photovoltaics-solar-power-station-526996462">Soonthorn Wongsaita/Shutterstock</a></span>
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<h2>The coming age of carbon dioxide removal</h2>
<p>Since the world is increasingly likely to overshoot the temperature goals of the Paris agreement, we must actively remove more CO₂ from the atmosphere – with reforestation and direct air capture (DAC), among other methods – than is emitted in future.</p>
<p>Some carbon removal technologies, such as DAC, are very early in their development and scaling them up to remove the necessary quantity of CO₂ will be difficult. And this effort should not detract from the urgent need to reduce emissions in the first place. This balanced approach is vital to not only halt but reverse the trajectory of warming, aligning with the ambitious goals of the Paris agreement.</p>
<p>There has only really been one unambiguously successful UN climate summit: Paris 2015, when negotiations for a top-down agreement were ended and the era of collectively and voluntarily raising emissions cuts began.</p>
<p>A common commitment to “phase down and then out” clearly defined unabated fossil fuels was not reached at COP28, but it came close with many parties strongly in favour of it. It would not be surprising if coalitions of like-minded governments proceed with climate clubs to implement it.</p>
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<img alt="Imagine weekly climate newsletter" src="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p><strong><em>Don’t have time to read about climate change as much as you’d like?</em></strong>
<br><em><a href="https://theconversation.com/uk/newsletters/imagine-57?utm_source=TCUK&utm_medium=linkback&utm_campaign=Imagine&utm_content=DontHaveTimeTop">Get a weekly roundup in your inbox instead.</a> Every Wednesday, The Conversation’s environment editor writes Imagine, a short email that goes a little deeper into just one climate issue. <a href="https://theconversation.com/uk/newsletters/imagine-57?utm_source=TCUK&utm_medium=linkback&utm_campaign=Imagine&utm_content=DontHaveTimeBottom">Join the 20,000+ readers who’ve subscribed so far.</a></em></p>
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<p class="fine-print"><em><span>Alaa Al Khourdajie is a lead author of UNEP's Global Environment Outlook, 7th Edition and a guest research scholar at the International Institute for Applied System Analysis, Austria.</span></em></p><p class="fine-print"><em><span>Lars J Nilsson is a passive member of the World Wild Fund for Nature (WWF) and the Swedish Association for the Conservation of Nature.</span></em></p><p class="fine-print"><em><span>Chris Bataille does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>
The distinction between ‘abated’ and ‘unabated’ fossil fuels is crucial, yet remains ambiguous.
Alaa Al Khourdajie, Research Fellow, Department of Chemical Engineering, Imperial College London
Chris Bataille, Adjunct Research Fellow in Energy and Climate Policy, Columbia University
Lars J Nilsson, Professor of Environmental and Energy Systems Studies, Lund University
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/205543
2023-11-06T07:55:05Z
2023-11-06T07:55:05Z
Abandoned oil rigs could scrape carbon from the sky and store it in empty undersea reservoirs
<figure><img src="https://images.theconversation.com/files/554021/original/file-20231016-19-91k6p2.jpg?ixlib=rb-1.1.0&rect=0%2C489%2C5351%2C3073&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">An oil rig graveyard in Cromarty Firth, Scotland.</span> <span class="attribution"><a class="source" href="https://www.pxfuel.com/en/free-photo-qpdew">Pxfuel</a></span></figcaption></figure><p>Keeping control of our planet’s thermostat is proving tricky these days. Temperatures are rising slowly, and inaction is proving costly as we awkwardly lurch towards a cleaner future. </p>
<p>Some industries are proving stubbornly difficult to decarbonise, and we are likely to <a href="https://theconversation.com/global-warming-to-bring-record-hot-year-by-2028-probably-our-first-above-1-5-c-limit-205758">miss the key 1.5°C warming target</a>. One response: big machines that suck CO₂ out of the air, also known as direct air capture.</p>
<p>Stemming from something like a realist science-fiction flick, these literal “skyscrapers” act like massive industrial vacuum cleaners. They strip the CO₂ from the air and store it in a secure location for at least 1,000 years. However, there are various problems with these machines, which is why they may be best suited to oil rigs.</p>
<p>The problems are threefold. Even if they were rolled out at a vastly bigger scale, they are still expensive, noisy and a major eyesore, which means they cannot be built where people live. </p>
<p>Also, for these machines to work at their best, they would ideally be powered by renewable energy which is why wind power has been endorsed by leading scientists as the <a href="https://news.climate.columbia.edu/2022/01/28/offshore-wind-farms-could-help-capture-carbon-from-air-and-store-it/">perfect marriage</a> for direct air capture. </p>
<p>On land, wind turbines the size of high-rise buildings have their critics. But offshore, there are no locals to bother and the turbines can produce more energy as the wind supply is more consistent. </p>
<p>There is also an abundance of sites below the sea where oil and gas has been extracted and where CO₂ can now be stored.</p>
<h2>Make use of abandoned oil rigs</h2>
<p>Placing CO₂ scrubbers on abandoned oil rigs and sending them out to sea would allow us to take advantage of this. It would also provide a way to deal with the dozens of abandoned oil rigs that pose a serious issue for the industry as they are expensive to decommission. The UK’s rigs alone could cost an estimated <a href="https://theconversation.com/why-we-should-leave-old-oil-rigs-in-the-sea-and-why-we-dont-145587">£24 billion</a>. </p>
<p>An <a href="https://www.ospar.org/convention">international convention</a> known as Ospar also dictates that such rigs cannot stay in the sea and must be removed. This conflicts with UK policy on the preservation of marine life since the legs of the rig can act as <a href="https://www.outdooralabama.com/saltwater-fishing/artificial-reefs">artificial reefs</a> creating new <a href="https://theconversation.com/how-offshore-structures-serve-up-a-steady-supply-of-fish-for-seabirds-114891">marine habitats</a>. </p>
<p>Taxpayers money that would be spent on decommissioning could instead be diverted towards retrofitting the big rigs with the ability to suck CO₂ from the air. Pipelines between air scrubbing machines and the carbon storage reservoirs can be prohibitively expensive, but would be cheaper in this scenario as most of the pipes already exist. </p>
<p>The rigs possess the capability to store CO₂ using the on-board equipment that was previously used to extract oil and natural gas, except it would, with <a href="https://newatlas.com/environment/project-greensand-denmark-ccs/">minor modifications</a>, be operated in reverse.</p>
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<a href="https://images.theconversation.com/files/554234/original/file-20231017-15-w5co52.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Annotated map of the North Sea." src="https://images.theconversation.com/files/554234/original/file-20231017-15-w5co52.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/554234/original/file-20231017-15-w5co52.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=831&fit=crop&dpr=1 600w, https://images.theconversation.com/files/554234/original/file-20231017-15-w5co52.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=831&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/554234/original/file-20231017-15-w5co52.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=831&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/554234/original/file-20231017-15-w5co52.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1045&fit=crop&dpr=1 754w, https://images.theconversation.com/files/554234/original/file-20231017-15-w5co52.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1045&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/554234/original/file-20231017-15-w5co52.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1045&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">North Sea oil (green) and gas (red) as of 2005. Some of these reservoirs are now empty and could be filled with captured carbon.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:North_Sea_oil_and_gas_fields.svg">wiki / USGS / Gautier, D.L</a></span>
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<p>For now, the returns would be modest. Based on the amount of carbon these machines would typically capture – about 1 million tonnes of CO₂ a year requires machines covering <a href="https://www.wri.org/insights/direct-air-capture-resource-considerations-and-costs-carbon-removal">half a square kilometre</a> – a large oil rig might capture around 65,000 tonnes of CO₂ a year. </p>
<p>This of course isn’t much on a global scale. The UK alone emits <a href="https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1147372/2022_Provisional_emissions_statistics_report.pdf">332 million tonnes</a> annually. But all options are worth trying, and it’s a technology we can expect to improve in coming years.</p>
<p>It may also be possible to extract CO₂ directly from the oceans. Recent research by the <a href="https://news.mit.edu/2023/carbon-dioxide-out-seawater-ocean-decorbonization-0216">Massachusetts Institute of Technology</a> suggests this would actually be far more efficient. Carbon is 100 times more concentrated in seawater than it is in the sky, and this approach could ultimately begin reversing acidification in our oceans.</p>
<p>Rigs that can be moved to other sites on demand would be the perfect candidates, as the same rig could store CO₂ in many different sites under the sea. These sites include empty natural gas reservoirs and underground rivers, and it is this flexibility that could finally resolve the ongoing stalemate between the Ospar convention and the UK government.</p>
<p>The industry is still too small to deliver carbon removal on anything like the required scale. This is due to a lack of investment, and a very minimal market presence. </p>
<p>But, much like how the vaccines for COVID quickly matured due to the absolute necessity of the global pandemic, we now also require a significant mass investment to generate our own market that allows us to remove carbon. The US company Frontier, backed by tech giants, is providing <a href="https://finance.yahoo.com/news/google-facebook-owners-among-tech-093000062.html">US$925 million (£738 million)</a> in order to stimulate such a market into existence. </p>
<p>Unfortunately, even this only represents between <a href="https://nanransohoff.com/A-mental-model-for-combating-climate-change-846be1769d374fa1b5b855407c93da66">0.1% and 1%</a> of the total finances required every year up until 2050. That’s because, even in an optimistic scenario where renewables grow and global emissions are reduced, we’ll still need to remove 10 billion tonnes of carbon to compensate for the fact that industries like steel and cement are notoriously hard to decarbonise.</p>
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<img alt="Imagine weekly climate newsletter" src="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p><strong><em>Don’t have time to read about climate change as much as you’d like?</em></strong>
<br><em><a href="https://theconversation.com/uk/newsletters/imagine-57?utm_source=TCUK&utm_medium=linkback&utm_campaign=Imagine&utm_content=DontHaveTimeTop">Get a weekly roundup in your inbox instead.</a> Every Wednesday, The Conversation’s environment editor writes Imagine, a short email that goes a little deeper into just one climate issue. <a href="https://theconversation.com/uk/newsletters/imagine-57?utm_source=TCUK&utm_medium=linkback&utm_campaign=Imagine&utm_content=DontHaveTimeBottom">Join the 20,000+ readers who’ve subscribed so far.</a></em></p>
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<p class="fine-print"><em><span>Ben Kolosz does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>
This could be one reason to leave these rigs in the sea.
Ben Kolosz, Lecturer (Assistant Professor) of Renewable Energy and Carbon Removal, University of Hull
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/212462
2023-09-22T00:47:18Z
2023-09-22T00:47:18Z
Carbon removal: why ambitious ‘no nonsense’ plans are vital to limit global heating to 2°C
<p>2023 is proving to be a year of climate and weather extremes. Record-busting <a href="https://climate.copernicus.eu/summer-2023-hottest-record">global air and ocean temperatures</a>, unprecedented <a href="https://theconversation.com/devastatingly-low-antarctic-sea-ice-may-be-the-new-abnormal-study-warns-212376">low levels of Antarctic sea ice</a>, and devastating <a href="https://apnews.com/article/photography-wildfires-climate-fire-greece-hawaii-spain-canada-22266a7cc68dd98c8753a8fe8b72c109">fires</a> and <a href="https://www.yahoo.com/news/ten-countries-territories-saw-severe-003606452.html?guccounter=1&guce_referrer=aHR0cHM6Ly93d3cuZ29vZ2xlLmNvbS8&guce_referrer_sig=AQAAAKeR6ATk1c6Z6l668WsxKzUzLhqD2KEEK-c8XWVq0CttFZETnIG-H4XgGzycJmtWLtrHPH0bKGGV7vQuknlT7HqAKktEFyU6fhMhpK1JfGYJlmvI5i7H3bjRaiLOefRqpW6wLpH1KHx23nG-49XnoxEjd40ItUGcCkJ9OmKMi_ej">floods</a> have been reported across the world. </p>
<p>Less discussed by the world media is the continuing rise in atmospheric greenhouse gases driving these changes. Carbon dioxide (CO₂) is <a href="https://www.noaa.gov/news-release/broken-record-atmospheric-carbon-dioxide-levels-jump-again">at a level</a> not seen since the hothouse world of the <a href="https://mashable.com/article/carbon-dioxide-earth-co2">Pliocene</a>, 3 million years ago. On top of that, an <a href="http://www.bom.gov.au/climate/enso/">El Niño event is now likely</a>, so widespread extreme events may <a href="https://www.axios.com/2023/09/17/el-nino-ciimate-change-extreme-weather">intensify in coming months</a>. </p>
<p>Despite the changes we are seeing, global efforts to cut emissions <a href="https://www.carbonbrief.org/guest-post-what-credible-climate-pledges-mean-for-future-global-warming/">fall well short</a> of what’s needed to keep heating to less than 2°C, let alone the more ambitious Paris Agreement target of 1.5°C. This creates an urgent need for the purposeful removal of atmospheric CO₂ as well as cuts in emissions.</p>
<p>In a <a href="https://www.nature.com/articles/d41586-023-02649-8">recent article in Nature</a>, we argue for a different approach to pricing carbon. It should take into account how it is removed from the atmosphere, for how long, and with what confidence. This will help fund the most promising technologies for reaching net-zero carbon emissions by 2050.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/devastatingly-low-antarctic-sea-ice-may-be-the-new-abnormal-study-warns-212376">Devastatingly low Antarctic sea ice may be the ‘new abnormal', study warns</a>
</strong>
</em>
</p>
<hr>
<h2>Carbon removal is on the agenda</h2>
<p>The United Nations hosted a “no-nonsense” <a href="https://www.un.org/en/climatechange/climate-ambition-summit">Climate Ambition Summit</a> in New York this week with the aim of accelerating the global transition away from carbon. This must be done to avoid breaching 2°C of global heating relative to the pre-industrial era. </p>
<p>Two strategies are being pursued: </p>
<ol>
<li>carbon emission reductions</li>
<li>carbon dioxide removal (CDR), also called “negative emissions”.</li>
</ol>
<p>At <a href="https://www.un.org/en/climatechange/cop26">COP26</a> in 2021, global resolutions on cutting emissions drove the push for “<a href="https://theconversation.com/net-zero-carbon-neutral-carbon-negative-confused-by-all-the-carbon-jargon-then-read-this-151382">net zero</a>” across nations, cities and sectors. However, some worldwide activities, including aviation and heavy industry, face challenges eliminating emissions. Carbon credits have become the main way to offset their remaining emissions.</p>
<p>The dilemma lies in the nature of carbon credits. Most are allocated for so-called “avoidance” measures. A prime example is not clearing forest, which has come <a href="https://theconversation.com/worthless-forest-carbon-offsets-risk-exacerbating-climate-change-211862">under intense scrutiny</a>. </p>
<p>And these measures do nothing about the existing excess carbon dioxide. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/worthless-forest-carbon-offsets-risk-exacerbating-climate-change-211862">'Worthless' forest carbon offsets risk exacerbating climate change</a>
</strong>
</em>
</p>
<hr>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1704156181256679842"}"></div></p>
<p>A big change in our thinking is needed. The emphasis must shift from emission “avoidance” to “removal” offsets that actively pull carbon from the atmosphere. So how do we tackle the monumental challenge of reducing atmospheric CO₂? </p>
<p>What’s needed is a shift from avoidance to verifiable <a href="https://www.ipcc.ch/report/ar6/wg3/downloads/outreach/IPCC_AR6_WGIII_Factsheet_CDR.pdf">carbon dioxide removal</a>. Almost all current removal efforts come from traditional land management. Less than 1% comes from innovative removal technologies. </p>
<p>Removal technologies include:</p>
<ul>
<li><a href="https://drawdown.org/solutions/biochar-production">biochar</a> – where carbon from plant material is sequestered as charcoal and stored in soil</li>
<li><a href="https://www.iea.org/energy-system/carbon-capture-utilisation-and-storage/direct-air-capture">direct air carbon capture and storage (DACCS)</a> – which directly removes CO₂ from the air and stores it in geological formations.</li>
</ul>
<p>A major advance at COP26 was to work out the projected demand and market trajectory for carbon offsets. Offset credits play a vital role in advancing CO₂ removal technologies and developing carbon markets. </p>
<p>Another key goal was to formulate a carbon trading rulebook. The resulting <a href="https://www.iif.com/tsvcm">Taskforce on Scaling Voluntary Carbon Markets</a> predicts demand for carbon offsets will grow tenfold by 2030 and 50-fold by 2050.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/stripping-carbon-from-the-atmosphere-might-be-needed-to-avoid-dangerous-warming-but-it-remains-a-deeply-uncertain-prospect-195097">Stripping carbon from the atmosphere might be needed to avoid dangerous warming – but it remains a deeply uncertain prospect</a>
</strong>
</em>
</p>
<hr>
<h2>So what are the obstacles?</h2>
<p>We identify a potential bottleneck. Developing, testing and scaling up CO₂ removal technologies takes time. This means a lag in supply could stymie the rapidly growing demand for carbon dioxide removal. </p>
<p>Another problem is that the current carbon offset market offers a flat rate, no matter the quality or effectiveness of the CO₂ removal method. There is an urgent need for a tiered market that values high-quality, proven CO₂ removal methods. This will provide an incentive to fast-track their use.</p>
<p>The <a href="https://unfccc.int/about-us/regional-collaboration-centres/the-ciaca/about-carbon-pricing#What-does-the-Paris-Agreement-say-on-carbon-pricin">carbon offset market’s pricing mechanism</a> is a stumbling block. The price for offsetting a tonne of CO₂ is in the range US$10–100. Cheaper avoidance strategies, such as not clearing forests, heavily influence this price. </p>
<p>The existing pricing falls short when we consider the costs of CO₂ removal technologies, which can exceed US$200 per tonne removed.</p>
<p>The prevailing metric, simplifying everything to “one tonne of carbon”, doesn’t consider the complexities of CO₂ removal. Each method has its own specifics about how long it can store carbon, how reliably it can be verified and the potential risks or side effects. Shoehorning such a varied field into a single metric stifles innovation in CO₂ removal.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1704521540157448678"}"></div></p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/net-zero-by-2050-too-late-australia-must-aim-for-2035-213973">Net zero by 2050? Too late. Australia must aim for 2035</a>
</strong>
</em>
</p>
<hr>
<h2>What are the solutions?</h2>
<p>Understanding the market’s resistance to intricate metrics, we propose a more nuanced yet approachable two-step solution:</p>
<ol>
<li><p><strong>Shift in metrics</strong>: change the standard from a “carbon tonne” to a “carbon tonne year”. This recognises the longevity of CO₂ removal methods and rewards those that store carbon longer. Such a metric connects directly with efforts to cut emissions.</p></li>
<li><p><strong>A mandatory warranty</strong>: each “carbon tonne year” requires a warranty from the seller to vouch for the method’s reliability (verification) and its overall safety (assessing risks and side effects).</p></li>
</ol>
<p>These changes will foster a system that appropriately values CO₂ removal methods that are long-lasting, reliable and safe. It creates an incentive to develop and use these methods.</p>
<p>In our Nature article, we advocate a structured ten-year plan. This timeframe is crucial for maturing the markets, establishing effective regulatory frameworks and fine-tuning verification. </p>
<p>It’s essential to prepare for the evolution and scaling up of carbon dioxide removal. A decade provides a realistic window to develop the processes needed to reach net zero.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/net-zero-carbon-neutral-carbon-negative-confused-by-all-the-carbon-jargon-then-read-this-151382">Net-zero, carbon-neutral, carbon-negative ... confused by all the carbon jargon? Then read this</a>
</strong>
</em>
</p>
<hr>
<p>The magnitude of this task cannot be overstated. In just a few decades, <a href="https://www.unep.org/resources/emissions-gap-report-2022">CO₂ removal must operate on a colossal scale</a>, comparable to global food production.</p>
<p>The New York summit has set the stage for the <a href="https://www.cop28.com/">COP28 meeting in Dubai</a> later this year. An ambitious long-term global strategy can still provide a sustainable future within the heating limits set in the 2015 Paris Agreement. </p>
<p>It’s time to get real about carbon.</p><img src="https://counter.theconversation.com/content/212462/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Chris Turney receives funding from the Australian Research Council. He is a scientific adviser and holds shares in cleantech biographite company, CarbonScape (<a href="https://www.carbonscape.com">https://www.carbonscape.com</a>). Chris is affiliated with the virtual Climate Recovery Institute (<a href="https://climaterecoveryinstitute.com.au">https://climaterecoveryinstitute.com.au</a>).</span></em></p><p class="fine-print"><em><span>Lennart Bach receives funding from the Australian Research Council and the Carbon to Sea Initiative. He is a scientific adviser of Submarine (<a href="https://www.submarine.earth/">https://www.submarine.earth/</a>), which develops tools for monitoring, reporting and verification of marine CO₂ removal. Lennart is affiliated with the virtual Climate Recovery Institute (<a href="https://climaterecoveryinstitute.com.au">https://climaterecoveryinstitute.com.au</a>).</span></em></p><p class="fine-print"><em><span>Philip Boyd receives funding from the Australian Research Council and he is affiliated with the virtual Climate Recovery Institute. </span></em></p>
Global efforts to cut emissions fall well short of what’s needed to avoid dangerous warming. It’s becoming essential to develop carbon-removal strategies to get to net zero.
Christian Turney, Pro Vice-Chancellor of Research, University of Technology Sydney
Lennart Bach, Associate Professor, Institute for Marine and Antarctic Studies, University of Tasmania
Philip Boyd, Professor of Marine Science, Institute for Marine and Antarctic Studies, University of Tasmania
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/207901
2023-06-26T02:55:06Z
2023-06-26T02:55:06Z
NZ’s geothermal wells offer a cheap way of storing carbon permanently – equivalent to taking 600,000 cars off the road
<figure><img src="https://images.theconversation.com/files/533399/original/file-20230622-15-qw5idq.jpg?ixlib=rb-1.1.0&rect=726%2C181%2C8063%2C3423&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock/N.Minton</span></span></figcaption></figure><p>We know putting carbon dioxide (CO₂) into the atmosphere is bad for the climate. But should we be reversing some of the damage by removing greenhouse gases that were emitted decades ago?</p>
<p>The Intergovernmental Panel on Climate Change (<a href="https://www.ipcc.ch/">IPCC</a>) seems to think so. Its <a href="https://www.ipcc.ch/report/sixth-assessment-report-cycle/">latest report</a> highlights CO₂ removal as an essential activity if society wants to avoid warming the climate by 2°C or more.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1511411850616967195"}"></div></p>
<p>This is not <a href="https://ieaghg.org/ccs-resources/what-is-ccs">carbon capture and sequestration</a>, which tries to neutralise the burning of fossil fuels. Nor is it limited to the removals you get by planting – and never harvesting – new forests. Carbon dioxide removal includes all kinds of land- and engineering-based practices that extract the gas from the atmosphere and lock it away permanently.</p>
<p>But it is not an excuse to avoid emissions cuts. Decarbonisation – society’s shift away from fossil fuels – remains essential, and we’re not doing it fast enough.</p>
<p>Atmospheric CO₂ removal – basically, negative emissions – can buy us time to decarbonise by walking back some of the centuries of build-up. And we think New Zealand could be a leader in this effort. </p>
<p>Considering our geothermal and forestry resources, <a href="https://doi.org/10.31223/X52D52">we estimate</a> New Zealand could remove up to three million tonnes of CO₂ from the atmosphere each year – the equivalent of taking 600,000 cars off the road.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/on-top-of-drastic-emissions-cuts-ipcc-finds-large-scale-co-removal-from-air-will-be-essential-to-meeting-targets-180663">On top of drastic emissions cuts, IPCC finds large-scale CO₂ removal from air will be "essential" to meeting targets</a>
</strong>
</em>
</p>
<hr>
<h2>Putting CO₂ into geothermal systems</h2>
<p>When CO₂ is pumped from our cars and smokestacks, it immediately disperses at an extremely low concentration across the vast atmosphere. For every 2,400 molecules making up our air, just one is CO₂ (~420 ppm), which makes it hard to filter them back out again.</p>
<p>Trees extract the few CO₂ molecules from air for photosynthesis. The oceans are also good at removing CO₂ but this makes them more acidic, which is not great for coral reefs.</p>
<p>Scientists have been developing their own technologies for atmospheric CO₂ removal. Most are currently expensive to do in practice. But we think New Zealand could be doing CO₂ removal cheaper than anywhere else in the world, taking advantage of our well developed geothermal and forestry industries.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-nz-could-become-a-world-leader-in-decarbonisation-using-forestry-and-geothermal-technology-182760">How NZ could become a world leader in decarbonisation using forestry and geothermal technology</a>
</strong>
</em>
</p>
<hr>
<p>Over the <a href="https://www.engineeringnz.org/programmes/heritage/heritage-records/wairakei-geothermal-power-development/">past 60 years</a>, we’ve perfected how to extract hot water from several kilometres underground, use it to generate electricity and then put the cooled water back down again. What’s more, the geothermal industry has already done the hard (and <a href="https://www.energymonitor.ai/news/high-upfront-costs-stunt-growth-of-geothermal-in-the-us/">expensive</a>) part to figure out how to capture CO₂ that comes up with the geothermal water and inject it back underground. </p>
<p>Unfortunately, geothermal systems cool down over time. Unless new wells are drilled, they deliver less electricity with each decade they’re in use. We can make up the decline by <a href="https://www.stuff.co.nz/national/gisborne/131593927/the-student-with-a-plan-to-burn-forestry-slash-at-geothermal-plants">burning logs or forestry waste</a> to further heat the geothermal water and generate more power. </p>
<p>This biomass is a good fuel because it is carbon neutral: any CO₂ it emits came from the atmosphere, not underground. And the forestry industry is already there – a supply of logs, transport logistics and know-how – which all helps keep the costs down.</p>
<p>But instead of letting CO₂ from the burned wood go back into the atmosphere, we could <a href="https://www.carbfix.com/how-it-works/">dissolve it in the geothermal water</a> before sending it underground. Unlike in fossil-fuel carbon-capture projects, which inject pure CO₂ that might later rise and leak out, the carbonated water is slightly heavier. </p>
<p>It’s an involved process, but at the end you can turn a geothermal system into a carbon sink that also generates renewable electricity.</p>
<figure class="align-center ">
<img alt="Wairakei geothermal electric power generating station in the Taupo Volcanic Zone in New Zealand" src="https://images.theconversation.com/files/533405/original/file-20230622-27-pbx68s.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/533405/original/file-20230622-27-pbx68s.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/533405/original/file-20230622-27-pbx68s.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/533405/original/file-20230622-27-pbx68s.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/533405/original/file-20230622-27-pbx68s.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/533405/original/file-20230622-27-pbx68s.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/533405/original/file-20230622-27-pbx68s.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">If carbon dioxide from the burning of logs or forestry waste is dissolve in geothermal water, it could then be returned to the well to store the carbon.</span>
<span class="attribution"><span class="source">Shutterstock/Pi-Lens</span></span>
</figcaption>
</figure>
<h2>Decarbonisation on a budget</h2>
<p>When tackling an enormous problem like climate change, governments have to weigh up how much they think <a href="https://en.wikipedia.org/wiki/Overton_window">voters will let them spend</a> to cut emissions. For this, it is helpful to measure decarbonisation costs.</p>
<p>Mostly, emissions reduction is a choice to switch to a newer, cleaner technology.
One <a href="https://www.sciencedirect.com/science/article/pii/S0095069617308392">study on abatement costs</a> estimates that the switch from a petrol to an electric car equates to paying US$700 for each tonne of CO₂ kept out of the atmosphere.</p>
<p>We have recently <a href="https://doi.org/10.31223/X5N66N">calculated the decarbonisation costs</a> for different geothermal technologies. We found switching from natural gas to geothermal electricity costs about US$250 for each tonne of CO₂ not emitted. When you boost geothermal with extra bioenergy and add CO₂ removal, this drops to US$150 a tonne. And if you’ve already paid for the geothermal plant and wells – an advantage we have here in Aotearoa – then it could drop as low as US$55 a tonne. </p>
<p>In terms of buying ourselves out of an emissions liability, geothermal carbon removal is one of the cheapest options out there.</p>
<p>The government may need to <a href="https://www.treasury.govt.nz/sites/default/files/2023-04/cefa23.pdf">pay billions of dollars between now and 2030</a> to meet targets under the Paris agreement. A homegrown carbon-removal industry could end up as a strategic strength, particularly as <a href="https://theconversation.com/cyclone-gabrielle-triggered-more-destructive-forestry-slash-nz-must-change-how-it-grows-trees-on-fragile-land-200059">social licence for clear-felling forestry</a> continues to be eroded.</p>
<h2>Challenges for CO₂ removal</h2>
<p>The main barrier right now is cost. Citing its economic uncertainty, a key UN climate panel has <a href="https://www.axios.com/2023/05/25/united-nations-carbon-removal-critique">come out against engineering-based carbon removals</a>. </p>
<p>But there is cause for optimism here: the recent history of <a href="https://www.irena.org/Data/View-data-by-topic/Costs/Wind-Costs">wind energy</a> and <a href="https://www.iea.org/data-and-statistics/charts/evolution-of-solar-pv-module-cost-by-data-source-1970-2020">solar power</a> shows costs can fall dramatically as technology uptake grows. With our low-cost advantages, New Zealand has an opportunity to accelerate the rest of the world along the CO₂ removal learning curve.</p>
<p>Another concern is that a narrow focus on offsetting emissions could let heavy climate polluters off the hook. This is the tension between gross and net emission reductions. The government is addressing this issue by <a href="https://environment.govt.nz/news/nz-ets-review-consultation-now-open/">reviewing the Emission Trading Scheme</a>, but the world will still need billions of tonnes of CO₂ removal to undo historic damage.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/does-carbon-capture-and-storage-hype-delay-emissions-cuts-heres-what-research-shows-202972">Does carbon capture and storage hype delay emissions cuts? Here's what research shows</a>
</strong>
</em>
</p>
<hr>
<p>Others argue land availability and competition with food crops will limit how much biomass can be made available for carbon removal. While true in a narrow sense, New Zealand currently harvests <a href="https://www.mpi.govt.nz/forestry/forest-industry-and-workforce/forestry-wood-processing-data">tens of millions of tonnes of timber</a> each year while producing <a href="https://www.stuff.co.nz/business/farming/300350351/whos-eating-new-zealand">enough food for 40 million people</a>.</p>
<p>The critics are right to point out this is not a miracle technology. If we’re to undo the climate legacy of centuries of carbon-hungry activity, it’s going to take all kinds of carbon removal. </p>
<p>Other research projects are underway, including the use of a rock known as Dunite, which can be spread on farmland to <a href="https://www.stuff.co.nz/environment/climate-news/129893155/what-is-dunite-the-cup-of-tea-that-led-to-a-nzfirst-experiment">lock up carbon as it weathers</a>, direct capture of CO₂ from the air with the <a href="https://www.stuff.co.nz/environment/climate-news/126685010/new-zealand-company-that-could-revolutionise-carbon-capture-gets-1m-funding">common mineral Olivine</a>, and enhancement of the carbon-storage capacity of marine sediments, <a href="https://www.nature.com/articles/ngeo2421">especially in Fiordland</a>.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/blue-carbon-could-a-solution-to-the-climate-challenge-be-buried-in-the-depths-of-fiords-205639">Blue carbon: could a solution to the climate challenge be buried in the depths of fiords?</a>
</strong>
</em>
</p>
<hr>
<p>A key unknown right now is whether the public wants this. It’s easy to kick the can down the road, and it’s true that international carbon trade is a curly issue that needs rigorous study. But CO₂ removal is not science fiction decades away from maturity. It’s here now.</p><img src="https://counter.theconversation.com/content/207901/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>David Dempsey receives funding from MBIE for geothermal research.</span></em></p><p class="fine-print"><em><span>Rebecca Peer receives funding from MBIE for research on New Zealand's energy future. </span></em></p><p class="fine-print"><em><span>Karan Titus does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>
Most technologies for CO₂ removal are expensive. But New Zealand could be doing this cheaper than other countries, taking advantage of existing geothermal and forestry industries.
David Dempsey, Senior lecturer, University of Canterbury
Karan Titus, PhD Student, University of Canterbury
Rebecca Peer, Lecturer, University of Canterbury
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/202428
2023-04-12T12:10:59Z
2023-04-12T12:10:59Z
In the turbulent Drake Passage, scientists find a rare window where carbon sinks quickly into the deep ocean
<figure><img src="https://images.theconversation.com/files/520309/original/file-20230411-18-wrggfk.jpg?ixlib=rb-1.1.0&rect=274%2C263%2C3123%2C2296&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The Drake Passage, seen from Antarctica, is one of the most turbulent ocean regions on Earth.</span> <span class="attribution"><span class="source">Lilian Dove</span></span></figcaption></figure><p>Looking out across the Southern Ocean near Antarctica, I can see whales and seabirds diving in and out of the water as they feed on sea life in the lower levels of the food web. At the base of this food web are tiny phytoplankton – algae that grow at the ocean surface, taking up carbon from the atmosphere through photosynthesis, just as plants on land do.</p>
<p>Because of their small size, phytoplankton are at the mercy of the ocean’s swirling motions. They are also so abundant that the green swirls are often visible from space. </p>
<p>Typically, phytoplankton remain near the surface of the ocean. Some may slowly sink to depth because of gravity. But in the turbulent Drake Passage, a 520-mile-wide (850 km) bottleneck between Antarctica and South America, something unusual is happening, and it has an impact on how the ocean takes carbon dioxide – the main driver of global warming – out of the atmosphere.</p>
<figure class="align-center ">
<img alt="A satellite image shows green swirls off the South American coast." src="https://images.theconversation.com/files/520127/original/file-20230411-24-4z7ae3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/520127/original/file-20230411-24-4z7ae3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=511&fit=crop&dpr=1 600w, https://images.theconversation.com/files/520127/original/file-20230411-24-4z7ae3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=511&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/520127/original/file-20230411-24-4z7ae3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=511&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/520127/original/file-20230411-24-4z7ae3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=643&fit=crop&dpr=1 754w, https://images.theconversation.com/files/520127/original/file-20230411-24-4z7ae3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=643&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/520127/original/file-20230411-24-4z7ae3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=643&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A satellite image captures a green phytoplankton bloom off the coast of Argentina. The Drake Passage is at the country’s southern end.</span>
<span class="attribution"><a class="source" href="https://oceancolor.gsfc.nasa.gov/gallery/612/">NASA Aqua/MODIS</a></span>
</figcaption>
</figure>
<h2>The Drake Passage</h2>
<p>The Drake Passage is notorious for its violent seas, with waves that can top 40 feet (12 meters) and <a href="https://doi.org/10.1038/s43247-022-00644-x">powerful converging currents</a>, some flowing as fast as <a href="https://doi.org/10.1002/2016GL070319">150 million cubic meters per second</a>. Cold water from the Southern Ocean and warmer water from the north collide here, spinning off <a href="https://doi.org/10.1175/JPO-D-18-0150.1">powerful and energetic eddies</a>.</p>
<p>New scientific research I am involved in <a href="https://scholar.google.com/citations?user=AlCIFFYAAAAJ&hl=en">as an oceanographer</a> now shows how the Drake Passage and a few other specific areas of the Southern Ocean play an outsize role in how the oceans lock up carbon from the atmosphere.</p>
<figure class="align-center ">
<img alt="A map shows the underwater ridges and continental shelves." src="https://images.theconversation.com/files/520123/original/file-20230411-22-3zv2hv.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/520123/original/file-20230411-22-3zv2hv.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=559&fit=crop&dpr=1 600w, https://images.theconversation.com/files/520123/original/file-20230411-22-3zv2hv.PNG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=559&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/520123/original/file-20230411-22-3zv2hv.PNG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=559&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/520123/original/file-20230411-22-3zv2hv.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=702&fit=crop&dpr=1 754w, https://images.theconversation.com/files/520123/original/file-20230411-22-3zv2hv.PNG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=702&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/520123/original/file-20230411-22-3zv2hv.PNG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=702&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A topographic map of the Drake Passage between South America and Antarctica.</span>
<span class="attribution"><a class="source" href="https://www.ncei.noaa.gov/products/etopo-global-relief-model.">NCEI/NOAA</a></span>
</figcaption>
</figure>
<p>That process is crucial for our understanding of the climate. The global ocean is a massive reservoir of carbon, holding over <a href="https://science.nasa.gov/earth-science/oceanography/ocean-earth-system/ocean-carbon-cycle">50 times as much carbon</a> as the atmosphere. However, it is only when water carrying carbon <a href="https://doi.org/10.1029/2020GB006790">gets to the deep ocean</a> that carbon can be stored for long periods – up to centuries or millennia.</p>
<p>Photosynthetic phytoplankton are at the heart of that exchange. And in the Drake Passage, my colleagues and I have found that undersea mountains are stirring things up.</p>
<h2>The role of ocean layers</h2>
<p>The ocean can be visualized as having layers. With constant surface waves and winds, the upper layer is always stirring around, mixing waters. It’s like mixing milk into your morning coffee. This stirring <a href="https://doi.org/10.1038/s41467-020-18203-3">mixes in solar heat and gases</a>, such as carbon dioxide, taken up from the atmosphere.</p>
<p>Water density generally increases as the waters get deeper and colder and saltier. That forms density layers that are typically flat. Since water prefers to keep its density constant, it mostly moves horizontally and doesn’t easily move between the surface and deep ocean.</p>
<figure class="align-center ">
<img alt="A graphic shows the typical ocean density layers, with phytoplankton in the upper layers." src="https://images.theconversation.com/files/520160/original/file-20230411-24-1kv12p.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/520160/original/file-20230411-24-1kv12p.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=485&fit=crop&dpr=1 600w, https://images.theconversation.com/files/520160/original/file-20230411-24-1kv12p.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=485&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/520160/original/file-20230411-24-1kv12p.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=485&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/520160/original/file-20230411-24-1kv12p.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=610&fit=crop&dpr=1 754w, https://images.theconversation.com/files/520160/original/file-20230411-24-1kv12p.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=610&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/520160/original/file-20230411-24-1kv12p.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=610&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">In most of the ocean, water stays within a density layer and doesn’t mix with colder, saltier water.</span>
<span class="attribution"><span class="source">Lilian Dove</span></span>
</figcaption>
</figure>
<p>Yet despite this physical barrier, water testing shows that carbon dioxide produced by human activities is making its way into the deep ocean. One way is through chemistry: Carbon dioxide dissolves in water, creating carbonic acid. Living creatures in the ocean are another.</p>
<h2>A view into the Drake Passage</h2>
<p>Oceanographers have long pointed to the north Atlantic Ocean and the Southern Ocean as places <a href="https://www.jstor.org/stable/24862019">where surface waters are moved to depth</a>, taking large volumes of carbon with them. However, recent work has shown that this process may actually be dominated by only a few areas – <a href="https://doi.org/10.1029/2022GL102550">including the Drake Passage</a>.</p>
<p>Despite its being one of the most famous stretches of the ocean, scientists have only recently been able to observe this window in action.</p>
<p>The main flow of the Drake Passage is created by the effect of strong westerly winds across the Southern Ocean. Scientists have found that the westerly winds create a slope in the water density, with dense waters shallower closer to Antarctica, where colder melt water caps the surface, but sloping deeper into the ocean farther north toward South America.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/520164/original/file-20230411-26-mi0289.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Side-by-side graphics show (1) the typical ocean density layers and (2) the sloped density layers in the Drake Passage." src="https://images.theconversation.com/files/520164/original/file-20230411-26-mi0289.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/520164/original/file-20230411-26-mi0289.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=390&fit=crop&dpr=1 600w, https://images.theconversation.com/files/520164/original/file-20230411-26-mi0289.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=390&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/520164/original/file-20230411-26-mi0289.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=390&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/520164/original/file-20230411-26-mi0289.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=490&fit=crop&dpr=1 754w, https://images.theconversation.com/files/520164/original/file-20230411-26-mi0289.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=490&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/520164/original/file-20230411-26-mi0289.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=490&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Unlike in most of the ocean, density layers in the Drake Passage slope downward, allowing phytoplankton to mix downward as well as sideways.</span>
<span class="attribution"><span class="source">Lilian Dove</span></span>
</figcaption>
</figure>
<p>With advances in <a href="https://doi.org/10.1029/2022GL102550">autonomous underwater robots</a> and computer modeling, we have been able to show how the flow of the Southern Ocean interacts with an underwater mountain in the Drake Passage. This underwater interaction <a href="https://doi.org/10.1029/2021GL097574">mixes up the ocean</a>, enhancing that coffeelike stirring process.</p>
<p>The stirring along the sloped density levels provides a pathway for water from the upper layer of the ocean to move into the depths. And phytoplankton at the surface ocean are carried along with this stirring, moving to depth much faster than they would by gravitational sinking alone.</p>
<p>In a less energetic region, these phytoplankton would die and respire their carbon back to the atmosphere or slowly sink. However, at the Drake Passage, phytoplankton can be swept to depth before this happens, meaning the carbon they’ve taken up from the atmosphere is sequestered in the deep ocean. Carbon dissolved and stored in the deep ocean may also vent out in these locations. </p>
<figure class="align-center ">
<img alt="Three people bundled up in winter gear work on a large seagoing drone." src="https://images.theconversation.com/files/520122/original/file-20230411-18-thnam3.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/520122/original/file-20230411-18-thnam3.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/520122/original/file-20230411-18-thnam3.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/520122/original/file-20230411-18-thnam3.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/520122/original/file-20230411-18-thnam3.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/520122/original/file-20230411-18-thnam3.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/520122/original/file-20230411-18-thnam3.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Author Lilian Dove, at right, works with oceanographer Isa Rosso and marine technician Richard Thompson to prepare an oceangoing autonomous vehicle to take measurements in the Southern Ocean.</span>
<span class="attribution"><span class="source">Linnah Neidel</span></span>
</figcaption>
</figure>
<p>Scientists have estimated that the deepest ocean waters directly interact with the atmosphere through only about <a href="https://doi.org/10.1038/308621a0">5% of the ocean’s surface area</a>. This is one of those special places.</p>
<p>Investigating the Drake Passage and other oceanographic windows allows science to home in on better understanding climate change and the workings of our blue planet.</p><img src="https://counter.theconversation.com/content/202428/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Lilian Dove receives funding from the National Science Foundation and Resnick Sustainability Institute.</span></em></p>
Working with underwater robots, scientists show how deep sea mountains and fast currents between Antarctica and South America play a crucial role in stabilizing the climate.
Lilian (Lily) Dove, Ph.D. Candidate in Oceanography, California Institute of Technology
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/194609
2022-11-16T20:12:55Z
2022-11-16T20:12:55Z
Behind the scenes: How COP27 reached a deal that supports better monitoring of oceans to curb climate crisis
<figure><img src="https://images.theconversation.com/files/495565/original/file-20221116-16-yjn9z8.png?ixlib=rb-1.1.0&rect=54%2C193%2C1946%2C1195&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Anya Waite (second from left) highlights the critical role of the ocean in regulating our climate, and the need to invest in observing oceans that store more than 90 per cent of all carbon, at COP27's Earth Information Day event.
</span> <span class="attribution"><a class="source" href="https://twitter.com/AlbertSFischer/status/1590331579947442176">(The Global Ocean Observing System)</a>, <span class="license">Author provided</span></span></figcaption></figure><iframe style="width: 100%; height: 100px; border: none; position: relative; z-index: 1;" allowtransparency="" allow="clipboard-read; clipboard-write" src="https://narrations.ad-auris.com/widget/the-conversation-canada/behind-the-scenes--how-cop27-reached-a-deal-that-supports-better-monitoring-of-oceans-to-curb-climate-crisis" width="100%" height="400"></iframe>
<p>It was 1 a.m. on Nov. 12, in a crowded meeting room on the outskirts of the <a href="https://www.cop27.eg/">COP27 climate conference</a> complex in Sharm El-Sheikh, Egypt. As co-chair of the <a href="https://www.goosocean.org/">Global Ocean Observing System</a> (GOOS), I joined representatives from nations around the world as they inched toward an agreement on how to observe the changing atmosphere, land and ocean more comprehensively to ensure the world can reach its climate targets.</p>
<p>Tabled by the representatives of the <a href="https://enb.iisd.org/negotiations/un-framework-convention-climate-change-unfccc#:%7E:text=">United Nations Framework Convention on Climate Change</a> (UNFCCC) and the World Meteorological Organization, the agreement would help improve and support the observation of the global climate system, including the oceans that control the climate.</p>
<p>The nations were prepared for these negotiations after COP27’s <a href="https://unfccc.int/event/earth-information-day-2022#:%7E:text=Earth%20Information%20Day%202022%20consisted,ongoing%20work%20under%20the%20UNFCCC.">Earth Information Day</a> event, which I moderated, but there was one hold up: The differences with a handful of nations for whom observation implied scrutiny on hard-to-manage emissions imposed by nations that caused most of the climate damage. It was frustratingly unclear whether the global goal would pass. The UNFCCC negotiators returned to the drawing board — working into the wee hours.</p>
<p>The following day, they emerged in weary triumph with an agreement on global observation. Soon after the agreement was completed, they turned their attention to the challenges of the next week’s COP agreements. Such unseen and often unglamorous efforts underpin the critical work to move nations to agreement at COP27.</p>
<h2>The carbon context</h2>
<p>The global ocean holds <a href="https://theconversation.com/why-a-net-zero-future-depends-on-the-oceans-ability-to-absorb-carbon-154453">50 times more carbon than the atmosphere and absorbs more carbon than all the rainforests on Earth</a>. To date, the <a href="https://doi.org/10.1126/science.aau5153">ocean has absorbed 40 per cent of fossil fuel emissions</a> through chemical processes collectively known as the ocean carbon pump.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/ew8TvXfei0Q?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">The global ocean holds 50 times more carbon than the atmosphere and absorbs more carbon than all the rainforests on Earth.</span></figcaption>
</figure>
<p>Despite having buffered human carbon emissions since the onset of global warming, the process by which oceans absorb carbon is changing at an uncertain rate. Coastal <a href="https://oceanservice.noaa.gov/ecosystems/coastal-blue-carbon/#:%7E:text=Salt%20marshes%2C%20mangroves%2C%20and%20seagrass,hundreds%20to%20thousands%20of%20years.">blue carbon ecosystems such as seagrasses and mangroves lock up critical carbon</a> stores in sediments and conserve a rich biodiversity. </p>
<p>But the largest carbon sink of all is on the high seas — the deep blue carbon embedded in the open ocean as plankton, salts and organic matter. Deep-blue carbon and the associated diverse ecosystems are challenging to observe due to difficulties in terms of access, expensive equipment and the fact that these exist beyond national jurisdictions.</p>
<p>This formal COP agreement provides a strong foundation for nations to act and for policymakers to heed the ocean observation community’s urgent appeal for investment in the internationally-linked observation systems that will resolve these problems. But these requests need to be focused and united — and the science community is anything but that.</p>
<h2>Bridging the science and policy gap</h2>
<p>Scientists, more often than not, have to focus on the technical minutiae of their work, even when attending such broad international meetings as COP27, to remain credible in their field. Intergovernmental work being done by groups like the UNFCCC’s <a href="https://unfccc.int/process/bodies/subsidiary-bodies/sbsta">Subsidiary Body for Scientific and Technological Advice</a> is, often, invisible to them. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1590353789336576001"}"></div></p>
<p>This week at the <a href="https://cop27oceanpavilion.vfairs.com/">Ocean Pavillion at COP27</a>, Nigel Topping, the UK’s COP26 lead, criticized “the narcissism of small differences” in the climate community, highlighting how researchers, NGOs and even governments, sometimes, fail to achieve consensus for climate action because of minor differences in their perspective. </p>
<p>At COP27, achieving <a href="https://www.archdaily.com/991870/during-cop27-the-necessity-to-achieve-net-zero-comes-into-sharp-focus">net-zero emissions is an urgent global necessity</a>. The time to act is now, and the private and public sectors, researchers and policymakers must work together toward this goal. Achieving net-zero within this timeframe will not be possible without a better understanding of <a href="https://science.nasa.gov/earth-science/oceanography/ocean-earth-system/climate-variability">crucial carbon-absorbing mechanisms</a>. </p>
<p>Ocean and climate forecasters continue to grapple with increasing uncertainty of climate models. But they can rely on strong frameworks from the intergovernmental institutions like the <a href="https://www.ipcc.ch/">Intergovernmental Panel on Climate Change (IPCC)</a>, which is building the bedrock of climate information through regular global assessments. This relies on the careful compilation of scientific knowledge and a remarkable international consensus process that informs governments and other stakeholders of the climate trajectory. </p>
<p>Internationally, several UN agencies have brought together the work of nations to support and inform global action based on the latest <a href="https://www.ipcc.ch/assessment-report/ar6/">IPCC analysis</a>. The World Meteorological Organization recently launched <a href="https://community.wmo.int/joint-study-group-wmo-greenhouse-gas-monitoring-sg-ghg">a study group</a> that has been working on the development of an international greenhouse gas monitoring system. </p>
<p>The <a href="https://www.goosocean.org/">Global Ocean Observing System</a> (GOOS), led by UNESCO’s Intergovernmental Oceanographic Commission, has proposed monitoring programs one of which — the <a href="https://www.goosocean.org/index.php?option=com_content&view=article&id=298&Itemid=433#:%7E:text=">Ocean Observing Co-Design</a> Program — has hightlighted the importance of ocean carbon observation for the global community.</p>
<h2>Emerging technologies</h2>
<p>Poorly co-ordinated efforts threaten our collective ability to set, track and meet climate targets. They can also hinder the development and scale-up of specific mitigation such as ocean-based <a href="https://www.climateworks.org/programs/carbon-dioxide-removal/oceans/">carbon dioxide removal (CDR)</a>. While using this technology is sometimes controversial, it’s critical if we want to follow what the IPPC says is now necessary.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1590426536196218880"}"></div></p>
<p>To be credible, CDR must be exceptionally well documented and carefully rolled out. It must also scale up quickly enough to impact the global climate. These competing demands are already causing tension within the community.</p>
<p>The <a href="https://www.imo.org/en/OurWork/Environment/Pages/London-Convention-Protocol.aspx">London Protocol</a> — one of the first global conventions adopted by the International Maritime Organization in 1975 to protect the marine environment from human activities — is framing ocean CDR technologies such as <a href="https://web.whoi.edu/ocb-fert/what-is-ocean-fertilization/#:%7E:text=Ocean%20fertilization%20is%20a%20form,down%20atmospheric%20CO2%20levels.">ocean fertilization</a> and <a href="https://oceanvisions.org/ocean-alkalinity-enhancement/">ocean alkalinity enhancement</a>.</p>
<h2>The need for an international climate observatory</h2>
<p>So how do we harness the UN climate frameworks into action? A <a href="https://www.ofi.ca/impact/policy/ocean-carbon/carbon-observatory">carbon or climate observatory</a> could emerge as a first mover for a global observation goal as a mandated observation system under the World Meteorological Organization. It would provide data and measurements to enhance global understanding of oceans’ capacity to continue to absorb carbon.</p>
<p>An international climate observatory would require leading nations to communicate, pool and co-ordinate their already substantial investments and expertise. Nations can draw on existing initiatives, such as the international telescopes or research from the International Space Station.</p>
<p>These commitments need to champion the multiple intergovernmental initiatives under the UNFCCC while maintaining a strong dialogue with the burgeoning private sector. </p>
<p>A new conversation is urgently needed to transform climate action — and the UNFCCC has initiated this conversation at COP27.</p><img src="https://counter.theconversation.com/content/194609/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Anya M. Waite is CEO and Scientific Director of the Ocean Frontier Institute. She volunteers as the Co-Chair of the Global Ocean Observing System, and serves on the WMO's Greenhouse Gas Study Group.</span></em></p>
COP27’s agreement on observing the oceans sets a strong foundation for policymakers to invest in internationally linked observation that will help countries better monitor these carbon sinks.
Anya M. Waite, CEO and Scientific Director, Ocean Frontier Institute; Professor and Associate VP Research, Dalhousie University
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/188340
2022-10-24T12:27:57Z
2022-10-24T12:27:57Z
Geoengineering the ocean to fight climate change raises serious environmental justice questions
<figure><img src="https://images.theconversation.com/files/489457/original/file-20221012-17-7piebk.jpg?ixlib=rb-1.1.0&rect=816%2C0%2C5465%2C3559&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">We could sink more carbon in the ocean to fight climate change, but should we?</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/fishermen-coming-back-to-the-beach-sland-of-mozambique-news-photo/617964338?phrase=ocean%20fishermen%20island">Eric Lafforgue/Art in All of Us/Corbis via Getty Images</a></span></figcaption></figure><p>Heat waves, droughts and extreme weather are <a href="https://www.ipcc.ch/report/sixth-assessment-report-working-group-ii/">endangering people and ecosystems</a> somewhere in the world almost every day. These extremes are exacerbated by climate change, driven primarily by increasing emissions of greenhouse gases that build up in the atmosphere and trap heat at the Earth’s surface. </p>
<p>With that in mind, researchers are <a href="https://www.bostonglobe.com/2022/10/20/business/hubspots-brian-halligan-gets-real-about-climate-change/">exploring ways</a> to pull carbon dioxide out of the atmosphere and lock it away – <a href="https://nap.nationalacademies.org/catalog/26278/a-research-strategy-for-ocean-based-carbon-dioxide-removal-and-sequestration">including using the ocean</a>. But while these techniques might work, they raise serious technical, social and ethical questions, many of which have no clear answers yet.</p>
<p>We study climate change <a href="https://scholar.google.com/citations?user=1nrd2msAAAAJ&hl=en">policy, sustainability</a> and <a href="https://scholar.google.com/citations?user=VADzLZAAAAAJ&hl=en">environmental justice</a>. Before people start experimenting with the health of the ocean, there are several key questions to consider.</p>
<h2>Ocean carbon dioxide removal 101</h2>
<p>The ocean covers about 70% of the planet, and it <a href="https://earthobservatory.nasa.gov/features/OceanCarbon">naturally takes up carbon dioxide</a>. In fact, <a href="https://www.nature.com/articles/s41467-020-18203-3#Sec2">about a quarter</a> of human-produced carbon dioxide ends up in the ocean.</p>
<p>Ocean carbon dioxide removal is any action designed to use the ocean to remove even more carbon dioxide from the atmosphere than it already does and store it. </p>
<p>It spans a wide range of techniques – from increasing the amount and vitality of carbon dioxide-absorbing <a href="https://doi.org/10.1002/wcc.529">mangrove forests</a> to using <a href="https://nap.nationalacademies.org/catalog/26278/a-research-strategy-for-ocean-based-carbon-dioxide-removal-and-sequestration">ocean fertilization</a> to stimulate the growth of phytoplankton that absorb carbon dioxide to building pipelines that pump <a href="https://digitalcommons.mainelaw.maine.edu/oclj/vol12/iss2/3/">liquid carbon dioxide into formations under the seabed</a>, where it can eventually solidify as carbonate rock.</p>
<figure class="align-center ">
<img alt="A cross-section of ocean showing different types of carbon capture, like ocean fertilization" src="https://images.theconversation.com/files/483878/original/file-20220912-10060-hpa6op.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/483878/original/file-20220912-10060-hpa6op.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=324&fit=crop&dpr=1 600w, https://images.theconversation.com/files/483878/original/file-20220912-10060-hpa6op.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=324&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/483878/original/file-20220912-10060-hpa6op.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=324&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/483878/original/file-20220912-10060-hpa6op.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=408&fit=crop&dpr=1 754w, https://images.theconversation.com/files/483878/original/file-20220912-10060-hpa6op.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=408&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/483878/original/file-20220912-10060-hpa6op.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=408&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Methods of ocean direct carbon removal.</span>
<span class="attribution"><a class="source" href="https://www.frontiersin.org/articles/10.3389/fclim.2021.664456/full">2021 Boettcher, Brent, Buck, Low, McLaren and Mengis, Frontiers, 2021</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>There are other forms of carbon dioxide removal – planting trees, for example. But they <a href="https://www.ipcc.ch/srccl/">require large amounts of land</a> that is needed for other essential uses, such as agriculture.</p>
<p>That’s why <a href="https://www.nationalacademies.org/news/2021/12/new-report-assesses-the-feasibility-cost-and-potential-impacts-of-ocean-based-carbon-dioxide-removal-approaches-recommends-u-s-research-program">interest in using the vast ocean is growing</a>.</p>
<h2>Would these methods store enough carbon?</h2>
<p>The first crucial question is whether ocean carbon dioxide removal techniques could significantly reduce atmospheric carbon dioxide and store it long term, beyond what the ocean already does. Greenhouse gas <a href="https://www.ipcc.ch/report/ar6/wg3/downloads/report/IPCC_AR6_WGIII_SPM.pdf">emissions are still increasing globally</a>, which means that ocean carbon dioxide removal would need to keep carbon dioxide out of the atmosphere for a long time, at least until greenhouse gas emissions have fallen.</p>
<p>Initial evidence suggests that some forms of ocean carbon dioxide removal, such as those that rely on short-lived biomass like kelp forests or phytoplankton, <a href="https://doi.org/10.1098/rsbl.2018.0781">may not keep captured carbon stored</a> for more than a few decades. That’s because most plant tissues are quickly recycled by decay or by sea creatures grazing on them.</p>
<p>In contrast, mechanisms that form minerals, like the interaction when carbon dioxide is pumped into basalt formations, or that alter the way seawater retains carbon dioxide, such as <a href="https://www.american.edu/sis/centers/carbon-removal/fact-sheet-ocean-alkalinization.cfm">increasing its alkalinity</a>, prevent carbon from escaping and are much more likely to keep it out of the atmosphere for hundreds or thousands of years.</p>
<h2>Ecological risks and benefits</h2>
<p>Another key question is what ecological benefits or risks accompany different ocean carbon dioxide removal approaches.</p>
<p>Research shows that some options, such as supporting mangrove forests, <a href="https://doi.org/10.1016/j.ecolecon.2020.106758">may promote biodiversity and benefit nearby human communities</a>.</p>
<p>However, other options could introduce novel risks. For example, growing and then sinking large amounts of kelp or algae <a href="https://doi.org/10.3389/fmars.2019.00107">could bring in invasive species</a>. Dissolving certain types of rock in the ocean could reduce ocean acidity. This would enhance the ocean’s ability to store carbon dioxide, but these rocks could also contain trace amounts of metals that could harm marine life, and these risks are <a href="https://doi.org/10.5194/bg-19-3683-2022">not well understood</a>.</p>
<figure class="align-center ">
<img alt="Satellite view of the coast showing swirls of phytoplankton" src="https://images.theconversation.com/files/483924/original/file-20220912-24-7r0v1n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/483924/original/file-20220912-24-7r0v1n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=300&fit=crop&dpr=1 600w, https://images.theconversation.com/files/483924/original/file-20220912-24-7r0v1n.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=300&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/483924/original/file-20220912-24-7r0v1n.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=300&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/483924/original/file-20220912-24-7r0v1n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=377&fit=crop&dpr=1 754w, https://images.theconversation.com/files/483924/original/file-20220912-24-7r0v1n.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=377&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/483924/original/file-20220912-24-7r0v1n.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=377&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Phytoplankton can grow explosively over a few days or weeks. Ocean fertilization is designed to supercharge that process to capture carbon dioxide, but it can have harmful affects for other marine life.</span>
<span class="attribution"><a class="source" href="https://earthobservatory.nasa.gov/features/Phytoplankton">Robert Simmon and Jesse Allen/NOAA/MODIS</a></span>
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</figure>
<p>Each process could also release some greenhouse gases, reducing its overall effectiveness.</p>
<h2>Interfering with nature is a social question</h2>
<p>The ocean affects everyone on the planet, but not everyone will have the same relationship to it or the same opportunities to have their opinions heard. </p>
<p>Much of the global population lives near the ocean, and some interventions <a href="https://doi.org/10.3389/fclim.2021.684063">might impinge on places that support jobs and communities</a>. For example, boosting algae growth could affect nearby wild fisheries or interfere with recreation. People and communities are going to evaluate these risks differently depending on how they are personally affected.</p>
<p>In addition, people’s trust in decision-makers often <a href="https://www.sciencedirect.com/science/article/pii/S0921800921000161">shapes their views of technologies</a>. Some ways of using the ocean to remove carbon, such as those close to the shore, could be governed locally. It’s less clear how decisions about the <a href="https://nap.nationalacademies.org/download/26278">high seas or deep ocean</a> would be made, since these areas are not under the jurisdiction of any one country or global governing body.</p>
<p>People’s perceptions will likely also be shaped by such factors as whether or not they see ocean carbon dioxide removal as <a href="https://doi.org/10.1016/j.gloenvcha.2013.06.002">interfering with nature or protecting it</a>. However, views of what is acceptable or not can change. As the impacts of climate change increase, <a href="https://doi.org/10.1111/cobi.13759">tolerance for some unconventional interventions seems to be growing</a>.</p>
<h2>It’s also an ethical question</h2>
<p>Ocean carbon dioxide removal also raises a variety of ethical questions that do not have straightforward answers.</p>
<p>For example, it forces people to consider the <a href="https://doi.org/10.5840/ijap201024221">relationship between humans and nonhumans</a>. Are humans obliged to intervene to reduce the impact on the climate, or ought we avoid ocean interventions? Do people have the right to purposefully intervene in the ocean or not? Are there specific obligations that humans ought to recognize when considering such options? </p>
<figure class="align-center ">
<img alt="People crouch down to plant mangroves." src="https://images.theconversation.com/files/489449/original/file-20221012-18-7t7a2q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/489449/original/file-20221012-18-7t7a2q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=420&fit=crop&dpr=1 600w, https://images.theconversation.com/files/489449/original/file-20221012-18-7t7a2q.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=420&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/489449/original/file-20221012-18-7t7a2q.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=420&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/489449/original/file-20221012-18-7t7a2q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=528&fit=crop&dpr=1 754w, https://images.theconversation.com/files/489449/original/file-20221012-18-7t7a2q.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=528&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/489449/original/file-20221012-18-7t7a2q.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=528&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Volunteers plant mangrove saplings in the Philippines.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/filipino-volunteers-plant-mangrove-saplings-during-the-news-photo/73318400?phrase=philippines%20planting%20mangroves&adppopup=true">Romeo Gacad/AFP via Getty Images</a></span>
</figcaption>
</figure>
<p>Other ethical questions revolve around who makes decisions about ocean carbon dioxide removal and the consequences. For example, <a href="https://doi.org/10.1111/1758-5899.12921">who should be involved in decision-making</a> about the ocean? Could relying on ocean carbon dioxide removal <a href="https://doi.org/10.1016/j.crm.2021.100324">reduce societies’ commitment</a> to reducing emissions through other means, such as by reducing consumption, increasing efficiency and transforming energy systems?</p>
<h2>Who pays?</h2>
<p>Finally, ocean carbon dioxide removal could be very expensive. </p>
<p>For example, mining and then adding rocks to reduce the ocean’s acidity has been <a href="https://doi.org/10.1088/1748-9326/aaa9c4">estimated to cost</a> between US$60 and $200 per ton of carbon dioxide removed. To put that into context, the world produced <a href="https://www.iea.org/news/global-co2-emissions-rebounded-to-their-highest-level-in-history-in-2021">more than 36 billion metric tons</a> of carbon dioxide from energy alone in 2021.</p>
<p>Even macroalgae cultivation could be in the <a href="https://doi.org/10.1146/annurev-marine-032122-113850">tens of billions of dollars</a> if done at the scale likely necessary to have an impact.</p>
<p>These methods are more expensive than many actions that reduce emissions right now. For instance, using solar panels to avoid carbon emissions can range from saving money to a cost of $50 per ton of carbon dioxide, while actions like reducing methane emissions are <a href="https://www.iea.org/data-and-statistics/charts/ghg-abatement-costs-for-selected-measures-of-the-sustainable-recovery-plan">even less expensive</a>. But the harm from continued climate change has been estimated to be in the <a href="https://www.nature.com/articles/s41558-019-0444-6">hundreds of billions annually</a> in the United States alone.</p>
<p>These costs raise more questions. For example, how much debt is fair for future generations to carry, and how should the costs be distributed globally to fix a global problem? </p>
<p>Ocean carbon dioxide removal <a href="https://nap.nationalacademies.org/download/26278">could become a useful method</a> for keeping global warming in check, but it should not be seen as a silver bullet, especially since there isn’t an effective global system for making decisions about the ocean.</p>
<p><em>Sarah Cooley, a former research scientist at Woods Hole Oceanographic Institution and director of climate science at the Ocean Conservancy, contributed to this article.</em></p><img src="https://counter.theconversation.com/content/188340/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Terre Satterfield receives funding from Pacific Institute for Climate Solutions
(F20-00333) to explore public attitudes toward OCDR</span></em></p><p class="fine-print"><em><span>Sonja Klinsky does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>
From planting mangroves to dumping minerals in the ocean, there are lots of ideas for ocean carbon dioxide removal – and even more questions.
Sonja Klinsky, Associate Professor and Senior Global Futures Scientist, Arizona State University
Terre Satterfield, Professor of Culture, Risk and the Environment, University of British Columbia
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/189260
2022-09-21T16:46:37Z
2022-09-21T16:46:37Z
Direct air capture: how advanced is technology to suck up carbon dioxide – and could it slow climate change?
<p>Humanity must remove up to 660 billion tonnes of carbon dioxide (CO₂) from the atmosphere by the end of the century to <a href="https://www.ipcc.ch/report/ar6/wg3/">limit global warming to 1.5°C</a>. That’s according to the most recent report by the Intergovernmental Panel on Climate Change (IPCC), which based its estimate on atmospheric CO₂ concentrations measured in 2020. </p>
<p>Removing this much CO₂ will involve more than simply planting lots of trees. Engineers and scientists are developing direct air capture technologies (DAC) which are supposed to pull vast quantities of CO₂ from the atmosphere while using <a href="https://royalsociety.org/topics-policy/projects/greenhouse-gas-removal/">very little land and water</a>. </p>
<p>A typical DAC unit uses large fans to push air through a liquid or solid material which can bind and remove CO₂, similar to how human lungs extract oxygen. The material is regenerated when heated, leaving concentrated CO₂. </p>
<p>The concentrated CO₂ can either be <a href="https://www.lse.ac.uk/granthaminstitute/explainers/what-is-carbon-capture-and-storage-and-what-role-can-it-play-in-tackling-climate-change/">permanently stored</a>, usually underground in depleted oil and gas reservoirs, or used to produce useful chemicals such as synthetic fuels. These fuels would re-release CO₂ when burned and so are technically carbon neutral. </p>
<p><a href="https://www.airbus.com/en/newsroom/news/2021-07-power-to-liquids-explained">Advocates of the technology</a> say this could reduce the need for fossil fuels and help industries that are difficult to decarbonise, such as aviation, reach net zero emissions. Others worry that DAC offers a distraction from the hard work of slashing carbon emissions. </p>
<p>These <a href="https://www.nature.com/articles/s41467-020-17203-7">critics</a> suggest that the high energy cost and materials used for DAC make it prohibitively expensive and so impractical on the tight timescale left to avert catastrophic climate change. The cost to remove a tonne of CO₂ with DAC can reach <a href="https://www.wri.org/insights/direct-air-capture-resource-considerations-and-costs-carbon-removal">US$600</a> (£522). </p>
<p>DAC technology is still in its <a href="https://pubs.rsc.org/en/content/articlelanding/2022/ee/d1ee03523a">infancy</a>. The International Energy Agency (IEA) <a href="https://www.iea.org/reports/direct-air-capture-2022">forecasts</a> that it will be removing 90 million tonnes a year in 2030, 620 million tonnes in 2040 and 980 million tonnes annually in 2050. </p>
<p>But as things stand, only <a href="https://www.iea.org/reports/direct-air-capture-2022">19 DAC projects</a> have come online since 2010, which collectively remove 0.008 million tonnes of CO₂ each year, equivalent to about seven seconds of global emissions from energy production <a href="https://www.iea.org/news/global-co2-emissions-rebounded-to-their-highest-level-in-history-in-2021">in 2021</a>. </p>
<figure class="align-center ">
<img alt="A tall metal structure with a mountain in the background." src="https://images.theconversation.com/files/484859/original/file-20220915-11733-nql57y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/484859/original/file-20220915-11733-nql57y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=423&fit=crop&dpr=1 600w, https://images.theconversation.com/files/484859/original/file-20220915-11733-nql57y.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=423&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/484859/original/file-20220915-11733-nql57y.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=423&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/484859/original/file-20220915-11733-nql57y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=531&fit=crop&dpr=1 754w, https://images.theconversation.com/files/484859/original/file-20220915-11733-nql57y.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=531&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/484859/original/file-20220915-11733-nql57y.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=531&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A DAC unit in Canada.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/squamish-bc-canada-august-21-2021-2028735989">David Buzzard/Shutterstock</a></span>
</figcaption>
</figure>
<p>DAC developers are working on projects that will remove about 1 million tonnes of CO₂ a year each in the mid-2020s. But they may struggle to improve energy efficiency and reduce costs fast enough to remove CO₂ at the necessary scale to meet the IEA’s forecasts for the 2030s. Here’s why. </p>
<h2>DAC deployment is gaining momentum</h2>
<p>The largest unit currently operating is <a href="https://climeworks.com/roadmap/orca">the Orca plant</a>, which was built by the company Climeworks in Iceland in 2021. As big as <a href="https://www.datacenterdynamics.com/en/news/climeworks-opens-the-worlds-largest-carbon-capture-facility-in-iceland/">two shipping containers</a>, Orca aims to capture and permanently store up to 4,000 tonnes of CO₂ annually by dissolving it in water and pumping it underground where it will react to form rock. </p>
<p>This is how much <a href="https://www.encon.be/en/calculation-co2-offsetting-trees">170,000 trees</a> on 340 hectares of land would absorb in a year. Unfortunately, cold weather in early 2022 <a href="https://www.independent.co.uk/climate-change/news/iceland-carbon-removal-orca-freeze-b2060663.html">froze the machinery</a> and <a href="https://carbonherald.com/worlds-largest-carbon-removal-plant-orca-freezes-over-in-iceland/">shut down the plant</a>.</p>
<p>Carbon Engineering, another DAC developer, is planning to deploy a unit in Texas in the US which it says will <a href="https://carbonengineering.com/news-updates/worlds-largest-direct-air-capture-and-sequestration-plant/">remove</a> and store up to 1 million tonnes of CO₂ a year once it <a href="https://www.iea.org/reports/ccus-around-the-world/dac-1">begins operating in 2024</a>. This venture includes a multi-million dollar investment from <a href="https://research.american.edu/carbonremoval/2020/12/11/united-airlines-is-investing-in-direct-air-capture-what-does-that-mean/">United Airlines</a> which is attempting to offset emissions from its flights as well as acquire synthetic fuels.</p>
<p>Carbon-neutral fuels might replace oil in aeroplanes and long-distance goods vehicles. But air-to-fuel technologies still need a more competitive business model than the fossil fuel industry. </p>
<p>This is unlikely to happen quickly, since the latter is so well-established and subsidised whereas the technology behind air-to-fuel is rudimentary and needs substantial investment to scale up.</p>
<h2>Costs are falling too slowly</h2>
<p>The IEA has estimated that removing up to 1 billion tonnes of CO₂ a year from the air with DAC plants in 2050 will consume up to 1,667 terawatt-hours of <a href="https://www.iea.org/reports/direct-air-capture-2022">energy</a> – equivalent to 1% of global consumption <a href="https://ourworldindata.org/energy-production-consumption">in 2019</a>. </p>
<p>Costs are expected to drop to between <a href="https://www.iea.org/reports/direct-air-capture-2022">US$125 and US$335</a> per tonne of CO₂ in the 2030s, with the prospect of reaching below <a href="https://www.bloomberg.com/news/features/2021-09-08/inside-the-world-s-largest-direct-carbon-capture-plant">US$100</a> by 2040. This will depend on DAC units being deployed and developers learning from these demonstration units, similar to how the cost of solar energy <a href="https://pubs.acs.org/doi/10.1021/acs.iecr.0c04839">fell over time</a>. </p>
<p>DAC could become financially viable in the 2030s if falling costs are met by the rising price of carbon in tax regimes. According to the <a href="https://blogs.imf.org/2022/07/21/more-countries-are-pricing-carbon-but-emissions-are-still-too-cheap/">International Monetary Fund</a>, the average price of CO₂ in the countries where carbon taxes or pricing mechanisms exist hit US$6 per tonne in 2022 and is set to increase to US$75 by 2030. </p>
<p>The EU Emission Trading System priced a tonne of CO₂ at <a href="https://blogs.imf.org/2022/07/21/more-countries-are-pricing-carbon-but-emissions-are-still-too-cheap/">US$90 a tonne in 2022</a>. The Inflation Reduction Act recently increased tax credits for companies removing and storing CO₂ in the US from <a href="https://theconversation.com/biden-signs-inflation-reduction-act-its-climate-promise-relies-heavily-on-carbon-capture-meaning-thousands-of-miles-of-pipeline-188591?notice=Article+has+been+updated">US$50 a tonne to US$180</a>. </p>
<p>But high carbon prices are far from the norm elsewhere. In China, the carbon price hovered between US$6 and US$9 per tonne in <a href="https://chinadialogue.net/en/climate/the-first-year-of-chinas-national-carbon-market-reviewed/">2021</a> and <a href="https://chinadialogue.net/en/climate/rebooting-chinas-carbon-credits-what-will-2022-bring/">2022</a>. </p>
<figure class="align-center ">
<img alt="Smoke rising from chimneys at a coal power station." src="https://images.theconversation.com/files/484861/original/file-20220915-7253-mp3yzp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/484861/original/file-20220915-7253-mp3yzp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/484861/original/file-20220915-7253-mp3yzp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/484861/original/file-20220915-7253-mp3yzp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/484861/original/file-20220915-7253-mp3yzp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/484861/original/file-20220915-7253-mp3yzp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/484861/original/file-20220915-7253-mp3yzp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Emitting carbon is still too cheap.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/smoking-chimney-coal-power-plant-793506691">Engel.ac/Shutterstock</a></span>
</figcaption>
</figure>
<p>DAC could also become viable if the CO₂ it removes is monetised. But this is risky. One application of DAC is enhanced oil recovery, which involves pumping concentrated CO₂ underground to extract more oil. </p>
<p><a href="https://www.wri.org/insights/co2-direct-air-capture-plant-will-help-extract-oil-texas-could-actually-be-good-climate">Estimates</a> suggest this method could emit 1.5 tonnes of CO₂ for each tonne removed. Although this strategy could reduce the net emissions of <a href="https://www.wri.org/insights/co2-direct-air-capture-plant-will-help-extract-oil-texas-could-actually-be-good-climate">conventional oil production</a>, it would still add carbon to the atmosphere. </p>
<p>Opportunity may arise in industries that need concentrated CO₂, like food manufacturers. The CO₂ price has surged from US$235 a tonne in <a href="https://www.reuters.com/world/uk/uk-pay-tens-millions-get-carbon-dioxide-pumping-again-2021-09-22/">September 2021</a> to upwards of <a href="https://www.theguardian.com/business/2022/sep/02/food-producer-warns-of-price-shock-as-carbon-dioxide-price-quadruples">US$1,200</a> recently. </p>
<p>This is because the majority of CO₂ in the UK is sourced from <a href="https://theconversation.com/how-soon-could-carbon-capture-technology-solve-industry-co-shortages-168310">the fertiliser industry</a>, where soaring natural gas prices have wreaked havoc. Although current global demand is limited to about <a href="https://iea.blob.core.windows.net/assets/50652405-26db-4c41-82dc-c23657893059/Putting_CO2_to_Use.pdf">250 million -300 million tonnes</a> a year, DAC could soon offer a more affordable and climate-neutral supply of CO₂.</p>
<p>New technologies may help make DAC cheaper. For example, a DAC start-up based in the UK called Mission Zero Technologies is aiming to use electricity instead of heat to regenerate the CO₂-absorbing material in DAC units. This, the company claims, would cut the energy requirements of DAC <a href="https://www.missionzero.tech/our-technology">fourfold</a>.</p>
<p>Unfortunately, cost estimates for DAC are highly uncertain. This is partly because they often come from the developers themselves rather than independent research. There is no commonly accepted approach for quantifying the actual costs of DAC, but my <a href="https://www.cranfield.ac.uk/people/dr-dawid-hanak-364515">research group</a> is working to verify the removal costs claimed by DAC developers and forecast by the IEA with a global network of <a href="https://www.cost.eu/actions/CA21127">academics and industrialists</a>. </p>
<h2>Will DAC slow global warming?</h2>
<p>The world needs to build about 30 DAC plants capable of removing more than 1 million tonnes of CO₂ a year every year <a href="https://www.iea.org/reports/direct-air-capture">between 2020 and 2050</a>. With only a few such plants expected to be operational by the mid-2020s, overcoming this shortfall will be hard, especially if costs remain high and breakthrough DAC technologies are not discovered and commercialised.</p>
<p>I believe that DAC is still an essential tool for slowing global warming. When the predicted cost reductions are achieved, DAC will unlock the path to large-scale CO₂ removal with a much smaller land and water footprint than other removal technologies in the <a href="https://www.iea.org/reports/direct-air-capture-2022">2030s and beyond</a>. </p>
<p>The role of DAC is not to compensate for rising emissions in the 2020s, but to close the emission gap and bring atmospheric CO₂ concentration down to limit global warming to 1.5°C during the decade and a bit approaching 2050. This is why governments and businesses should focus on ending their reliance on fossil fuels while supporting the research and development of DAC technology to drive its costs down. </p>
<hr>
<figure class="align-right ">
<img alt="Imagine weekly climate newsletter" src="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
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<p><strong><em>Don’t have time to read about climate change as much as you’d like?</em></strong>
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<hr><img src="https://counter.theconversation.com/content/189260/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Dawid Hanak's research group has received grants from UK research councils, the European Union and industrial partners.</span></em></p>
The cost of deploying a direct air capture unit must fall while the cost of emitting CO₂ rises.
Dawid Hanak, Associate Professor in Energy and Process Engineering, Cranfield University
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/188591
2022-08-12T06:09:14Z
2022-08-12T06:09:14Z
Biden signs Inflation Reduction Act: Its climate promise relies heavily on carbon capture, meaning thousands of miles of pipeline
<p>President Joe Biden signed a <a href="https://www.nytimes.com/live/2022/08/07/us/climate-tax-deal-vote">sweeping climate, energy and health care bill</a> on Aug. 16, 2022, that contains about US$370 billion to foster clean energy development and combat climate change, constituting the <a href="https://www.nytimes.com/live/2022/08/07/us/climate-tax-deal-vote">largest federal climate investment in history</a>. </p>
<p>Several studies project that its climate and energy provisions could enable the United States to reduce its greenhouse gas emissions <a href="https://rhg.com/research/inflation-reduction-act/">by around</a> <a href="https://repeatproject.org/docs/REPEAT_IRA_Prelminary_Report_2022-08-04.pdf">40% below 2005</a> levels by 2030. That would be a significant improvement over the <a href="https://repeatproject.org/docs/REPEAT_IRA_Prelminary_Report_2022-08-04.pdf">current projections of around 27%</a>, and it could put the U.S. within hailing range of its pledge under the Paris Agreement to reduce emissions <a href="https://unfccc.int/sites/default/files/NDC/2022-06/United%20States%20NDC%20April%2021%202021%20Final.pdf">by at least 50% by 2030</a>. </p>
<p>Notably, one linchpin of the new climate provisions is a set of incentives to substantially expand technologies that capture carbon dioxide and either store it underground or ship it for reuse.</p>
<p>So far, the uptake of carbon capture technologies has been slow. The costs are high, and these technologies can require miles of pipeline and vast amounts of underground storage, both of which can trigger local backlash. A recent study projected that the U.S. would have to construct <a href="https://www.reuters.com/business/environment/us-carbon-pipeline-proposals-trigger-backlash-over-potential-land-seizures-2022-02-07/">65,000 miles of carbon dioxide pipelines</a> to achieve net-zero emissions in 2050, a whopping 13 times the current capacity.</p>
<p>I’m the former founding co-director of the <a href="https://www.american.edu/sis/centers/carbon-removal/">Institute for Carbon Removal Law & Policy at American University</a>. While the new law, known as the <a href="https://s3.documentcloud.org/documents/22128080/inflation-reduction-act-of-2022.pdf">Inflation Reduction Act</a>, has many provisions designed to jump-start the carbon removal sector, it’s far from certain that the industry will be able to move quickly.</p>
<h2>One-sixth of all emissions cuts</h2>
<p>The Inflation Reduction Act includes two primary types of carbon capture.</p>
<p><a href="https://www.rff.org/publications/explainers/carbon-capture-and-storage-101/">Carbon capture and storage</a> entails capturing carbon dioxide generated during power generation and industrial processes, such as steel and concrete production, and transporting it for storage or use. The most common use to date has been for enhanced oil recovery – injecting the gas into oil and gas reservoirs <a href="https://www.vox.com/energy-and-environment/2019/10/2/20838646/climate-change-carbon-capture-enhanced-oil-recovery-eor">to extract more fossil fuels</a>.</p>
<p>It also seeks to drive deployment of <a href="https://www.wri.org/insights/direct-air-capture-resource-considerations-and-costs-carbon-removal">direct air capture technologies</a>, which can pull carbon dioxide out of the air. </p>
<p>A <a href="https://repeatproject.org/docs/REPEAT_IRA_Prelminary_Report_2022-08-04.pdf">Princeton University analysis</a> estimated that pertinent provisions of the legislation “would increase the use of carbon capture <a href="https://repeatproject.org/docs/REPEAT_IRA_Prelminary_Report_2022-08-04.pdf">13-fold by 2030 relative to current policy</a>,” with only a modest amount projected to come from carbon dioxide removal. This could translate into about one-sixth to one-fifth of its <a href="https://www.axios.com/newsletters/axios-generate-90a5dde8-7916-4c69-967c-fe1f9d1665f8.html?chunk=0&utm_term=emshare">projected carbon dioxide emissions reductions</a>.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/XxjNhLZCae0?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
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<p>Consistent with most of its other energy and climate provisions, the Inflation Reduction Act seeks to drive widespread deployment of carbon removal technologies through incentives. Most importantly, it substantially amends a provision of the U.S. tax code <a href="https://www.law.cornell.edu/uscode/text/26/45Q">referred to as 45Q</a>, which is designed to <a href="https://www.battelle.org/insights/white-papers/monetizing-carbon-emissions?creative=586800114917&keyword=45q%20tax%20credits&matchtype=p&source=google&medium=cpc&term=45q%20tax%20credits&creative=586800114917&campaign=Energy-Blogs-Carbon-Capture-45Q&gclid=Cj0KCQjwxb2XBhDBARIsAOjDZ34hZpFEvMpB1rsb83XMh0WnEf4m4AXCWUa18G_Hfh3GjF5ZZLGqyzUaAj9qEALw_wcB">drive corporate investments in carbon capture</a>.</p>
<p>Under its provisions, tax credits for capturing carbon dioxide at industrial facilities and power plants would increase from $50 per ton today to up to $85 per ton if the carbon is stored. If the carbon is used instead for oil drilling, the credit would go from $30 today to $60 per ton.</p>
<p>Credits for capturing carbon from air via direct air capture would also dramatically jump, from $50 to $180 per ton if the carbon dioxide is stored, and from $35 currently to $130 per ton if it is used.</p>
<p>The new law also moves back the deadline for starting construction of carbon capture facilities that qualify from 2026 to 2033, reduce the minimum capture requirements for obtaining credits, and permit direct payments for the full value of credits for the first five years of a project’s operation in lieu of tax credits.</p>
<h2>Missing pieces</h2>
<p>Currently there are <a href="https://www.globalccsinstitute.com/wp-content/uploads/2021/10/2021-Global-Status-of-CCS-Global-CCS-Institute-Oct-21.pdf">only a dozen carbon capture and storage facilities</a> in the U.S. and <a href="https://climatechampions.unfccc.int/companies-are-sucking-carbon-from-the-atmosphere-using-direct-air-capture-how-does-it-work/">a couple of direct air capture facilities</a> removing a small amount of carbon from the air.</p>
<p>There’s a reason the uptake of carbon capture, particularly direct air capture, has been slow. Direct air capture cost estimates vary from <a href="https://www.wri.org/insights/direct-air-capture-resource-considerations-and-costs-carbon-removal">$250 to $600 per ton</a>, according to one analysis, while experts have estimated that a price <a href="https://theconversation.com/these-machines-scrub-greenhouse-gases-from-the-air-an-inventor-of-direct-air-capture-technology-shows-how-it-works-172306">under $100 and closer to $50</a> could create a market.</p>
<p><a href="https://payneinstitute.mines.edu/wp-content/uploads/sites/149/2022/08/Payne-Institute-Commentary-CCUS-in-the-new-Inflation-Reduction-Act.pdf">Some experts believe</a> that the Inflation Reduction Act <a href="https://www.energyintel.com/00000182-85e1-d4e0-abc6-d5e130210000">sufficiently ratchets up 45Q credits</a> to start driving widespread construction of carbon capture and storage facilities in the power and industrial sectors. Others believe that the direct pay provision is “<a href="https://www.mwe.com/insights/carbon-capture-utilization-and-sequestration-tax-benefits-under-the-proposed-inflation-reduction-act/">the fundamental missing piece</a>” for carbon capture and storage because project developers and sponsors can avoid the often onerous and costly process of raising tax equity to qualify to use the credits.</p>
<p>There’s hope that the increase in credit values for direct air capture will help to foster “<a href="https://www.mwe.com/insights/carbon-capture-utilization-and-sequestration-tax-benefits-under-the-proposed-inflation-reduction-act/">synthetic economics</a>” for this nascent market, infusing sufficient capital to develop technologies at scales that are profitable. </p>
<p><iframe id="0QJIj" class="tc-infographic-datawrapper" src="https://datawrapper.dwcdn.net/0QJIj/6/" height="400px" width="100%" style="border: none" frameborder="0"></iframe></p>
<h2>Pipeline challenges ahead</h2>
<p>However, while the Inflation Reduction Act may appear helpful <a href="https://www.eenews.net/articles/how-the-climate-bill-could-strengthen-epa-regulations/">on a theoretical basis</a>, both carbon capture and storage and direct air capture could face some serious headwinds over the course of the next decade and beyond.</p>
<p>One major challenge could be resistance to the construction of pipelines to transport carbon dioxide to storage sites. In recent years, counties and private landowners in Iowa <a href="https://www.reuters.com/business/environment/us-carbon-pipeline-proposals-trigger-backlash-over-potential-land-seizures-2022-02-07/">have voiced opposition</a> to such projects, particularly the idea that the state might allow pipeline builders to seize private land for their projects.</p>
<p>Pipeline construction is also a point of contention for environmental groups, especially environmental justice organizations, and could lead to protracted litigation. This stems in part from a <a href="https://news.bloomberglaw.com/environment-and-energy/bidens-pipeline-rules-target-key-link-of-carbon-capture-buildout">carbon dioxide pipeline rupture</a> in Satartia, Mississippi, in 2020, which hospitalized 45 people.</p>
<p>If public opposition delays construction, projects could be pushed past the window for the incentives, leaving developers with expensive projects. While <a href="https://www.catf.us/wp-content/uploads/2018/11/CATF_Factsheet_CO2_EOR_LifeCycleAnalysis.pdf">some studies</a> argue that enhanced oil recovery results in a net reduction in carbon dioxide emissions, this may ultimately be a hard political sell for local communities.</p>
<p>The Inflation Reduction Act may ultimately brighten the prospects for carbon removal in America, but this is by no means assured, especially in the optimistic time frame of the next decade.</p>
<p><em>This article was updated Aug. 16, 2022, with President Biden signing the legislation.</em></p><img src="https://counter.theconversation.com/content/188591/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Wil Burns does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>
One estimate suggests at least a sixth of all emissions cuts expected from the Inflation Reduction Act would come from carbon capture.
Wil Burns, Professor of Research in Environmental Policy, American University School of International Service
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/187222
2022-07-20T04:08:39Z
2022-07-20T04:08:39Z
How not to solve the climate change problem
<figure><img src="https://images.theconversation.com/files/474727/original/file-20220718-76184-acu3kz.jpg?ixlib=rb-1.1.0&rect=23%2C149%2C794%2C477&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">This direct air capture plant in Iceland was designed to capture 4,000 metric tons of carbon dioxide per year.</span> <span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/AccentureHelpsClimeworksFilterMoreCO2fromtheAirandInspireOneBillionPeopletoBeClimatePositive/143f5d692743ac61c3543e984336f12c/photo">Climeworks 2021 via AP Photos</a></span></figcaption></figure><p>When politicians talk about reaching “net zero” emissions, they’re <a href="https://oxfamilibrary.openrepository.com/bitstream/handle/10546/621205/bp-net-zero-land-food-equity-030821-en.pdf">often counting on trees or technology</a> that can pull carbon dioxide out of the air. What they don’t mention is just how much these proposals or geoengineering would cost to allow the world to continue burning fossil fuels.</p>
<p>There are many proposals for removing carbon dioxide, but most make differences only at the edges, and carbon dioxide concentrations in the atmosphere have continued to increase relentlessly, even through the pandemic.</p>
<p>I’ve been <a href="https://scholar.google.com/citations?user=ovnjqjMAAAAJ&hl=en">working on climate change</a> for over four decades. Let’s take a minute to come to grips with some of the rhetoric around climate change and clear the air, so to speak.</p>
<h2>What’s causing climate change?</h2>
<p>As has been <a href="https://www.ipcc.ch/reports/">well established now for several decades</a>, the global climate is changing, and that change is <a href="https://www.ipcc.ch/report/sixth-assessment-report-working-group-i/">caused by human activities</a>.</p>
<p>When fossil fuels are burned for energy or used in transportation, they release carbon dioxide – a greenhouse gas that is the <a href="https://nca2018.globalchange.gov/">main cause of global heating</a>. Carbon dioxide stays in the atmosphere for centuries. As more carbon dioxide is added, its increasing concentration acts like a blanket, trapping energy near Earth’s surface that would otherwise escape into space. </p>
<p>When the amount of energy arriving from the Sun exceeds the amount of energy radiating back into space, the climate heats up. Some of that energy increases temperatures, and some increases evaporation and fuels storms and rains.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/474627/original/file-20220718-61161-ypcaki.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Illustration of energy in from the Sun vs energy out from Earth in greenhouse effect" src="https://images.theconversation.com/files/474627/original/file-20220718-61161-ypcaki.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/474627/original/file-20220718-61161-ypcaki.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=428&fit=crop&dpr=1 600w, https://images.theconversation.com/files/474627/original/file-20220718-61161-ypcaki.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=428&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/474627/original/file-20220718-61161-ypcaki.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=428&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/474627/original/file-20220718-61161-ypcaki.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=538&fit=crop&dpr=1 754w, https://images.theconversation.com/files/474627/original/file-20220718-61161-ypcaki.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=538&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/474627/original/file-20220718-61161-ypcaki.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=538&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">How the greenhouse effect works.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Earth%27s_greenhouse_effect_%28US_EPA,_2012%29.png">EPA</a></span>
</figcaption>
</figure>
<p>Because of these changes in atmospheric composition, the planet has warmed by <a href="https://earthobservatory.nasa.gov/world-of-change/global-temperatures">an estimated 1.1 degrees Celsius (2 F) since about 1880</a> and is well on the way to 1.5 C (2.7 F), which was highlighted as a goal not to be crossed if possible by <a href="https://unfccc.int/process-and-meetings/the-paris-agreement/the-paris-agreement">the Paris Agreement</a>. With the global heating and gradual increases in temperature have come increases in all kinds of <a href="https://nca2018.globalchange.gov/chapter/2/">weather and climate extremes</a>, from flooding to drought and heat waves, that cause huge damage, disruption and loss of life.</p>
<p>Studies shows that global carbon dioxide emissions will need to <a href="https://www.ipcc.ch/2018/10/08/summary-for-policymakers-of-ipcc-special-report-on-global-warming-of-1-5c-approved-by-governments/">reach net-zero carbon emissions by midcentury</a> to have a chance of limiting warming to even 2 C (3.6 F).</p>
<p>Currently, the <a href="https://www.bp.com/en/global/corporate/energy-economics/statistical-review-of-world-energy.html">main source of carbon dioxide</a> is China. But accumulated emissions matter most, and the United States leads, closely followed by Europe, China and others.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/474877/original/file-20220719-10084-w3wb1s.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Pie charts show CO2 emissions from fossil fuels in one year compared with cumulative for top emitting countries. China has the largest share in 2018; the U.S. has the largest share cumulatively" src="https://images.theconversation.com/files/474877/original/file-20220719-10084-w3wb1s.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/474877/original/file-20220719-10084-w3wb1s.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=332&fit=crop&dpr=1 600w, https://images.theconversation.com/files/474877/original/file-20220719-10084-w3wb1s.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=332&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/474877/original/file-20220719-10084-w3wb1s.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=332&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/474877/original/file-20220719-10084-w3wb1s.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=418&fit=crop&dpr=1 754w, https://images.theconversation.com/files/474877/original/file-20220719-10084-w3wb1s.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=418&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/474877/original/file-20220719-10084-w3wb1s.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=418&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Estimated shares of carbon dioxide emissions from fossil fuels in 2018 compared with cumulative emissions over time, based on data released by BP.</span>
<span class="attribution"><span class="source">Kevin Trenberth</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>What works to slow climate change?</h2>
<p>Modern society needs energy, but it does not have to be from fossil fuels.</p>
<p>Studies show that the <a href="https://theconversation.com/heres-how-to-meet-bidens-2030-climate-goals-and-dramatically-cut-greenhouse-gas-emissions-with-todays-technology-185263">most effective way to address the climate change</a> problem is to decarbonize the economies of the world’s nations. This means sharply increasing use of renewable energy – solar and wind <a href="https://www.lazard.com/perspective/levelized-cost-of-energy-levelized-cost-of-storage-and-levelized-cost-of-hydrogen/">cost less than new fossil fuel plants in much of the world</a> today – and the use of electric vehicles.</p>
<p>Unfortunately, this changeover to renewables has been slow, due in large part to the the huge and expensive infrastructure related to fossil fuels, along with the vast amount of dollars that can <a href="https://theconversation.com/rising-authoritarianism-and-worsening-climate-change-share-a-fossil-fueled-secret-181012">buy influence with politicians</a>. </p>
<h2>What doesn’t work?</h2>
<p>Instead of drastically cutting emissions, companies and politicians have grasped at alternatives. These include <a href="https://www.technologyreview.com/2022/07/01/1055324/the-us-government-is-developing-a-solar-geoengineering-research-plan/">geoengineering</a>; <a href="https://www.epw.senate.gov/public/index.cfm/carbon-capture">carbon capture and storage</a>, including “direct air capture”; and <a href="https://theconversation.com/why-corporate-climate-pledges-of-net-zero-emissions-should-trigger-a-healthy-dose-of-skepticism-156386">planting trees</a>. </p>
<p>Here’s the issue:</p>
<p>Geoengineering often means “solar radiation management,” which aims to emulate a volcano and add particulates to the stratosphere to reflect incoming solar radiation back to space and produce a cooling. It might partially work, but it could have <a href="https://doi.org/10.1073/pnas.1520795113">concerning side effects</a>.</p>
<p>The global warming problem is not sunshine, but rather that infrared radiation emitted from Earth is being trapped by greenhouse gases. Between the incoming solar and outgoing radiation is the whole weather and climate system and the hydrological cycle. Sudden changes in these particles or poor distribution <a href="https://doi.org/10.1073/pnas.1520795113">could have dramatic effects</a>. </p>
<figure class="align-center ">
<img alt="Illustration of solar rays bouncing off human-made aerosol layers and other sources" src="https://images.theconversation.com/files/474503/original/file-20220718-24-ry3cxy.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/474503/original/file-20220718-24-ry3cxy.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=409&fit=crop&dpr=1 600w, https://images.theconversation.com/files/474503/original/file-20220718-24-ry3cxy.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=409&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/474503/original/file-20220718-24-ry3cxy.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=409&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/474503/original/file-20220718-24-ry3cxy.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=514&fit=crop&dpr=1 754w, https://images.theconversation.com/files/474503/original/file-20220718-24-ry3cxy.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=514&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/474503/original/file-20220718-24-ry3cxy.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=514&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Some methods of solar radiation management that have been proposed.</span>
<span class="attribution"><a class="source" href="https://research.noaa.gov/article/ArtMID/587/ArticleID/2756/Simulated-geoengineering-evaluation-cooler-planet-but-with-side-effects">Chelsea Thompson, NOAA/CIRES</a></span>
</figcaption>
</figure>
<p>The last major volcanic eruption, of Mt. Pinatubo in 1991, sent enough sulfur dioxide and particulates into the stratosphere that it produced modest cooling, but it also <a href="https://doi.org/10.1029/2007GL030524">caused a loss of precipitation over land</a>. It cooled the land more than the ocean so that monsoon rains moved offshore, and longer term it slowed the water cycle. </p>
<p>Carbon capture and storage has been researched and tried for well over a decade but has <a href="https://cleanenergynews.ihsmarkit.com/research-analysis/wyoming-coal-plants-illustrate-cost-challenges-for-power-gener.html">sizable costs</a>. Only <a href="https://www.globalccsinstitute.com/wp-content/uploads/2021/10/2021-Global-Status-of-CCS-Report_Global_CCS_Institute.pdf">about a dozen</a> industrial plants in the U.S. currently capture their carbon emissions, and most of it is used to enhance drilling for oil.</p>
<p>Direct air capture – technology that can pull carbon dioxide out of the air – is being developed in several places. It uses a lot of energy, though, and while that could <a href="https://theconversation.com/offshore-wind-farms-could-help-capture-carbon-from-air-and-store-it-long-term-using-energy-that-would-otherwise-go-to-waste-173208">potentially be dealt with by using renewable energy</a>, it’s still energy intensive.</p>
<figure class="align-center ">
<img alt="A man holding onto a small tree speaks with reporters." src="https://images.theconversation.com/files/474986/original/file-20220719-6817-b56ls8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/474986/original/file-20220719-6817-b56ls8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=363&fit=crop&dpr=1 600w, https://images.theconversation.com/files/474986/original/file-20220719-6817-b56ls8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=363&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/474986/original/file-20220719-6817-b56ls8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=363&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/474986/original/file-20220719-6817-b56ls8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=457&fit=crop&dpr=1 754w, https://images.theconversation.com/files/474986/original/file-20220719-6817-b56ls8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=457&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/474986/original/file-20220719-6817-b56ls8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=457&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Boris Johnson, then mayor of London, plants a tree in 2008.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/mayor-of-london-boris-johnson-stands-beside-a-tree-that-he-news-photo/81069953">Peter Macdiarmid/Getty Images</a></span>
</figcaption>
</figure>
<p>Planting trees is often embraced as a solution for offsetting corporate greenhouse gas emissions. Trees and vegetation take up carbon dioxide though photosynthesis and produce wood and other plant material. It’s relatively cheap.</p>
<p>But trees aren’t permanent. Leaves, twigs and dead trees decay. Forests burn. Recent studies <a href="https://theconversation.com/trees-arent-a-climate-change-cure-all-2-new-studies-on-the-life-and-death-of-trees-in-a-warming-world-show-why-182944">show that the risks to trees</a> from stress, wildfires, drought and insects as temperatures rise will also be larger than expected.</p>
<h2>How much does all this cost?</h2>
<p>Scientists have been <a href="https://climate.nasa.gov/vital-signs/carbon-dioxide/">measuring carbon dioxide at Mauna Loa</a>, Hawaii, since 1958 and elsewhere. The average annual increase in carbon dioxide concentration has accelerated, from about 1 part per million by volume per year in the 1960s to 1.5 in the 1990s, to 2.5 in recent years since 2010.</p>
<p>This relentless increase, through the pandemic and in spite of efforts in many countries to cut emissions, shows how enormous the problem is.</p>
<figure class="align-center ">
<img alt="Chart showing increasing CO2 over time." src="https://images.theconversation.com/files/474729/original/file-20220718-76570-nxu8ou.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/474729/original/file-20220718-76570-nxu8ou.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=347&fit=crop&dpr=1 600w, https://images.theconversation.com/files/474729/original/file-20220718-76570-nxu8ou.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=347&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/474729/original/file-20220718-76570-nxu8ou.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=347&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/474729/original/file-20220718-76570-nxu8ou.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=436&fit=crop&dpr=1 754w, https://images.theconversation.com/files/474729/original/file-20220718-76570-nxu8ou.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=436&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/474729/original/file-20220718-76570-nxu8ou.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=436&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Carbon dioxide concentrations at Mauna Loa, Hawaii. The monthly mean, in red, rises and falls with the growing seasons. The black line is adjusted for the average seasonal cycle.</span>
<span class="attribution"><a class="source" href="https://gml.noaa.gov/ccgg/trends/">Kevin Trenberth, based on NOAA data</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Usually carbon removal is discussed in terms of mass, measured in megatons – millions of metric tons – of carbon dioxide per year, not in parts per million of volume. The mass of the atmosphere is about 5.5x10¹⁵ metric tons, but as carbon dioxide (molecular weight 42) is heavier than air (molecular weight about 29), 1 part per million by volume of carbon dioxide is <a href="https://doi.org/10.1175/JCLI-3299.1">about 7.8 billion metric tons</a>. </p>
<p>According to the World Resources Institute, the <a href="https://www.wri.org/research/carbonshot-federal-policy-options-carbon-removal-united-states">range of costs for direct air capture</a> vary between US$250 and $600 per metric ton of carbon dioxide removed today, depending on the technology, energy source and scale of deployment. Even if costs fell to $100 per metric ton, the cost of reducing the atmospheric concentrations of carbon dioxide by 1 part per million is around $780 billion. </p>
<p>Keep in mind that the carbon dioxide concentration in the atmosphere has risen from <a href="https://www.noaa.gov/news-release/carbon-dioxide-now-more-than-50-higher-than-pre-industrial-levels">about 280 parts per million</a> before the industrial era to around 420 today, and it is currently rising at <a href="https://gml.noaa.gov/ccgg/trends/">more than 2 parts per million per year</a>.</p>
<p>Tree restoration on one-third to two-thirds of suitable acres is estimated to be able to remove about 7.4 gigatons of carbon dioxide by 2050 without displacing agricultural land, by WRI’s calculations. That would be more than any other pathway. This might sound like a lot, but 7 gigatons of carbon dioxide is 7 billion metric tons, and so this is less than 1 part per million by volume. The cost is <a href="https://www.wri.org/insights/direct-air-capture-resource-considerations-and-costs-carbon-removal">estimated to be up to $50 per metric ton</a>. So even with trees, the cost to remove 1 part per million by volume could be as much as $390 billion.</p>
<p>Geoengineering <a href="https://doi.org/10.1073/pnas.1520795113">is also expensive</a>.</p>
<p>So for hundreds of billions of dollars, the best prospect with these strategies is a tiny dent of 1 part per million by volume in the carbon dioxide concentration.</p>
<p>This arithmetic highlights the tremendous need to cut emissions. There is no viable workaround.</p><img src="https://counter.theconversation.com/content/187222/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Kevin Trenberth does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>
A climate scientist looks at what works and some popular ideas that aren’t as cheap or effective as people hope.
Kevin Trenberth, Distinguished Scholar, NCAR; Affiliated Faculty, University of Auckland, Waipapa Taumata Rau
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/180663
2022-04-06T04:17:20Z
2022-04-06T04:17:20Z
On top of drastic emissions cuts, IPCC finds large-scale CO₂ removal from air will be “essential” to meeting targets
<figure><img src="https://images.theconversation.com/files/456513/original/file-20220406-18-eau0by.jpeg?ixlib=rb-1.1.0&rect=20%2C5%2C977%2C660&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption"></span> </figcaption></figure><p>Large-scale deployment of carbon dioxide removal (CDR) methods is now “unavoidable” if the world is to reach net-zero greenhouse gas emissions, according to this week’s <a href="https://www.ipcc.ch/report/sixth-assessment-report-working-group-3/">report</a> by the Intergovernmental Panel on Climate Change (IPCC). </p>
<p>The report, released on Monday, finds that in addition to rapid and deep reductions in greenhouse emissions, CO₂ removal is “an essential element of scenarios that limit warming to 1.5°C or likely below 2°C by 2100”.</p>
<p>CDR refers to a suite of activities that lower the concentration of CO₂ in the atmosphere. This is done by removing CO₂ molecules and storing the carbon in plants, trees, soil, geological reservoirs, ocean reservoirs or products derived from CO₂. </p>
<p>As the IPCC notes, each mechanism is complex, and has advantages and pitfalls. Much work is needed to ensure CDR projects are rolled out responsibly.</p>
<h2>How does CDR work?</h2>
<p>CDR is distinct from “carbon capture”, which involves catching CO₂ at the source, such as a coal-fired power plant or steel mill, before it reaches the atmosphere. </p>
<p>There are <a href="https://nap.nationalacademies.org/read/25259/chapter/1">several ways</a> to remove CO₂ from the air. They include:</p>
<ul>
<li><p><strong>terrestrial solutions</strong>, such as planting trees and adopting regenerative soil practices, such as low or no-till agriculture and cover cropping, which limit soil disturbances that can <a href="https://theconversation.com/farming-without-disturbing-soil-could-cut-agricultures-climate-impact-by-30-new-research-157153">oxidise soil carbon</a> and release CO₂.</p></li>
<li><p><strong>geochemical approaches</strong> that store CO₂ as a solid mineral carbonate in rocks. In a process known as “enhanced mineral weathering”, rocks such as limestone and olivine can be finely ground to increase their surface area and enhance a naturally occurring process whereby minerals rich in calcium and magnesium react with CO₂ to form a stable mineral carbonate.</p></li>
<li><p><strong>chemical solutions</strong> such as direct air capture that use <a href="https://theconversation.com/these-machines-scrub-greenhouse-gases-from-the-air-an-inventor-of-direct-air-capture-technology-shows-how-it-works-172306">engineered filters</a> to remove CO₂ molecules from air. The captured CO₂ can then be injected deep underground into saline aquifers and basaltic rock formations for durable sequestration.</p></li>
<li><p><strong><a href="https://nap.nationalacademies.org/read/26278/chapter/1">ocean-based</a> solutions</strong>, such as enhanced alkalinity. This involves directly adding alkaline materials to the environment, or electrochemically processing seawater. But these methods need to be further researched before being deployed.</p></li>
</ul>
<h2>Where is it being used right now?</h2>
<p>To date, US-based company Charm Industrial has <a href="https://charmindustrial.com/blog/largest-permanent-carbon-removal-delivery-of-all-time">delivered</a> 5,000 tonnes of CDR, which is the the largest volume thus far. This is equivalent to the emissions produced by about <a href="https://www.epa.gov/energy/greenhouse-gas-equivalencies-calculator#results">1,000 cars</a> in a year. </p>
<p>There are also several plans for larger-scale direct air capture facilities. In September, 2021, Climeworks <a href="https://climeworks.com/news/climeworks-launches-orca">opened</a> a facility in Iceland with a 4,000 tonne per annum capacity for CO₂ removal. And in the US, the Biden Administration has <a href="https://www.energy.gov/sites/default/files/2021-12/FECM%20Infrastructure%20Factsheet.pdf">allocated</a> US$3.5 billion to build four separate direct air capture hubs, each with the capacity to remove at least one million tonnes of CO₂ per year. </p>
<p>However, a previous IPCC <a href="https://www.ipcc.ch/sr15/download/#full">report</a> estimated that to limit global warming to 1.5°C, between 100 billion and one trillion tonnes of CO₂ must be removed from the atmosphere this century. So while these projects represent a massive scale-up, they are still a drop in the ocean compared with what is required.</p>
<p>In Australia, <a href="https://www.southerngreengas.com.au/">Southern Green Gas</a> and <a href="https://www.corporatecarbon.com.au/southern-green-gas-and-corporate-carbon-sign-mou-to-progress-dac">Corporate Carbon</a> are developing one of the country’s first direct air capture projects. This is being done in conjunction with University of Sydney researchers, ourselves included.</p>
<p>In this system, fans push atmospheric air over finely tuned filters made from molecular adsorbents, which can remove CO₂ molecules from the air. The captured CO₂ can then be injected deep underground, where it can remain for thousands of <a href="https://link.springer.com/article/10.1007/s12182-019-0340-8">years</a>.</p>
<h2>Opportunities</h2>
<p>It is important to stress CDR is not a replacement for emissions reductions. However, it can supplement these efforts. The IPCC has outlined three ways this might be done.</p>
<p>In the short term, CDR could help reduce net CO₂ emissions. This is crucial if we are to limit warming below critical temperature thresholds. </p>
<p>In the medium term, it could help balance out emissions from sectors such as agriculture, aviation, shipping and industrial manufacturing, where straightforward zero-emission alternatives don’t yet exist.</p>
<p>In the long term, CDR could potentially remove large amounts of historical emissions, stabilising atmospheric CO₂ and eventually bringing it back down to pre-industrial levels. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-earth-needs-multiple-methods-for-removing-co2-from-the-air-to-avert-worst-of-climate-change-121479">The Earth needs multiple methods for removing CO2 from the air to avert worst of climate change</a>
</strong>
</em>
</p>
<hr>
<p>The IPCC’s latest report has estimated the technological readiness levels, costs, scale-up potential, risk and impacts, co-benefits and trade-offs for 12 different forms of CDR. This provides an updated perspective on several forms of CDR that were lesser explored in previous reports. </p>
<p>It estimates each tonne of CO₂ retrieved through direct air capture will cost US$84–386, and that there is the feasible potential to remove between 5 billion and 40 billion tonnes annually.</p>
<h2>Concerns and challenges</h2>
<p>Each CDR method is complex and unique, and no solution is perfect. As deployment grows, a number of concerns must be addressed. </p>
<p>First, the IPCC notes scaling up CDR must not detract from efforts to dramatically reduce emissions. They <a href="https://report.ipcc.ch/ar6wg3/pdf/IPCC_AR6_WGIII_FinalDraft_FullReport.pdf">write that</a> “CDR cannot serve as a substitute for deep emissions reductions but can fulfil multiple complementary roles”.</p>
<p>If not done properly, CDR projects could potentially compete with agriculture for land or introduce non-native plants and trees. As the IPCC notes, care must be taken to ensure the technology does not negatively affect biodiversity, land-use or food security.</p>
<p>The IPCC also notes some CDR methods are energy-intensive, or could consume renewable energy needed to decarbonise other activities.</p>
<p>It expressed concern CDR might also exacerbate water scarcity and make Earth <a href="https://www.nature.com/articles/d41586-019-00122-z">reflect less sunlight</a>, such as in cases of large-scale reforestation.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/456500/original/file-20220406-18-7zqyor.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="An established forest is seen in the background, with smaller newly-planted trees in the front" src="https://images.theconversation.com/files/456500/original/file-20220406-18-7zqyor.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/456500/original/file-20220406-18-7zqyor.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/456500/original/file-20220406-18-7zqyor.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/456500/original/file-20220406-18-7zqyor.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/456500/original/file-20220406-18-7zqyor.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/456500/original/file-20220406-18-7zqyor.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/456500/original/file-20220406-18-7zqyor.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Forestry projects at high latitudes or in regions with high reflectivity can cover light-colored surfaces, and increase infrared radiation and warming.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/solar-panels-in-sahara-could-boost-renewable-energy-but-damage-the-global-climate-heres-why-153992">Solar panels in Sahara could boost renewable energy but damage the global climate – here's why</a>
</strong>
</em>
</p>
<hr>
<p>Given the portfolio of required solutions, each form of CDR might work best in different locations. So being thoughtful about placement can ensure crops and trees are planted where they won’t dramatically alter the Earth’s reflectivity, or use too much water. </p>
<p>Direct air capture systems can be placed in remote locations that have easy access to off-grid renewable energy, and where they won’t compete with agriculture or forests. </p>
<p>Finally, deploying long-duration CDR solutions can be quite expensive – far more so than short-duration solutions such as planting trees and altering soil. This has hampered CDR’s commercial viability thus far. </p>
<p>But costs are likely to decline, as they have for many other technologies including solar, wind and lithium-ion batteries. The trajectory at which CDR costs decline will vary between the technologies.</p>
<h2>Future efforts</h2>
<p>Looking forward, the IPCC recommends accelerated research, development and demonstration, and targeted incentives to increase the scale of CDR projects. It also emphasises the need for improved measurement, reporting and verification methods for carbon storage.</p>
<p>More work is needed to ensure CDR projects are deployed responsibly. CDR deployment must involve communities, policymakers, scientists and entrepreneurs to ensure it’s done in an environmentally, ethically and socially responsible way.</p><img src="https://counter.theconversation.com/content/180663/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Sam Wenger receives funding from the University of Sydney for his research on Direct Air Capture.</span></em></p><p class="fine-print"><em><span>Deanna D'Alessandro receives funding from Southern Green Gas Ltd. as part of a government-funded ARENA grant on Renewable Methane Generation with pipeline utility APA group and the University of Newcastle.</span></em></p>
While carbon dioxide removal from the air is not a replacement for emissions reductions, it can supplement these efforts. Experts are continually researching the best ways to do this.
Sam Wenger, PhD Student, University of Sydney
Deanna D'Alessandro, Professor & ARC Future Fellow, University of Sydney
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/174903
2022-01-21T13:34:42Z
2022-01-21T13:34:42Z
Net zero: UK government sued for weak strategy – so here’s what makes a good climate change plan
<figure><img src="https://images.theconversation.com/files/441968/original/file-20220121-17-k6y50j.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C5877%2C3909&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/bicycle-on-docking-station-london-694102603">Roserunn/Shutterstock</a></span></figcaption></figure><p><a href="https://ca1-eci.edcdn.com/reports/ECIU-Oxford_Taking_Stock.pdf">Two-thirds</a> of countries have now committed to reaching net zero greenhouse gas emissions at some point this century. During 2021, the share of large companies with net zero commitments jumped from one in five to one in three. </p>
<p>Sadly, few of these net zero targets were accompanied by measures necessary to achieve them. This discrepancy is increasingly the subject of <a href="https://www.lse.ac.uk/granthaminstitute/wp-content/uploads/2021/07/Global-trends-in-climate-change-litigation_2021-snapshot.pdf">legal challenges</a>. The governments of the Netherlands and Germany, as well as oil major Shell, are among defendants who have been ordered by courts to cut emissions faster. </p>
<p>Judges found that tepid climate strategies violated human rights laws by infringing on the rights of young people. Globally, the number of climate-related court cases has doubled since 2015. </p>
<p>The UK is the latest country whose government environmental groups have <a href="https://www.theguardian.com/environment/2022/jan/12/net-zero-climate-strategy-uk-government-sued">sued</a> for failing to take sufficient action on climate change. While the country’s net zero strategy deserves praise for some aspects – like setting a deadline to phase out new petrol and diesel cars by 2030 – even the government’s <a href="https://www.theccc.org.uk/publication/2021-progress-report-to-parliament/">climate change advisor</a> thinks it won’t be enough to meet statutory carbon targets.</p>
<p>So what does a good net zero strategy look like? In a new <a href="https://www.nature.com/articles/s41558-021-01245-w">perspective paper</a> we set out how to get net zero right. We argue that net zero strategies can be measured against three principles: the urgent pursuit of emission cuts, the cautious use of carbon offsets and carbon removal, and alignment with broader objectives for sustainable development.</p>
<h2>Urgency</h2>
<p>Because global temperature change is determined by cumulative emissions, the pace at which we reduce emissions is important. The longer we wait, the sooner the remaining carbon space in the atmosphere is used up.</p>
<p>Net zero strategies must contain measures to start cutting emissions immediately. These are often lacking or vague. The UK strategy, for example, proposes replacing gas boilers with heat pumps, but <a href="https://theconversation.com/heat-and-buildings-strategy-the-good-bad-and-ugly-of-the-uks-plan-to-replace-gas-boilers-170227">the support programme it offers</a> is available to only a small proportion of buildings and households. </p>
<figure class="align-center ">
<img alt="A pilot light inside a gas boiler." src="https://images.theconversation.com/files/441972/original/file-20220121-15-1ns5lky.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/441972/original/file-20220121-15-1ns5lky.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/441972/original/file-20220121-15-1ns5lky.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/441972/original/file-20220121-15-1ns5lky.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/441972/original/file-20220121-15-1ns5lky.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/441972/original/file-20220121-15-1ns5lky.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/441972/original/file-20220121-15-1ns5lky.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Gas boilers urgently need low-carbon replacements.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/water-heater-fire-close-560486227">Skimin0k/Shutterstock</a></span>
</figcaption>
</figure>
<p>Emissions cuts must also be comprehensive and include the most difficult sectors to decarbonise, such as heavy industry, aviation and agriculture. Tackling them will require consumers to make difficult choices, for example, on how much they travel and what they eat. Most net zero strategies shy away from spelling these out. </p>
<h2>Integrity</h2>
<p>The net zero strategies of many companies and governments rely heavily on carbon offsets. That is, rather than reducing their own emissions, they pay third parties to reduce theirs, for example, by funding renewable energy projects or planting trees.</p>
<p>This raises a number of problems. It is difficult to prove whether offsets <a href="https://theconversation.com/outdated-carbon-credits-from-old-wind-and-solar-farms-are-threatening-climate-change-efforts-151456">actually reduce emissions</a>. Many projects funded via offsets <a href="https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3950103">would have happened anyway</a>. The offset market needs much more rigorous regulation. </p>
<p>More importantly, net zero requires <em>all</em> emissions to come down. Offsets shouldn’t be used to allow pollution to continue unabated. They are a last resort.</p>
<p>If a strategy does include using offsets, those offsets should remove carbon from the atmosphere, rather than reduce emissions elsewhere. This is the meaning of net zero – a balance between emissions and removal. </p>
<p>Most options for removing carbon are biological, such as tree planting. Technological solutions, such as capturing carbon directly from the air and storing it underground, are still at the pilot stage, and there are concerns about their cost and ability to safely store CO₂. </p>
<figure class="align-center ">
<img alt="Volunteers carrying mangrove tree saplings in Malaysia." src="https://images.theconversation.com/files/441973/original/file-20220121-17-aqwttp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/441973/original/file-20220121-17-aqwttp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=388&fit=crop&dpr=1 600w, https://images.theconversation.com/files/441973/original/file-20220121-17-aqwttp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=388&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/441973/original/file-20220121-17-aqwttp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=388&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/441973/original/file-20220121-17-aqwttp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=487&fit=crop&dpr=1 754w, https://images.theconversation.com/files/441973/original/file-20220121-17-aqwttp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=487&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/441973/original/file-20220121-17-aqwttp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=487&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Tree planting isn’t a get out of jail free card.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/gelang-patahjohormalaysia-11april-2019-volunteers-join-1458851417">Farid Suhaimi/Shutterstock</a></span>
</figcaption>
</figure>
<p>Most modelled pathways for meeting the Paris Agreement’s goal of averting dangerous climate change involve scaling up carbon removal. The world needs more investment in these techniques, but also stronger legal frameworks to ensure their risks are managed properly, and an honest public debate to make sure people are on board with it. </p>
<h2>Sustainability</h2>
<p>Net zero strategies don’t work in isolation. They must be aligned with broader environmental, social and economic objectives. </p>
<p>Net zero strategies will fail unless they proactively manage the impact of decarbonisation policies on workers, communities and households. Thankfully, labour market interventions like re-skilling programmes can help workers transition into low-carbon employment and social welfare payments can shield households in poverty from energy price rises. Both must form an integral part of net zero strategies.</p>
<p>Climate action can have multiple additional benefits, for biodiversity, public health, and food security. But this is not guaranteed. Interventions can have unintended consequences. For example, commercial plantations of exotic tree species in naturally treeless habitats may claim to store carbon, but they could crowd out native species, rob local people of traditional livelihoods or succumb to pests and diseases. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/when-tree-planting-actually-damages-ecosystems-120786">When tree planting actually damages ecosystems</a>
</strong>
</em>
</p>
<hr>
<p>There are economic opportunities which net zero strategies should aim to capture. Low-carbon technologies like electric vehicles may unleash a virtuous cycle of innovation, investment and growth as information technology did two decades ago. More immediately, investment in, for example, <a href="https://theconversation.com/why-zero-carbon-homes-must-lead-the-green-recovery-from-covid-19-141149">home energy efficiency</a> and <a href="https://theconversation.com/five-ways-to-kickstart-a-green-recovery-141115">renewable energy</a> could help the economy recover from the pandemic in a sustainable way. Unfortunately, only <a href="https://academic.oup.com/oxrep/article/36/Supplement_1/S359/5832003?login=true">a fraction of economic recovery packages</a> offered by governments have been genuinely green. </p>
<p>The necessity of reaching net zero emissions is a scientific reality. The growth in net zero targets suggests that political and business leaders know this to be true. They are still struggling to make social, economic and political sense of net zero, as the emergence of court challenges shows. </p>
<p>But we are starting to understand <a href="https://www.nature.com/articles/s41558-021-01245-w">how to get net zero right</a>. If interpreted and governed well, net zero could be the best hope we have for climate action.</p>
<hr>
<figure class="align-right ">
<img alt="Imagine weekly climate newsletter" src="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
</figcaption>
</figure>
<p><strong><em>Don’t have time to read about climate change as much as you’d like?</em></strong>
<br><em><a href="https://theconversation.com/uk/newsletters/imagine-57?utm_source=TCUK&utm_medium=linkback&utm_campaign=Imagine&utm_content=DontHaveTimeTop">Get a weekly roundup in your inbox instead.</a> Every Wednesday, The Conversation’s environment editor writes Imagine, a short email that goes a little deeper into just one climate issue. <a href="https://theconversation.com/uk/newsletters/imagine-57?utm_source=TCUK&utm_medium=linkback&utm_campaign=Imagine&utm_content=DontHaveTimeBottom">Join the 10,000+ readers who’ve subscribed so far.</a></em></p>
<hr><img src="https://counter.theconversation.com/content/174903/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Sam Fankhauser receives funding from the University of Oxford's Strategic Research Fund for Oxford Net Zero and the UK Economic and Social Research Council (ESRC) for the Place-based Climate Action Network (PCAN). </span></em></p><p class="fine-print"><em><span>Kaya Axelsson receives funding from the University of Oxford's Strategic Research Fund for Oxford Net Zero and the World Business Council for Sustainable Development.</span></em></p>
Plan to cut emissions quickly, use offsets sparingly and set broader goals for improving society.
Sam Fankhauser, Professor of Climate Economics and Policy, University of Oxford
Kaya Axelsson, Net Zero Policy Engagement Fellow, University of Oxford
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/172306
2022-01-18T13:39:52Z
2022-01-18T13:39:52Z
These machines scrub greenhouse gases from the air – an inventor of direct air capture technology shows how it works
<figure><img src="https://images.theconversation.com/files/433063/original/file-20211122-23-3eqccw.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C1687%2C1077&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">One 'mechanical tree' is about 1,000 times faster at removing carbon dioxide from air than a natural tree. The first is to start operating in Arizona in 2022.</span> <span class="attribution"><a class="source" href="https://news.asu.edu/20210702-carbon-collect-mechanicaltree-selected-us-department-energy-award">Illustration via Arizona State University</a></span></figcaption></figure><p><em>Two centuries of burning fossil fuels has put more carbon dioxide, a powerful greenhouse gas, into the atmosphere than nature can remove. As that CO2 builds up, it <a href="https://theconversation.com/climate-change-is-relentless-seemingly-small-shifts-have-big-consequences-166139">traps excess heat</a> near Earth’s surface, causing global warming. There is so much CO2 in the atmosphere now that most scenarios show <a href="https://www.ipcc.ch/sr15/chapter/spm/">ending emissions alone won’t be enough</a> to stabilize the climate – humanity will also have to remove CO2 from the air.</em></p>
<p><em>The U.S. Department of Energy has a new <a href="https://www.energy.gov/articles/secretary-granholm-launches-carbon-negative-earthshots-remove-gigatons-carbon-pollution">goal</a> to scale up <a href="https://www.iea.org/reports/direct-air-capture">direct air capture</a>, a technology that uses chemical reactions to <a href="https://climeworks.com/roadmap/orca">capture CO2 from air</a>. While federal funding for carbon capture often draws criticism because some people see it as an excuse for fossil fuel use to continue, carbon removal in some form will likely <a href="https://www.ipcc.ch/sr15/chapter/spm/">still be necessary</a>, IPCC reports show. Technology to remove carbon mechanically is in development and operating at <a href="https://www.iea.org/reports/direct-air-capture">a very small scale</a>, in part because current methods are prohibitively expensive and energy intensive. But <a href="https://news.asu.edu/20210702-carbon-collect-mechanicaltree-selected-us-department-energy-award">new techniques</a> are being tested this year that could help lower the energy demand and cost.</em></p>
<p><em>We asked Arizona State University Professor <a href="https://sustainability-innovation.asu.edu/research/project/center-for-negative-carbon-emissions/">Klaus Lackner</a>, a pioneer in direct air capture and carbon storage, about the state of the technology and where it’s headed.</em></p>
<h2>What is direct carbon removal and why is it considered necessary?</h2>
<p>When I got interested in carbon management in the early 1990s, what drove me was the observation that carbon piles up in the environment. It takes nature <a href="https://doi.org/10.1038/climate.2008.122">thousands of years to remove that CO2</a>, and we’re on a <a href="https://climate.nasa.gov/vital-signs/carbon-dioxide/">trajectory toward much higher CO2</a> concentrations, well beyond anything humans have experienced.</p>
<p>Humanity can’t afford to have increasing amounts of excess carbon floating around in the environment, so we have to get it back out.</p>
<p>Not all emissions are from large sources, like <a href="https://ccsknowledge.com/pub/Publications/PAPER_GHGT15_SaskPowers_BD3_Journey_Achieving_Reliability_Mar2021.pdf">power plants or factories</a>, where we can capture CO2 as it comes out. So we need to deal with the other half of emissions – from cars, planes, taking a hot shower while your gas furnace is putting out CO2. That means pulling CO2 out of the air.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/XxjNhLZCae0?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">How direct air capture works.</span></figcaption>
</figure>
<p>Since CO2 mixes quickly in the air, it doesn’t matter where in the world the CO2 is removed – the removal has the same impact. So we can place direct air capture technology right where we plan to use or store the CO2. </p>
<p>The method of storage is also important. Storing CO2 for just 60 years or 100 years isn’t good enough. If 100 years from now all that carbon is back in the environment, all we did was take care of ourselves, and our grandkids have to figure it out again. In the meantime, the world’s energy consumption is growing at about <a href="https://yearbook.enerdata.net/total-energy/world-consumption-statistics.html">2% per year</a>. </p>
<h2>One of the complaints about direct air capture, in addition to the cost, is that it’s energy intensive. Can that energy use be reduced?</h2>
<p>Two large energy uses in direct air capture are running fans to draw in air and then heating to extract the CO2. There are ways to reduce energy demand for both.</p>
<p>For example, we stumbled into a material that attracts CO2 when it’s dry and releases it when wet. We realized we could expose that material to wind and it would load up with CO2. Then we could make it wet and it would <a href="https://pubs.rsc.org/en/content/articlelanding/2013/CP/C2CP43124F">release the CO2</a> in a way that requires far less energy than other systems. Adding heat created from renewable energy raises the CO2 pressure even higher, so we have a CO2 gas mixed with water vapor from which we can collect pure CO2.</p>
<figure class="align-center ">
<img alt="Two men stand beneath a large structure with fans" src="https://images.theconversation.com/files/433064/original/file-20211122-19-10oi9zt.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/433064/original/file-20211122-19-10oi9zt.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=375&fit=crop&dpr=1 600w, https://images.theconversation.com/files/433064/original/file-20211122-19-10oi9zt.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=375&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/433064/original/file-20211122-19-10oi9zt.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=375&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/433064/original/file-20211122-19-10oi9zt.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=472&fit=crop&dpr=1 754w, https://images.theconversation.com/files/433064/original/file-20211122-19-10oi9zt.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=472&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/433064/original/file-20211122-19-10oi9zt.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=472&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Climeworks, a Swiss company, has 15 plants removing carbon dioxide from the air.</span>
<span class="attribution"><a class="source" href="https://climeworks.com/purpose">Climeworks</a></span>
</figcaption>
</figure>
<p>We can save even more energy if the capture is passive – it isn’t necessary to have fans blowing the air around; the air moves on its own.</p>
<p>My lab is creating a method to do this, called <a href="https://news.asu.edu/20210702-carbon-collect-mechanicaltree-selected-us-department-energy-award">mechanical trees</a>. They’re tall vertical columns of discs coated with a chemical resin, about 5 feet in diameter, with the discs about 2 inches apart, like a stack of records. As the air blows through, the surfaces of the discs absorb CO2. After 20 minutes or so, the discs are full, and they sink into a barrel below. We send in water and steam to release the CO2 into a closed environment, and now we have a low-pressure mixture of water vapor and CO2. We can recover most of the heat that went into heating up the box, so the amount of energy needed for heating is quite small.</p>
<p>By using moisture, we can avoid about half the energy consumption and use renewable energy for the rest. This does require water and dry air, so it won’t be ideal everywhere, but there are also other methods. </p>
<h2>Can CO2 be safely stored long term, and is there enough of that type of storage?</h2>
<p>I started working on the concept of mineral sequestration in the 1990s, leading a group at Los Alamos. The world can actually put CO2 away permanently by taking advantage of the fact that it’s an acid and certain rocks are base. When CO2 reacts with minerals that are rich in calcium, <a href="https://www.nap.edu/read/25259/chapter/8#248">it forms solid carbonates</a>. By <a href="https://doi.org/10.1038/s41467-019-10003-8">mineralizing the CO2</a> like this, we <a href="https://doi.org/10.3133/sir20185079">can store</a> a nearly unlimited amount of carbon permanently.</p>
<p>For example, there’s lots of basalt – volcanic rock – in <a href="https://doi.org/10.1038/s41467-019-10003-8">Iceland that reacts with CO2</a> and turns it into solid carbonates within a few months. Iceland could sell certificates of carbon sequestration to the rest of the world because it puts CO2 away for the rest of the world.</p>
<p>There are also huge underground reservoirs from oil production in the Permian Basin in Texas. There are large saline aquifers. In the North Sea, a kilometer below the ocean floor, the energy company Equinor has been capturing CO2 from a gas processing plant and storing <a href="https://www.equinor.com/en/what-we-do/carbon-capture-and-storage.html">a million tons of CO2 a year</a> since 1996, avoiding Norway’s <a href="https://sequestration.mit.edu/tools/projects/sleipner.html">tax on CO2 releases</a>. The amount of underground storage where we can do mineral sequestration is far larger than we will ever need for CO2. The question is how much can be converted into proven reserve.</p>
<figure class="align-center ">
<img alt="Lackner is shown behind a device with a leafy plant being used for testing." src="https://images.theconversation.com/files/433075/original/file-20211122-13-1lb6dat.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/433075/original/file-20211122-13-1lb6dat.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=397&fit=crop&dpr=1 600w, https://images.theconversation.com/files/433075/original/file-20211122-13-1lb6dat.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=397&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/433075/original/file-20211122-13-1lb6dat.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=397&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/433075/original/file-20211122-13-1lb6dat.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=498&fit=crop&dpr=1 754w, https://images.theconversation.com/files/433075/original/file-20211122-13-1lb6dat.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=498&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/433075/original/file-20211122-13-1lb6dat.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=498&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Klaus Lackner tests direct air capture technologies in his lab.</span>
<span class="attribution"><a class="source" href="https://newsroom.asu.edu/expert/klaus-lackner">Arizona State University</a></span>
</figcaption>
</figure>
<p>We can also use direct air capture <a href="https://www.vox.com/energy-and-environment/2020/1/8/20841897/climate-change-carbon-capture-circular-economy-recycle">to close the carbon loop</a> – meaning CO2 is reused, captured and reused again to avoid producing more. Right now, people use carbon from fossil fuels to extract energy. You can convert CO2 to synthetic fuels – gasoline, diesel or kerosene – that have no new carbon in them by mixing the captured CO2 with <a href="https://www.greentechmedia.com/articles/read/green-hydrogen-explained">green hydrogen</a> created with renewable energy. That fuel can easily ship through existing pipelines and be stored for years, so you can produce heat and electricity in Boston on a winter night using energy that was collected as sunshine in West Texas last summer. A tankful of “synfuel” doesn’t cost much, and it’s more cost-effective than a battery.</p>
<h2>The Department of Energy set a new goal to slash the costs of carbon dioxide removal to US$100 per ton and quickly scale it up within a decade. What has to happen to make that a reality?</h2>
<p>DOE is scaring me because they make it sound like the technology is already ready. After neglecting the technology for 30 years, we can’t just say there are companies who know how to do it and all we have to do is push it along. We have to assume this is a nascent technology. </p>
<p>Climeworks is the largest company doing direct capture commercially, and it sells CO2 at <a href="https://www.bloomberg.com/news/features/2021-09-08/inside-the-world-s-largest-direct-carbon-capture-plant">around $500 to $1,000 per ton</a>. That’s too expensive. On the other hand, at $50 per ton, the world could do it. I think we can get there.</p>
<p>The U.S. consumes about 7 million tons of CO2 a year in <a href="https://www.iea.org/reports/putting-co2-to-use">merchant CO2</a> – think fizzy drinks, fire extinguishers, grain silos use it to control grain powder, which is an explosion hazard. The average price is $60-$150. So below $100 you have a market. </p>
<p>What you really need is a regulatory framework that says we demand CO2 is put away, and then the market will move from capturing kilotons of CO2 today to capturing gigatons of CO2.</p>
<h2>Where do you see this technology going in 10 years?</h2>
<p>I see a world that abandons fossil fuels, probably gradually, but has a mandate to capture and store all the CO2 long term.</p>
<p>Our recommendation is when carbon comes out of the ground, it should be matched with an equal removal. If you produce 1 ton of carbon associated with coal, oil or gas, you need to put 1 ton away. It doesn’t have to be the same ton, but there has to be a <a href="https://www.researchgate.net/publication/355713440_Project_overview_-2021_Strengthening_the_certification_process_of_carbon_sequestration_a_collaborative_effort_to_identify_gaps_and_offer_solutions">certificate of sequestration</a> that assures it has been put away, and it has to last more than 100 years. If all carbon is certified from the moment it comes out of the ground, it’s harder to cheat the system.</p>
<p>[<em>Get the best of The Conversation.</em> <a href="https://memberservices.theconversation.com/newsletters/?source=inline-weeklybest">Sign up for our weekly newsletter</a>.]</p>
<p>A big unknown is how hard industry and society will push to become carbon neutral. It’s encouraging to see companies like <a href="https://www.spglobal.com/platts/en/market-insights/latest-news/coal/012921-microsoft-buys-13-million-carbon-offsets-in-2021-portfolio">Microsoft</a> and <a href="https://stripe.com/newsroom/news/spring-21-carbon-removal-purchases">Stripe buying carbon credits</a> and certificates to remove CO2 and willing to pay fairly high prices.</p>
<p>New technology can take a decade or two to penetrate, but if the economic pull is there, things can go fast. The first commercial jet was available in 1951. By 1965 they were ubiquitous.</p><img src="https://counter.theconversation.com/content/172306/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Klaus Lackner is a Scientific Advisor to Carbon Collect and holds shares in the company, which is working with Arizona State University on developing an air capture device. He also advises Aircela, which is developing a household-scale system to convert ambient carbon dioxide into synthetic fuel. Lackner’s work in carbon management has over three decades been supported by research grants from private companies, foundations, universities and the U.S. Department of Energy.</span></em></p>
Klaus Lackner is finding new ways to cut the technology’s high costs and energy demand, and he’s about to launch the first ‘mechanical tree’.
Klaus Lackner, Professor of Engineering and Director of the Center for Negative Carbon Emissions, Arizona State University
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/171379
2021-11-16T22:30:50Z
2021-11-16T22:30:50Z
We can’t let markets decide the future of removing carbon from the atmosphere
<figure><img src="https://images.theconversation.com/files/431303/original/file-20211110-27-17ne8wq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Mike Pellinni / shutterstock</span></span></figcaption></figure><p>Net zero emission pledges by countries and companies are everywhere at the moment. Most of these pledges rely on massive amounts of carbon removal, yet details on how this will transpire remain largely absent. The COP26 agreement suggests that <a href="https://www.ft.com/content/f13bce2b-8a2b-4289-9281-9c6acf34f472">markets will play a central role</a>, but there are significant problems with this approach.</p>
<hr>
<iframe id="noa-web-audio-player" style="border: none" src="https://embed-player.newsoveraudio.com/v4?key=x84olp&id=https://theconversation.com/we-cant-let-markets-decide-the-future-of-removing-carbon-from-the-atmosphere-171379&bgColor=F5F5F5&color=D8352A&playColor=D8352A" width="100%" height="110px"></iframe>
<p><em>You can listen to more articles from The Conversation, narrated by Noa, <a href="https://theconversation.com/uk/topics/audio-narrated-99682">here</a>.</em></p>
<p>**</p>
<p>Carbon removal, also known as “negative emissions”, is the process of removing large amounts of CO₂ from the atmosphere. The most popular version involves planting trees, but there are other methods as well. These include combining bioenergy power plants with <a href="https://www.american.edu/sis/centers/carbon-removal/fact-sheet-bioenergy-with-carbon-capture-and-storage-beccs.cfm">carbon capture and storage</a>, or a technology called <a href="https://climeworks.com/">direct air capture</a>. Both of these currently only exist at tiny scales. </p>
<p>Many <a href="https://www.independent.co.uk/climate-change/news/greta-thunberg-climate-change-technologies-carbon-emissions-eu-a9380141.html">activists</a> and <a href="https://theconversation.com/climate-scientists-concept-of-net-zero-is-a-dangerous-trap-157368">scientists</a> consider large-scale carbon removal an unachievable pipedream and a <a href="https://www.oxfam.org/en/press-releases/net-zero-carbon-targets-are-dangerous-distractions-priority-cutting-emissions-says">major distraction</a> from near-term emission reductions. Others maintain that the window for achieving ambitious climate targets through emissions cuts alone <a href="https://jacobinmag.com/2018/07/carbon-removal-geoengineering-global-warming">has closed</a> and that it would be irresponsible or even <a href="https://nymag.com/intelligencer/2021/11/climate-change-reparations.html">unjust</a> to write off carbon removal completely.</p>
<p>Irrespective of where you stand in this debate, one thing is becoming increasingly clear: we cannot leave it to markets to decide whether and how to remove carbon from the atmosphere. Yet that is exactly what is happening. With everyone from <a href="https://oxfamilibrary.openrepository.com/bitstream/handle/10546/621205/bp-net-zero-land-food-equity-030821-en.pdf">European oil majors</a> to <a href="https://blogs.microsoft.com/blog/2020/01/16/microsoft-will-be-carbon-negative-by-2030/">big tech</a> eyeing up investments, the carbon removal agenda is rapidly becoming a function of market demand. </p>
<p>Already, we are seeing dramatic growth in forest-based carbon offsets, even though carbon stored in trees cannot <a href="https://theconversation.com/forests-cant-handle-all-the-net-zero-emissions-plans-companies-and-countries-expect-nature-to-offset-too-much-carbon-170336">compensate for continued fossil fuel emissions</a>. Meanwhile, corporations such as Microsoft are taking a more long-term approach by investing in direct air capture and a variety of <a href="https://www.nature.com/articles/d41586-021-02606-3">other new technologies</a>.</p>
<p>The new market mechanism that countries agreed to at COP26 promises to amplify this trend. Proponents hope it will bring about a <a href="https://www.ft.com/content/f13bce2b-8a2b-4289-9281-9c6acf34f472">veritable boom in carbon offsets</a>, where removals will likely play an increasing role. While it wouldn’t be the first time such high hopes end up deflated, many corporations clearly see the prospect of (cheap) removal credits as an appealing alternative to direct emission cuts. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/431305/original/file-20211110-21-jhgsvo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="An industrial building in a rocky valley" src="https://images.theconversation.com/files/431305/original/file-20211110-21-jhgsvo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/431305/original/file-20211110-21-jhgsvo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=423&fit=crop&dpr=1 600w, https://images.theconversation.com/files/431305/original/file-20211110-21-jhgsvo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=423&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/431305/original/file-20211110-21-jhgsvo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=423&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/431305/original/file-20211110-21-jhgsvo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=531&fit=crop&dpr=1 754w, https://images.theconversation.com/files/431305/original/file-20211110-21-jhgsvo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=531&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/431305/original/file-20211110-21-jhgsvo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=531&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">This direct air capture pilot plant in Canada removes one tonne of CO₂ per day.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/squamish-bc-canada-august-21-2021-2028735989">David Buzzard / shutterstock</a></span>
</figcaption>
</figure>
<p>In light of the corporate-friendly, market-based regime that has dominated climate politics for decades, it is hardly a surprise that carbon removal governance is <a href="https://www.carbonbrief.org/guest-post-learning-from-the-contentious-history-of-carbon-removal">moving in this direction</a>. But this approach closes down a conversation on some crucial questions: if large-scale carbon removal is to be used, then what and whose emissions should it compensate for, and how should those decisions be made?</p>
<h2>Whose emissions are “unavoidable”?</h2>
<p>In scientific models, one of the main features of carbon removal is its ability to “cancel out” continued greenhouse gas emissions, creating a climate-neutral balance between emissions and removals (hence the “net” in net zero). This allows some carbon-intensive activities to continue while still meeting climate goals.</p>
<p>This balancing act is necessary, <a href="https://pure.iiasa.ac.at/id/eprint/15340/">the argument goes</a>, because some emissions are particularly hard (or uneconomical) to eliminate, at least over the coming decades. Commonly mentioned examples are emissions from steel and cement production, agriculture, shipping, and aviation. While this might sound reasonable, there are no binding rules or criteria for deciding which emissions belong in this “hard-to-abate” or “residual” category. Despite efforts by NGOs and private actors to <a href="https://sciencebasedtargets.org/net-zero">define voluntary standards</a> it is, in effect, countries and companies themselves that currently get to define what emissions are hard-to-abate, hence how much removal they will need to rely on. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/431309/original/file-20211110-15-1nh9g87.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Large plane takes off at sunset" src="https://images.theconversation.com/files/431309/original/file-20211110-15-1nh9g87.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/431309/original/file-20211110-15-1nh9g87.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=403&fit=crop&dpr=1 600w, https://images.theconversation.com/files/431309/original/file-20211110-15-1nh9g87.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=403&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/431309/original/file-20211110-15-1nh9g87.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=403&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/431309/original/file-20211110-15-1nh9g87.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=506&fit=crop&dpr=1 754w, https://images.theconversation.com/files/431309/original/file-20211110-15-1nh9g87.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=506&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/431309/original/file-20211110-15-1nh9g87.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=506&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Electric planes are some way off, so aviation emissions are often considered hard-to-abate or ‘residual’.</span>
<span class="attribution"><span class="source">OlegRi / shutterstock</span></span>
</figcaption>
</figure>
<p>This obviously creates opportunities for greenwashing – and corporate net zero pledges already offer <a href="https://www.corporateaccountability.org/wp-content/uploads/2021/06/The-Big-Con_EN.pdf">countless</a> <a href="https://static1.squarespace.com/static/610ffde0dd5c39015edc6873/t/615316e8edeb561940f9653d/1632835305209/Meat_and_Dairy.pdf">examples</a> in this direction. But there is an additional concern: the demand from corporations seeking compensation for what they consider “necessary” emissions risks <a href="https://reliefweb.int/sites/reliefweb.int/files/resources/bp-net-zero-land-food-equity-030821-en.pdf">overshooting the realistic maximum amount of carbon removal</a>, and takes away opportunities from those with a more legitimate need for continued emissions in the near-term.</p>
<p>It is important to remember that <a href="https://www.nature.com/articles/s41558-017-0064-y">realistic carbon removal capacity</a> is limited. The more removals that countries and companies rely on, the more <a href="https://www.ipcc.ch/site/assets/uploads/sites/4/2020/02/SPM_Updated-Jan20.pdf">energy, land and resources</a> they will require. To minimise undesirable outcomes for people and ecosystems, it is crucial to limit the need for carbon removal.</p>
<h2>Allocating the residual emissions budget</h2>
<p>What is at stake, then, is the use and allocation of limited carbon removal capacity (you could call it a “residual emissions budget”). This begs the question: whose emissions are worth compensating? What kind of activities or groups of people have a legitimate claim on residual emissions? </p>
<p>To leave these decisions up to the market is to give up on the idea that carbon removal needs to proceed in a just and responsible way. It essentially means that those with the most purchasing power can appropriate the largest share of the residual emissions budget, to compensate for carbon-intensive activities of their own choosing.</p>
<p>A fairer allocation model would instead acknowledge that some countries have more capacity, and responsibility, for rapid emission reductions than others, and would allow developing countries to use most of the residual emissions budget. In such a model, it should still be wealthy countries and corporations that carry the burdens of carbon removal – they would just not be able to count this towards their own mitigation targets.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/a-global-carbon-removal-industry-is-coming-experts-explain-the-problems-it-must-overcome-169175">A global carbon removal industry is coming – experts explain the problems it must overcome</a>
</strong>
</em>
</p>
<hr>
<p>At present, the carbon removal market is a free-for-all, and allowing this to continue will likely lead to a race to the bottom and the proliferation of low-quality projects. The history of carbon markets is rife with examples of <a href="https://eia-global.org/press-releases/cdm-methodology-for-hfc-23-credits-should-be-retired">profiteering</a>, <a href="https://redd-monitor.org/2021/09/06/new-report-reveals-large-scale-deforestation-in-tumring-redd-project-in-cambodia/">land grabbing</a>, the <a href="https://www.oaklandinstitute.org/false-forest-uganda">violation of human rights</a> and projects that <a href="https://features.propublica.org/brazil-carbon-offsets/inconvenient-truth-carbon-credits-dont-work-deforestation-redd-acre-cambodia/">failed to deliver overall mitigation benefits</a>. These are clear warning signs for anyone professing the merits of a carbon removal market.</p>
<p>Whether to include carbon removal in mitigation efforts, how much, and how to allocate that limited allowance between different actors, are important political questions for democratic institutions to decide on, not markets or private capital. If governments are serious about justice and environmental integrity, then they urgently need to step up the regulation of carbon removal. At a minimum, governments need to agree on a constrained residual emissions budget and binding, climate justice-aligned criteria for the kinds of emissions that carbon removal can compensate for, and how that should be done.</p><img src="https://counter.theconversation.com/content/171379/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Wim Carton receives funding from FORMAS, the Swedish Research Council for Sustainable Development. </span></em></p><p class="fine-print"><em><span>Inge-Merete Hougaard receives funding from FORMAS and the Velux Foundation. She is affiliated with the Danish Climate Movement. </span></em></p><p class="fine-print"><em><span>Kirstine Lund Christiansen receives funding from the Independent Research Fund Denmark. She is affiliated with the Danish Climate Movement. </span></em></p>
Removing carbon from the atmosphere raises political questions that should be addressed by democratic institutions.
Wim Carton, Associate Professor of Political Ecology, Lund University
Inge-Merete Hougaard, Postdoctoral Fellow in Political Ecology, Lund University
Kirstine Lund Christiansen, PhD Fellow, Political Ecology, University of Copenhagen
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/167172
2021-10-26T19:02:49Z
2021-10-26T19:02:49Z
A quick guide to climate change jargon – what experts mean by mitigation, carbon neutral and 6 other key terms
<figure><img src="https://images.theconversation.com/files/447901/original/file-20220222-27-nvtrlb.png?ixlib=rb-1.1.0&rect=264%2C180%2C1234%2C799&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Climate jargon can feel overwhelming.</span> <span class="attribution"><span class="source">Illustration by Dennis Lan/USC</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>When scientists and policy writers talk about climate change, a lot of technical terms get tossed around: adaptation, carbon neutral, sustainable development. The language can feel overwhelming.</p>
<p>“It sounds like you’re talking over people,” one person said of the terminology during a <a href="https://link.springer.com/article/10.1007/s10584-021-03183-0">recent study</a> colleagues and I conducted through the <a href="https://publicexchange.usc.edu/">USC Dornsife Public Exchange</a>.</p>
<p>Authoritative reports about climate change can be difficult for nonscientists to understand. With the Intergovernmental Panel on Climate Change releasing new reports on <a href="https://www.ipcc.ch/report/sixth-assessment-report-working-group-3/">mitigation</a> and <a href="https://theconversation.com/transformational-change-is-coming-to-how-people-live-on-earth-un-climate-adaptation-report-warns-which-path-will-humanity-choose-177604">adaptation</a>, we thought it would be helpful to clarify some of the most common terms used to describe climate change.</p>
<p>We interviewed 20 people about common terms used by climate scientists and climate journalists. We then used their feedback to explain those terms in everyday language. With the help of the <a href="https://unfoundation.org/what-we-do/issues/climate-and-energy/climate-science/">United Nations Foundation</a>, we chose eight terms from reports written by the Intergovernmental Panel on Climate Change. </p>
<p>Here’s a guide that may help you to follow the news about climate change. The explanation of each term starts with the technical definition from the IPCC. The text that follows puts it into plain language.</p>
<h2>1. Mitigation</h2>
<p>IPCC definition: Mitigation (of climate change): a human intervention to reduce emissions or enhance the sinks of greenhouse gases.</p>
<p>Translation: Stopping climate change from getting worse.</p>
<p>When people talk about “mitigation” they often focus on fossil fuels – coal, oil and natural gas – used to make electricity and run cars, buses and planes. Fossil fuels produce greenhouse gases, including carbon dioxide. When these gases are released, they linger in the atmosphere. <a href="https://scied.ucar.edu/learning-zone/how-climate-works/greenhouse-effect">They then trap heat and warm the planet</a>.</p>
<p>Some ways to mitigate climate change include using solar and wind power instead of coal-fired power plants; making buildings, appliances and vehicles more energy efficient so they use less electricity and fuel; and designing cities so people have to drive less. Protecting forests and planting trees also help because trees <a href="https://sgp.fas.org/crs/misc/IF11404.pdf">absorb greenhouse gases from the atmosphere</a> and lock them away.</p>
<figure class="align-center ">
<img alt="Rows of solar panels curve along a hillside with mountains in the background." src="https://images.theconversation.com/files/428081/original/file-20211022-28-pz2o3j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/428081/original/file-20211022-28-pz2o3j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=382&fit=crop&dpr=1 600w, https://images.theconversation.com/files/428081/original/file-20211022-28-pz2o3j.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=382&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/428081/original/file-20211022-28-pz2o3j.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=382&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/428081/original/file-20211022-28-pz2o3j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=480&fit=crop&dpr=1 754w, https://images.theconversation.com/files/428081/original/file-20211022-28-pz2o3j.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=480&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/428081/original/file-20211022-28-pz2o3j.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=480&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Use of solar power as an alternative to fossil fuels is growing.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/view-shows-photovoltaic-solar-pannels-at-the-power-plant-in-news-photo/1137858606">Gerard Julien/AFP via Getty Images</a></span>
</figcaption>
</figure>
<h2>2. Adaptation</h2>
<p>IPCC definition: In human systems, the process of adjustment to actual or expected climate and its effects, in order to moderate harm or exploit beneficial opportunities. In natural systems, the process of adjustment to actual climate and its effects; human intervention may facilitate adjustment to expected climate and its effects.</p>
<p>Translation: Making changes to live with the impacts of climate change.</p>
<p><a href="https://royalsociety.org/topics-policy/projects/climate-change-evidence-causes/question-13/">Climate change is already happening.</a> Heat waves, wildfires and floods are getting worse. People will have to find ways to live with these threats. Los Angeles, for example, is <a href="https://www.cityplants.org/our-story/">planting trees</a> to help people stay cooler. Coastal cities like Miami may need <a href="https://theconversation.com/a-20-foot-sea-wall-wont-save-miami-how-living-structures-can-help-protect-the-coast-and-keep-the-paradise-vibe-165076">sea walls</a> to protect against floods. More “adaptation” actions will be needed as climate change gets worse.</p>
<h2>3. Carbon dioxide removal</h2>
<p>IPCC definition: Carbon dioxide removal methods refer to processes that <a href="https://theconversation.com/why-we-cant-reverse-climate-change-with-negative-emissions-technologies-103504">remove CO2</a> from the atmosphere by either increasing biological sinks of CO2 or using chemical processes to directly bind CO2. CDR is classified as a special type of mitigation. </p>
<p>Translation: Taking carbon dioxide out of the air.</p>
<p>The amount of carbon dioxide in the air has been increasing for many years. In 2019, there was <a href="https://www.metoffice.gov.uk/about-us/press-office/news/weather-and-climate/2021/2021-carbon-dioxide-forecast">50% more</a> more of it than in the late 1700s. <a href="https://theconversation.com/planting-trees-must-be-done-with-care-it-can-create-more-problems-than-it-addresses-128259">Planting trees</a> and <a href="https://theconversation.com/regenerative-agriculture-can-make-farmers-stewards-of-the-land-again-110570">restoring grasslands</a> can remove carbon dioxide from the air. There are also carbon dioxide removal technologies that <a href="https://theconversation.com/these-machines-scrub-greenhouse-gases-from-the-air-an-inventor-of-direct-air-capture-technology-shows-how-it-works-172306">store it underground</a> or <a href="https://theconversation.com/bendable-concrete-and-other-co2-infused-cement-mixes-could-dramatically-cut-global-emissions-152544">in concrete</a>, but these are new and not widely used.</p>
<figure class="align-center ">
<img alt="A machine with an intake and tubes behind two men talking." src="https://images.theconversation.com/files/427157/original/file-20211019-22-10mn5ec.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/427157/original/file-20211019-22-10mn5ec.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/427157/original/file-20211019-22-10mn5ec.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/427157/original/file-20211019-22-10mn5ec.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/427157/original/file-20211019-22-10mn5ec.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/427157/original/file-20211019-22-10mn5ec.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/427157/original/file-20211019-22-10mn5ec.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Washington Gov. Jay Inslee discusses equipment that can remove carbon dioxide from the air.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/govinslee/38394487681/in/photolist-2kTqfDL-2iAkN5S-21uMMxx-Dn1S5W-21uMLBK">Gov. Jay Inslee/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<h2>4. Carbon neutral</h2>
<p>IPCC definition: Carbon neutrality is achieved when anthropogenic CO2 emissions are balanced globally by anthropogenic carbon dioxide removals over a specified period. Carbon neutrality is also referred to as net-zero carbon dioxide emission.</p>
<p>Translation: Adding no net carbon dioxide into the air. This does not have to mean that you can’t add any carbon dioxide. It means that if you do add carbon dioxide into the air you take out the same amount.</p>
<p>The IPCC warns that the world needs to be <a href="https://www.ipcc.ch/2018/10/08/summary-for-policymakers-of-ipcc-special-report-on-global-warming-of-1-5c-approved-by-governments/">carbon neutral by 2050</a> to avoid a serious climate crisis. This means using both “mitigation” to reduce the amount of carbon dioxide added to the air and “carbon dioxide removal” to take carbon dioxide out of the air.</p>
<h2>5. Tipping point</h2>
<p>IPCC definition: A level of change in system properties beyond which a system reorganizes, often abruptly, and does not return to the initial state even if the drivers of the change are abated. For the climate system, it refers to a critical threshold when global or regional climate changes from one stable state to another stable state.</p>
<p>Translation: When it is too late to stop effects of climate change.</p>
<p>One of the most talked-about tipping points involves the collapse of the West Antarctic ice sheet. Some research suggests it <a href="https://www.science.org/doi/10.1126/sciadv.abd7254">may have already started happening</a>. West Antarctica alone holds enough ice to raise sea levels worldwide by <a href="https://www.carbonbrief.org/guest-post-how-close-is-the-west-antarctic-ice-sheet-to-a-tipping-point">about 11 feet</a> (3.3 meters). If all glaciers and ice caps melt, sea levels will end up rising about <a href="https://www.usgs.gov/faqs/how-would-sea-level-change-if-all-glaciers-melted?qt-news_science_products=0#qt-news_science_products">230 feet</a> (70 meters). </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/sXOi1MR0-Yw?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Why the West Antarctic ice sheet may have passed a tipping point.</span></figcaption>
</figure>
<h2>6. Unprecedented transition</h2>
<p>IPCC definition for “transition”: The process of changing from one state or condition to another in a given period of time. Transition can be in individuals, firms, cities, regions and nations and can be based on incremental or transformative change.</p>
<p>Translation: Making big changes together to stop climate change – in a way that has not been seen before.</p>
<p>In 2015, <a href="https://unfccc.int/process-and-meetings/the-paris-agreement/the-paris-agreement">countries around the world agreed</a> to try to keep the planet from warming more than 1.5 degrees Celsius (2.7 F). Among the <a href="https://ar5-syr.ipcc.ch/ipcc/sites/default/files/AR5_SYR_Figure_1.7.png">biggest sources of global warming</a> are coal-fired power plants. Quickly shifting the world to renewable energy, such as wind and solar power, would be an unprecedented transition. Without big changes, climate change could make the world unlivable.</p>
<h2>7. Sustainable development</h2>
<p>IPCC definition: Development that meets the needs of the present without compromising the ability of future generations to meet their own needs and balances social, economic and environmental concerns.</p>
<p>Translation: Living in a way that is good for people alive today and for people in the future.</p>
<p>The United Nations has shared <a href="https://sdgs.un.org/goals">“sustainable development goals.”</a> These goals aim to help countries grow in ways that are healthy for both people and the environment. Producing more carbon dioxide than the planet can manage is an example of unsustainable development that’s <a href="https://www.ipcc.ch/report/ar6/wg1/">causing climate change</a>. </p>
<figure class="align-center ">
<img alt="A chart of CO2 concentrations based on ice core reconstructions and modern observations" src="https://images.theconversation.com/files/427158/original/file-20211019-18-fkodu7.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/427158/original/file-20211019-18-fkodu7.gif?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/427158/original/file-20211019-18-fkodu7.gif?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/427158/original/file-20211019-18-fkodu7.gif?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/427158/original/file-20211019-18-fkodu7.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/427158/original/file-20211019-18-fkodu7.gif?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/427158/original/file-20211019-18-fkodu7.gif?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Levels of carbon dioxide in the air have risen quickly over the past 70 years.</span>
<span class="attribution"><a class="source" href="https://climate.nasa.gov/vital-signs/carbon-dioxide/">NOAA</a></span>
</figcaption>
</figure>
<h2>8. Abrupt change</h2>
<p>IPCC definition: Abrupt climate change refers to a large-scale change in the climate system that takes place over a few decades or less, persists (or is anticipated to persist) for at least a few decades and causes substantial disruptions in human and natural systems.</p>
<p>Translation: A change in climate that happens much faster than it normally would.</p>
<p>[<em>Over 140,000 readers rely on The Conversation’s newsletters to understand the world.</em> <a href="https://memberservices.theconversation.com/newsletters/?source=inline-140ksignup">Sign up today</a>.]</p>
<p>Our world is changing quickly as a result of climate change. Wildfires are raging in parts of the Western U.S. <a href="https://www.pnas.org/content/118/22/e2009717118">that were once too wet to burn</a>. Coral reefs are <a href="https://www.iucn.org/resources/issues-briefs/coral-reefs-and-climate-change">dying as the ocean is getting warmer</a>. These changes would not have happened so quickly – or at all – were it not for climate change. </p>
<p><em>Lance Ignon, a former communications adviser for the IPCC and now senior associate dean for strategic initiatives and communication at USC Dornsife and a co-author of the paper with <a href="https://priceschool.usc.edu/people/wandi-bruine-de-bruin/">Wändi Bruine de Bruin</a>, <a href="https://cesr.usc.edu/people/staff/lilarabi">Lila Rabinovich</a>, <a href="https://dornsife.usc.edu/kate-weber/">Kate Weber</a> <a href="https://publicexchange.usc.edu/about-us/">Marianna Babboni</a> and <a href="https://unfoundation.org/author/monica-dean/">Monica Dean</a>, contributed to this article.</em> </p>
<p><em>This article was updated Feb. 28, 2022, with the new IPCC report.</em></p><img src="https://counter.theconversation.com/content/167172/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Wändi Bruine de Bruin has received support from the University of Southern California Dornsife College Public Exchange and the Center for Climate and Energy Decision Making (CEDM) through a cooperative agreement between the National Science Foundation and Carnegie Mellon University. This project is a collaboration between the University of Southern California and the United Nations Foundation.</span></em></p>
The language around climate change can feel overwhelming. A psychology and public policy expert breaks it down in plain English.
Wändi Bruine de Bruin, Professor of Public Policy, Psychology and Behavioral Science, USC Sol Price School of Public Policy, USC Dornsife College of Letters, Arts and Sciences
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/167527
2021-09-09T04:57:15Z
2021-09-09T04:57:15Z
A promising new dawn is ours for the taking – so let’s stop counting the coal Australia must leave in the ground
<figure><img src="https://images.theconversation.com/files/420151/original/file-20210909-27-z41u74.jpg?ixlib=rb-1.1.0&rect=0%2C549%2C5979%2C3458&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>A <a href="https://doi.org/10.1038/s41586-021-03821-8">study out today</a> says the vast majority of Earth’s coal, including 95% of Australia’s, cannot be burned if global warming is to be limited to 1.5°C this century. The findings are undoubtedly true. But examining how much fossil fuel the world can still use is not the question we should be asking.</p>
<p>Instead, the most useful questions are: how do we advance Australia’s economic future outside high-emissions industries? And how can we seize the opportunities presented by the declines of coal, and then gas, rather than watching the economy go underwater as we try to stem an unstoppable tide?</p>
<p>The world is moving away fossil fuels, and there’s nothing Australia can do about it. Racing to dig up and sell whatever fossil fuels we can before the timer stops is not a future-proof strategy. We need to prepare for the change and diversify the economy.</p>
<p>How much coal must remain in the ground is beside the point. Instead, we should grasp this moment – turning it into a positive step for the world community and future generations.</p>
<figure class="align-center ">
<img alt="Boy with painted hands" src="https://images.theconversation.com/files/420155/original/file-20210909-18-1t2hl5t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/420155/original/file-20210909-18-1t2hl5t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/420155/original/file-20210909-18-1t2hl5t.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/420155/original/file-20210909-18-1t2hl5t.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/420155/original/file-20210909-18-1t2hl5t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/420155/original/file-20210909-18-1t2hl5t.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/420155/original/file-20210909-18-1t2hl5t.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The key question is, how do we turn this moment into an opportunity?</span>
<span class="attribution"><span class="source">Neil Hall/EPA</span></span>
</figcaption>
</figure>
<h2>The numbers game</h2>
<p>The new <a href="https://doi.org/10.1038/s41586-021-03821-8%20link">study</a> by researchers at University College London examines how much fossil fuel can still be burned if we hope to keep the global average temperature rises to within 1.5°C – the ambitious end of the Paris Agreement goals. It compares this “budget” with the known stores of coal, oil and gas in various parts of the world. </p>
<p>The study finds the vast majority of remaining fossil fuels must remain in the ground – specifically 89% of coal, 59% of gas and 58% of oil. For Australia, that equates to 95% of our coal reserves and 35% of our gas. </p>
<p>The research is a follow-up to a <a href="https://www.nature.com/articles/nature14016">well-known 2015 study</a> based on the 2°C warming scenario. Similar findings have also been made in other research.</p>
<p>While it’s long been clear that much of Earth’s fossil fuel deposits must stay in the ground, there are uncertainties around the numbers. These come from varying assumptions about:</p>
<ul>
<li><p>the exact size of the remaining global <a href="https://carbontracker.org/carbon-budgets-explained/">carbon budget</a> for any particular temperature increase</p></li>
<li><p>how the carbon budget might be distributed between coal, oil and gas (which depends on technology choices and costs)</p></li>
<li><p>the extent of carbon capture and <a href="https://www.climatecouncil.org.au/resources/what-is-carbon-capture-and-storage/">storage</a> (or carbon <a href="https://www.iea.org/fuels-and-technologies/carbon-capture-utilisation-and-storage">use</a>) and removal of carbon dioxide (CO₂) from the atmosphere </p></li>
<li><p>how much fossil fuel would be available for extraction. </p></li>
</ul>
<p>The study released overnight offers results only from a single model and data set. The results remind us how little time remains to keep using fossil fuels, but we should not focus unduly on the headline numbers the study produced. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/yes-it-is-entirely-possible-for-australia-to-phase-out-thermal-coal-within-a-decade-167366">Yes, it is entirely possible for Australia to phase out thermal coal within a decade</a>
</strong>
</em>
</p>
<hr>
<figure class="align-center ">
<img alt="Vehicle carries coal at mine" src="https://images.theconversation.com/files/420154/original/file-20210909-18-suz1ql.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/420154/original/file-20210909-18-suz1ql.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=403&fit=crop&dpr=1 600w, https://images.theconversation.com/files/420154/original/file-20210909-18-suz1ql.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=403&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/420154/original/file-20210909-18-suz1ql.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=403&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/420154/original/file-20210909-18-suz1ql.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=507&fit=crop&dpr=1 754w, https://images.theconversation.com/files/420154/original/file-20210909-18-suz1ql.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=507&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/420154/original/file-20210909-18-suz1ql.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=507&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">It’s long been clear much of Earth’s coal deposits should stay in the ground.</span>
<span class="attribution"><span class="source">Rob Griffith/AP</span></span>
</figcaption>
</figure>
<h2>3 lenses on the end of the fossil fuel age</h2>
<p>Just as the Stone Age didn’t end for a lack of stones, the fossil fuel age won’t end for a lack of coal, gas or oil. </p>
<p>So while humanity is not running out of fossil fuels, we <em>are</em> running out of options for the waste product, carbon dioxide – and running out of time to deal with it.</p>
<p>Countries that produce and export large amounts of fossil fuels must address this undeniable reality. We characterise three different ways they can do this. </p>
<p>The first is the “hell-for-leather” approach: extract, use and sell whatever fossil fuels you can while there’s still a market, and promote the global use of fossil fuels to extend the ride. This is the natural stance for companies focused solely on fossil fuel production. </p>
<p>Some countries that export fossil fuels are pursuing such strategies. In Australia, a statement by federal Resources Minister Keith Pitt <a href="https://www.minister.industry.gov.au/ministers/pitt/media-releases/coal-industry-has-strong-future-australia">this week</a> can be interpreted along such lines. </p>
<p>In this mindset, remaining fossil fuel deposits should be exploited to the maximum, at whatever cost. It emphasises specific business interests, while defining national interests in narrow and short-sighted terms. </p>
<p>It also disregards the global climate change objective and international relations with countries that emphasise climate concerns. In short, it risks train wrecks down the track. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/as-the-world-battles-to-slash-carbon-emissions-australia-considers-paying-dirty-coal-stations-to-stay-open-longer-166814">As the world battles to slash carbon emissions, Australia considers paying dirty coal stations to stay open longer</a>
</strong>
</em>
</p>
<hr>
<figure class="align-center ">
<img alt="man in high-vis vest and blue shirt" src="https://images.theconversation.com/files/420157/original/file-20210909-25-1hvgdoq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/420157/original/file-20210909-25-1hvgdoq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/420157/original/file-20210909-25-1hvgdoq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/420157/original/file-20210909-25-1hvgdoq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/420157/original/file-20210909-25-1hvgdoq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/420157/original/file-20210909-25-1hvgdoq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/420157/original/file-20210909-25-1hvgdoq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Resources Minister Keith Pitt says the future of Australia’s coal sector is strong.</span>
<span class="attribution"><span class="source">Aaron Bunch/AAP</span></span>
</figcaption>
</figure>
<p>A second approach is to concede fossil fuels are on a long-term <a href="https://theconversation.com/international-energy-agency-warns-against-new-fossil-fuel-projects-guess-what-australia-did-next-161178">downward trajectory</a>, due to climate change concerns and rapid improvements in clean technologies. It accepts this change is driven by consumers and there is nothing fossil fuel exporters can do about it. </p>
<p>The logical consequence is to prepare for the inevitable decline and cushion the transition. That could include using some revenue from fossil fuels to invest in a socially and environmentally sensitive transition. </p>
<p>Under this approach, the amount of fossil fuel available underground is simply irrelevant. The deposits are redundant – just like all those stones were at the end of the Stone Age. The question of what proportion must remain unexploited is of no particular interest.</p>
<p>A third option is to understand the challenge as a positive one: take the global shift away from fossil fuels as an opportunity to modernise and massively diversify the economy. </p>
<p>Taking this perspective, leaving coal in the ground is a positive step that helps nations and regions evolve in desirable ways and helps the world community, and future generations, deal with climate change. Not mining coal, then, takes on an ethical dimension – perhaps it can be seen as “ethi-coal”.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/climate-change-has-already-hit-australia-unless-we-act-now-a-hotter-drier-and-more-dangerous-future-awaits-ipcc-warns-165396">Climate change has already hit Australia. Unless we act now, a hotter, drier and more dangerous future awaits, IPCC warns</a>
</strong>
</em>
</p>
<hr>
<figure class="align-center ">
<img alt="two boys with arms around each other on cracked earth" src="https://images.theconversation.com/files/420158/original/file-20210909-27-1uxt8j4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/420158/original/file-20210909-27-1uxt8j4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/420158/original/file-20210909-27-1uxt8j4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/420158/original/file-20210909-27-1uxt8j4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/420158/original/file-20210909-27-1uxt8j4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/420158/original/file-20210909-27-1uxt8j4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/420158/original/file-20210909-27-1uxt8j4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The move away from fossil fuels can be seen as an opportunity to help future generations deal with climate change.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>Preparing for a post-fossil future</h2>
<p>Whichever lens one chooses to look through, clean technologies <em>will</em> displace the burning of coal, oil and gas. </p>
<p>In Australia, large corporations (and to a lesser extent, some employees and public finances) have done well out of coal and gas. But that’s far from the only way we can derive large export revenues. </p>
<p>Australia is exceptionally well placed to build up an energy and processing industry based on its practically limitless renewable energy potential, coupled with experience with and predisposition towards large resource industries. This could include <a href="https://theconversation.com/for-hydrogen-to-be-truly-clean-it-must-be-made-with-renewables-not-coal-128053">clean hydrogen</a> and even <a href="https://theconversation.com/green-steel-is-hailed-as-the-next-big-thing-in-australian-industry-heres-what-the-hype-is-all-about-160282">green steel</a>. </p>
<p>But to once again become dependent on just a few large industries, such as minerals or energy, should not be the goal here. Rather, we should use the global low-carbon transition as a platform for a large range of new industries. There are many opportunities in new technologies and practices. </p>
<p>So let’s keep our eye on the big picture: diversifying the economy into a broad range of activities with low environmental footprints, underpinned by modern infrastructure, top quality education and a strong social and health system. </p>
<p>Therein lies a desirable and economically sound future for Australia – one where we won’t be worrying one bit about all the coal left in the ground.</p><img src="https://counter.theconversation.com/content/167527/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Frank Jotzo leads and has led research projects funded by a variety of funders. None present a conflict of interest on this topic.</span></em></p><p class="fine-print"><em><span>Mark Howden does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>
The world is moving away fossil fuels, and there’s nothing Australia can do about it. Racing to dig up and sell whatever fossil fuels we can before the timer stops is not a future-proof strategy.
Frank Jotzo, Professor, Crawford School of Public Policy and Head of Energy, Institute for Climate Energy and Disaster Solutions, Australian National University
Mark Howden, Director, ANU Institute for Climate, Energy and Disaster Solutions, Australian National University
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/165242
2021-08-24T20:05:05Z
2021-08-24T20:05:05Z
From jet fuel to clothes, microbes can help us recycle carbon dioxide into everyday products
<figure><img src="https://images.theconversation.com/files/417561/original/file-20210824-27-1gisltd.jpeg?ixlib=rb-1.1.0&rect=15%2C55%2C5233%2C3439&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>The <a href="https://www.un.org/press/en/2021/sgsm20847.doc.htm">Intergovernmental Panel on Climate Change (IPCC) report</a> released earlier this month sounded a “code red for humanity”. At such a crucial time, we should draw on all possible solutions to combating global warming.</p>
<p>About <a href="https://doi.org/10.1039/C8EE01157E">one-quarter</a> of greenhouse gas emissions are associated with the manufacture of the products we use. While a small number of commercial uses for carbon dioxide exist — for instance in the beverage and chemical industries — the current demand isn’t enough to achieve meaningful carbon dioxide reduction. </p>
<p>As such, we need to find new ways to transform industrial manufacturing from being a carbon dioxide <em>source</em> to a carbon dioxide <em>user</em>.</p>
<p>The good news is that plastics, chemicals, cosmetics and many other products need a carbon source. If we could produce them using carbon dioxide instead of fossil hydrocarbons, we would be able to sequester <a href="https://doi.org/10.1016/j.joule.2018.04.018">billions of tonnes</a> of greenhouse gases per year. </p>
<p>How, you may ask? Well, biology already has a solution. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/there-arent-enough-trees-in-the-world-to-offset-societys-carbon-emissions-and-there-never-will-be-158181">There aren’t enough trees in the world to offset society’s carbon emissions – and there never will be</a>
</strong>
</em>
</p>
<hr>
<h2>Gas fermentation</h2>
<p>You may have heard of microscopic organisms, or microbes — we use them to make beer, spirits and bread. But we can also use them to create biofuels such as ethanol. </p>
<p>They typically need sugar as an input, which competes with human food consumption. However, there are other microbes called “acetogens” which can use carbon dioxide as their input to make several chemicals including ethanol. </p>
<p>Acetogens are thought to be one of the first life-forms on Earth. The ancient Earth’s atmosphere was very different to the atmosphere today — there was no oxygen, yet plentiful carbon dioxide. </p>
<p>Acetogens were able to recycle this carbon using chemical energy sources, such as hydrogen, in a process called gas fermentation. Today, acetogens are found in many anaerobic environments, such as in animals’ guts. </p>
<p>Not being able to use oxygen makes acetogens less efficient at building biomass; they are slow growers. But interestingly, it makes them more efficient producers. </p>
<p>For example, a typical food crop’s energy efficiency (where sunlight is turned into a product) may be around 1%. On the other hand, if solar energy was used to provide renewable hydrogen for use in gas fermentation (via acetogens), this process would have an overall energy efficiency closer to 10-15%.</p>
<p>This means acetogens are potentially up to twice as efficient as most current industrial processes — which makes them a cheaper and more environmentally friendly option. That is, if we can bring the technology to scale. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/417558/original/file-20210824-26-f3spkt.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/417558/original/file-20210824-26-f3spkt.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/417558/original/file-20210824-26-f3spkt.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/417558/original/file-20210824-26-f3spkt.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/417558/original/file-20210824-26-f3spkt.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/417558/original/file-20210824-26-f3spkt.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/417558/original/file-20210824-26-f3spkt.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/417558/original/file-20210824-26-f3spkt.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">About one-quarter of greenhouse gas emissions come from the manufacture of everyday products, while one-third come from electricity generation and another one-fifth come from transport.</span>
</figcaption>
</figure>
<h2>Sustainable carbon recycling</h2>
<p>Gas fermentation is <a href="https://www.cnbc.com/2018/07/27/lanzatech-turns-carbon-waste-into-ethanol-to-one-day-power-planes-cars.html">scaling up</a> in China, the United States and Europe. Industrial emissions of carbon monoxide and hydrogen are being recycled into ethanol to commercially produce <a href="https://techcrunch.com/2020/06/02/lanzajet-launches-to-make-renewable-jet-fuel-a-reality/">aviation fuel from 2022</a>, <a href="https://www.loreal.com/en/news/group/lanzatech-total-and-loreal/">plastic bottles from 2024</a> and even <a href="https://www.lanzatech.com/2021/07/13/lanzatech-and-lululemon-partner-to-create-the-first-fabric-using-recycled-carbon-emissions/">polyester clothes</a>.</p>
<p>In the future this could be expanded to produce chemicals needed to make rubber, plastics, paints and cosmetics, too.</p>
<p>But gas fermentation currently isn’t done commercially with carbon dioxide, despite this being a much larger emission source than carbon monoxide. In part this is because it poses an engineering and bioengineering challenge, but also because it’s expensive.</p>
<p>We recently published an economic assessment in <a href="https://doi.org/10.1016/j.watres.2021.117306">Water Research</a> to help chart a pathway towards widespread acetogen-carbon dioxide recycling.</p>
<p>We found economic barriers in producing some products, but not all. For instance, it is viable today to use carbon dioxide-acetogen fermentation to produce chemicals required to make perspex.</p>
<p>But unlike current commercial operations, this would be enabled by renewable hydrogen production. Increasing the availability of green hydrogen will greatly increase what we can do with gas fermentation.</p>
<h2>Looking ahead</h2>
<p>Australia has a competitive advantage and could be a leader in this technology. As host to the <a href="https://theconversation.com/why-green-hydrogen-but-not-grey-could-help-solve-climate-change-162987">world’s largest green-hydrogen projects</a>, we have the capacity to produce low-cost renewable hydrogen.</p>
<p>Underused renewable waste streams could also enable carbon recycling with acetogens. For instance, large amounts of biogas is produced at wastewater treatment plants and landfills. Currently it’s either burned as waste, or to generate heat and power.</p>
<p><a href="https://doi.org/10.1007/s10098-017-1341-1">Past research</a> shows us biogas can be converted (or “reformed”) into renewable hydrogen and carbon in a carbon-neutral process. </p>
<p>And we found this carbon and hydrogen could then be used in gas fermentation to make carbon-neutral products. This would provide as much as <a href="https://doi.org/10.1016/j.watres.2021.117306">12 times more</a> value than just burning biogas to generate heat and power.</p>
<p>The IPCC report shows carbon dioxide removal is <a href="https://www.ipcc.ch/site/assets/uploads/sites/2/2019/05/SR15_SPM_version_report_LR.pdf">required</a> to limit global warming to less than 2°C.</p>
<p>Carbon capture and storage is on most governments’ agendas. But if we change our mindset from viewing carbon as a waste product, then we can change our economic incentive from carbon disposal to carbon reuse. </p>
<p>Carbon dioxide stored underground has no value. If we harness its full potential by using it to manufacture products, this could support myriad industries as they move to sustainable production.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/our-ability-to-manufacture-minerals-could-transform-the-gem-market-medical-industries-and-even-help-suck-carbon-from-the-air-123853">Our ability to manufacture minerals could transform the gem market, medical industries and even help suck carbon from the air</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/165242/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jamin Wood receives funding from The Warwick and Nancy Olsen Scholarship and Research Training Program. </span></em></p><p class="fine-print"><em><span>Bernardino Virdis receives funding from the Australian Research Council. </span></em></p><p class="fine-print"><em><span>Shihu Hu receives funding from Australian Research Council. </span></em></p>
In ancient Earth’s atmosphere, microbes called acetogens were able to recycle carbon dioxide using chemical energy sources such as hydrogen.
Jamin Wood, PhD Candidate at the Australian Centre for Water and Environmental Biotechnology (formerly Advanced Water Management Centre), The University of Queensland
Bernardino Virdis, Senior Researcher at the Australian Centre for Water and Environmental Biotechnology (formerly Advanced Water Management Centre), The University of Queensland
Shihu Hu, Senior Research fellow at the Australian Centre for Water and Environmental Biotechnology (formerly Advanced Water Management Centre), The University of Queensland
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/161689
2021-05-28T09:14:30Z
2021-05-28T09:14:30Z
Climate change: six priorities for pulling carbon out of the air
<figure><img src="https://images.theconversation.com/files/403179/original/file-20210527-19-pnquvv.jpg?ixlib=rb-1.1.0&rect=401%2C290%2C3239%2C2471&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-vector/carbon-capture-technology-net-co2-footprint-1907627452">Dmitry Kovalchuk/Shutterstock</a></span></figcaption></figure><p>To reach net zero emissions by 2050, global emissions <a href="https://www.ipcc.ch/sr15/chapter/spm/">must be cut</a> faster and deeper than the world has yet managed. But even then, some hard-to-treat sources of pollution – in aviation, agriculture and cement making – may linger for longer than we would like. It will take time for clean alternatives to arrive and replace them. </p>
<p>That means the world also needs to find and ramp up ways of taking CO₂ out of the atmosphere to stabilise the climate. Just meeting the UK’s net zero target is likely to require the removal of <a href="https://www.theccc.org.uk/publication/sixth-carbon-budget/">100 million tonnes of CO₂ a year</a>, similar in size to current emissions from the country’s largest-emitting sector, road transport, but in reverse.</p>
<p>The UK government’s announcement of <a href="https://www.ukri.org/news/uk-invests-over-30m-in-large-scale-greenhouse-gas-removal/">£31.5 million</a> (US$44.7 million) in support for research and development of carbon removal is welcome. And while trials of new tech will help, there are many social issues that need to be tackled if removing greenhouse gases is to succeed.</p>
<p>Done right, carbon removal could be the perfect accompaniment to emissions cuts, bringing the climate back into balance. Done badly, it could be a dangerous distraction.</p>
<figure class="align-center ">
<img alt="Three smoke stacks belching white smoke from a coal-fired power plant." src="https://images.theconversation.com/files/403170/original/file-20210527-19-lx7t5c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/403170/original/file-20210527-19-lx7t5c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/403170/original/file-20210527-19-lx7t5c.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/403170/original/file-20210527-19-lx7t5c.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/403170/original/file-20210527-19-lx7t5c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/403170/original/file-20210527-19-lx7t5c.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/403170/original/file-20210527-19-lx7t5c.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Cutting emissions is vital. So is carbon removal.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/industrial-smoke-stack-coal-power-plant-607164341">Kamilpetran/Shutterstock</a></span>
</figcaption>
</figure>
<h2>Getting removal right</h2>
<p>Greenhouse gases can be removed from the atmosphere in several different ways. CO₂ can be captured by plants as they grow or absorbed by soils, minerals or chemicals, and locked up in the biosphere, oceans, underground, or even in long-lived products such as construction materials (including timber or aggregates).</p>
<p>These stores <a href="https://royalsociety.org/topics-policy/projects/greenhouse-gas-removal/">vary</a> in size and stability, and methods for getting carbon into them vary in cost and readiness. Trees, for instance, are literally a shovel-ready way to soak up carbon with many additional benefits. But the carbon they store can be released by fires, pests or logging. Storing CO₂ underground offers a more stable reservoir and could hold <a href="https://royalsociety.org/topics-policy/projects/greenhouse-gas-removal/">100 times as much</a>, but methods of injecting it from the air are expensive and at an early stage of development. Nevertheless, a raft of <a href="https://www.gov.uk/government/publications/direct-air-capture-and-other-greenhouse-gas-removal-technologies-competition/projects-selected-for-phase-1-of-the-direct-air-capture-and-greenhouse-gas-removal-programme">innovations</a>, <a href="https://www.xprize.org/prizes/elonmusk">competitions</a> and <a href="https://carbonplan.org/research/cdr-database">start-ups</a> are emerging.</p>
<p>Some experts worry that carbon removal could prove to be a mirage – particularly at the massive scales assumed in some pathways for reaching net zero – which distracts from the critical task of reducing emissions. So how do we get removals right?</p>
<p>As the scientists who will lead a national greenhouse gas removal hub, we’ve sketched out six priorities.</p>
<h2>1. A clear vision</h2>
<p>The UK government has yet to decide how much CO₂ it wants to remove from the atmosphere, the specific methods it prefers, and whether 2050 is an endpoint or a stepping stone to more removals beyond. A clear vision would help people see the merits of investing to remove CO₂, while also indicating which emissions sources should be stopped entirely.</p>
<h2>2. Public support</h2>
<p>Carbon removal at the scales under discussion will have big implications for communities and the environment. Entire landscapes and livelihoods will change. The government already aims to <a href="https://www.gov.uk/government/news/39-million-to-drive-innovative-tree-planting">plant enough trees</a> to cover twice the area of Bristol each year. </p>
<p>These changes need to offer <a href="https://royalsocietypublishing.org/doi/full/10.1098/rstb.2019.0120">other benefits</a> and align with the values of local people. People care not only about the removal techniques themselves, but also how <a href="https://www.nature.com/articles/s41467-019-08592-5">they are funded and supported</a>, and will want to see that reducing emissions remains <a href="https://www.nature.com/articles/s41558-020-0823-z?proof=t">the priority</a>. </p>
<p>Consultation is vital. Democratic processes, such as citizen assemblies, can help to find solutions that are attractive to different communities, increasing their legitimacy.</p>
<h2>3. Innovation</h2>
<p>The types of approaches that remove CO₂ permanently are at an early stage of development and cost hundreds of pounds per tonne of CO₂ removed. They are more expensive than most decarbonisation measures such as energy efficient lighting, insulation, solar and wind power or electric cars. Government support for research and development, and policies to encourage deployment are also crucial to stimulate innovation and bring down costs. </p>
<h2>4. Incentives</h2>
<p>How does a business earn a profit from removing CO₂ from the air? Except for <a href="https://www.gov.uk/guidance/create-woodland-overview#woodland-creation-funding-and-grants">trees</a>, there are no long-term, government-backed incentives for the removal and storage of carbon.</p>
<p>The UK government can learn from efforts in other countries. The <a href="https://www.globalccsinstitute.com/resources/publications-reports-research/the-lcfs-and-ccs-protocol-an-overview-for-policymakers-and-project-developers/">45Q tax rebate and Californian Low-Carbon Fuel Standard</a> and the Australian <a href="https://www.agriculture.gov.au/water/policy/carbon-farming-initiative">Carbon Farming Initiative</a> both incentivise businesses to capture and store CO₂.</p>
<p>Leaving the EU Common Agriculture Policy means the UK has its own opportunity to pay farmers to put carbon into their soils, trees and crops.</p>
<h2>5. Monitoring, reporting and verifying</h2>
<p>This is the vital but unglamorous work of ensuring carbon removal is properly documented and accurately measured. Without it, citizens would rightly worry whether any of this was real, and whether governments were simply handing out public money to companies for nothing in return.</p>
<p>Monitoring, reporting and verifying carbon storage in soil is a major challenge, requiring a <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/gcb.14815">complex system</a> of in-field sampling, satellites and models. Even for trees there are <a href="https://www.nature.com/articles/s41558-018-0283-x">gaps in international reporting</a> in many countries, and <a href="https://www.globalccsinstitute.com/wp-content/uploads/2021/01/Carbon-Removal-with-CCS-Technologies-Global-CCS-Institute-3.pdf">no agreed method</a> for reporting <a href="https://www.iea.org/reports/direct-air-capture">direct air capture</a> and storage, which uses chemicals to absorb CO₂ from the air.</p>
<h2>6. Decision-making</h2>
<p>A lot of information about CO₂ removal resides in academic literature and focuses on global-scale scenarios. But actually doing it will involve people ranging from local farmers to international financiers. All will need tools to help them make better decisions, from easy-to-read <a href="https://cdrprimer.org/">manuals</a> to improved <a href="https://www.nature.com/articles/s41467-019-10842-5">models</a>.</p>
<p>These priorities will guide our research, and will be things to look out for in the government’s emerging removal strategy. They need to involve businesses and citizens, not just policymakers and scientists.</p>
<p>Unfortunately, it is so late in the day that we can’t afford to get this wrong. But we are optimistic that there is plenty of scope to get it right.</p><img src="https://counter.theconversation.com/content/161689/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Cameron Hepburn receives funding from the UK government and UK research councils for work on accelerating the energy transition and on greenhouse gas removal. He is a member of the External Advisory Board of Shell plc, and the Advisory Board of Sarasin's Climate Active Fund. </span></em></p><p class="fine-print"><em><span>Steve Smith receives funding from the UK research councils for work on greenhouse gas removal. </span></em></p>
New UK-wide trials aim to discover the best ways to suck carbon from the air.
Cameron Hepburn, Professor of Environmental Economics, University of Oxford
Steve Smith, Executive Director, Oxford Net Zero, University of Oxford
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/157368
2021-04-22T04:25:34Z
2021-04-22T04:25:34Z
Climate scientists: concept of net zero is a dangerous trap
<figure><img src="https://images.theconversation.com/files/394790/original/file-20210413-17-67x47h.jpg?ixlib=rb-1.1.0&rect=0%2C1412%2C1794%2C1868&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://unsplash.com/photos/A_AQxGz9z5I">Thijs Stoop/Unsplash</a>, <a class="license" href="http://artlibre.org/licence/lal/en">FAL</a></span></figcaption></figure><p>Sometimes realisation comes in a blinding flash. Blurred outlines snap into shape and suddenly it all makes sense. Underneath such revelations is typically a much slower-dawning process. Doubts at the back of the mind grow. The sense of confusion that things cannot be made to fit together increases until something clicks. Or perhaps snaps. </p>
<p>Collectively we three authors of this article must have spent more than 80 years thinking about climate change. Why has it taken us so long to speak out about the obvious dangers of the concept of net zero? In our defence, the premise of net zero is deceptively simple – and we admit that it deceived us. </p>
<p>The threats of climate change are the direct result of there being too much carbon dioxide in the atmosphere. So it follows that we must stop emitting more and even remove some of it. This idea is central to the world’s current plan to avoid catastrophe. In fact, there are many suggestions as to how to actually do this, from mass tree planting, to high tech <a href="https://www.bbc.com/future/article/20210310-the-trillion-dollar-plan-to-capture-co2">direct air capture</a> devices that suck out carbon dioxide from the air. </p>
<iframe id="noa-web-audio-player" style="border: none" src="https://embed-player.newsoveraudio.com/v4?key=x84olp&id=https://theconversation.com/climate-scientists-concept-of-net-zero-is-a-dangerous-trap-157368&bgColor=F5F5F5&color=D8352A&playColor=D8352A" width="100%" height="110px"></iframe>
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Read more:
<a href="https://theconversation.com/there-arent-enough-trees-in-the-world-to-offset-societys-carbon-emissions-and-there-never-will-be-158181">There aren’t enough trees in the world to offset society’s carbon emissions – and there never will be</a>
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<p>The current consensus is that if we deploy these and other so-called “carbon dioxide removal” techniques at the same time as reducing our burning of fossil fuels, we can more rapidly halt global warming. Hopefully around the middle of this century we will achieve “net zero”. This is the point at which any residual emissions of greenhouse gases are balanced by technologies removing them from the atmosphere.</p>
<p>This is a great idea, in principle. Unfortunately, in practice it helps perpetuate a belief in <a href="https://www.carbonbrief.org/guest-post-a-brief-history-of-climate-targets-and-technological-promises">technological salvation</a> and <a href="https://www.ft.com/content/2d96502f-c34d-4150-aa36-9dc16ffdcad2">diminishes</a> the sense of urgency surrounding the need to curb emissions now. </p>
<p>We have arrived at the painful realisation that the idea of net zero has licensed a recklessly cavalier “burn now, pay later” approach which has seen carbon emissions continue to soar. It has also hastened the destruction of the natural world by <a href="https://www.theguardian.com/world/2021/jan/14/carbon-neutrality-is-a-fairy-tale-how-the-race-for-renewables-is-burning-europes-forests">increasing deforestation</a> today, and greatly increases the risk of further devastation in the future. </p>
<p>To understand how this has happened, how humanity has gambled its civilisation on no more than promises of future solutions, we must return to the late 1980s, when climate change broke out onto the international stage.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/394546/original/file-20210412-17-1o9nrlq.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/394546/original/file-20210412-17-1o9nrlq.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/394546/original/file-20210412-17-1o9nrlq.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/394546/original/file-20210412-17-1o9nrlq.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/394546/original/file-20210412-17-1o9nrlq.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/394546/original/file-20210412-17-1o9nrlq.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/394546/original/file-20210412-17-1o9nrlq.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<h2>Steps towards net zero</h2>
<p>On June 22 1988, James Hansen was the administrator of Nasa’s Goddard Institute for Space Studies, a prestigious appointment but someone largely unknown outside of academia.</p>
<p>By the afternoon of the 23rd he was well on the way to becoming the world’s most famous climate scientist. This was as a direct result of his <a href="https://www.sealevel.info/1988_Hansen_Senate_Testimony.html">testimony to the US congress</a>, when he forensically presented the evidence that the Earth’s climate was warming and that humans were the primary cause: “The greenhouse effect has been detected, and it is changing our climate now.”</p>
<p>If we had acted on Hansen’s testimony at the time, we would have been able to decarbonise our societies at a rate of around 2% a year in order to give us about a two-in-three chance of limiting warming to no more than 1.5°C. It would have been a huge challenge, but the main task at that time would have been to simply stop the accelerating use of fossil fuels while fairly sharing out future emissions. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/392826/original/file-20210331-15-4x9q0r.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Alt text" src="https://images.theconversation.com/files/392826/original/file-20210331-15-4x9q0r.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/392826/original/file-20210331-15-4x9q0r.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/392826/original/file-20210331-15-4x9q0r.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/392826/original/file-20210331-15-4x9q0r.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/392826/original/file-20210331-15-4x9q0r.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/392826/original/file-20210331-15-4x9q0r.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/392826/original/file-20210331-15-4x9q0r.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Graph demonstrating how fast mitigation has to happen to keep to 1.5°C.</span>
<span class="attribution"><a class="source" href="https://folk.universitetetioslo.no/roberan/img/GCB2018/PNG/s00_2018_Mitigation_Curves_1.5C.png">© Robbie Andrew</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
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<p>Four years later, there were glimmers of hope that this would be possible. During the 1992 <a href="https://www.un.org/en/conferences/environment/rio1992">Earth Summit in Rio</a>, all nations agreed to stabilise concentrations of greenhouse gases to ensure that they did not produce dangerous interference with the climate. The 1997 Kyoto Summit attempted to start to put that goal into practice. But as the years passed, the initial task of keeping us safe became increasingly harder given the continual increase in fossil fuel use. </p>
<p>It was around that time that the first computer models linking greenhouse gas emissions to impacts on different sectors of the economy were developed. These hybrid climate-economic models are known as <a href="https://www.oxfordbibliographies.com/view/document/obo-9780199363445/obo-9780199363445-0043.xml">Integrated Assessment Models</a>. They allowed modellers to link economic activity to the climate by, for example, exploring how changes in investments and technology could lead to changes in greenhouse gas emissions. </p>
<p>They seemed like a miracle: you could try out policies on a computer screen before implementing them, saving humanity costly experimentation. They rapidly emerged to become key guidance for climate policy. A primacy they maintain to this day. </p>
<p>Unfortunately, they also removed the need for deep critical thinking. Such models represent society as a web of idealised, <a href="https://www.carbonbrief.org/qa-how-integrated-assessment-models-are-used-to-study-climate-change">emotionless buyers and sellers</a> and thus ignore complex social and political realities, or even the impacts of climate change itself. Their implicit promise is that market-based approaches will always work. This meant that discussions about policies were limited to those most convenient to politicians: incremental changes to legislation and taxes.</p>
<hr>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/288776/original/file-20190820-170910-8bv1s7.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/288776/original/file-20190820-170910-8bv1s7.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/288776/original/file-20190820-170910-8bv1s7.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/288776/original/file-20190820-170910-8bv1s7.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/288776/original/file-20190820-170910-8bv1s7.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/288776/original/file-20190820-170910-8bv1s7.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/288776/original/file-20190820-170910-8bv1s7.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p><strong><em>This story is a collaboration between Conversation Insights and Apple News editors</em></strong>
<br><em>The Insights team generates <a href="https://theconversation.com/uk/topics/insights-series-71218">long-form journalism</a> and is working with academics from different backgrounds who have been engaged in projects to tackle societal and scientific challenges.</em> </p>
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<p>Around the time they were first developed, efforts were being made to <a href="https://web.archive.org/web/20121031094826/http://www.tyndall.ac.uk/content/climate-regime-hague-marrakech-saving-or-sinking-kyoto-protocol">secure US action on the climate</a> by allowing it to count carbon sinks of the country’s forests. The US argued that if it managed its forests well, it would be able to store a large amount of carbon in trees and soil which should be subtracted from its obligations to limit the burning of coal, oil and gas. In the end, the US largely got its way. Ironically, the concessions were all in vain, since the US senate never <a href="https://www.epw.senate.gov/public/index.cfm/2016/4/failures-of-kyoto-will-repeat-with-the-paris-climate-agreement">ratified the agreement</a>. </p>
<figure class="align-center ">
<img alt="Aerial view of autumn foliage." src="https://images.theconversation.com/files/393132/original/file-20210401-15-x0hygb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/393132/original/file-20210401-15-x0hygb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=316&fit=crop&dpr=1 600w, https://images.theconversation.com/files/393132/original/file-20210401-15-x0hygb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=316&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/393132/original/file-20210401-15-x0hygb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=316&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/393132/original/file-20210401-15-x0hygb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=398&fit=crop&dpr=1 754w, https://images.theconversation.com/files/393132/original/file-20210401-15-x0hygb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=398&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/393132/original/file-20210401-15-x0hygb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=398&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Forests such as this one in Maine, US, were suddenly counted in the carbon budget as an incentive for the US to join the Kyoto Agreement.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/autumn-foliage-maine-forest-brilliant-red-694925377">Inbound Horizons/Shutterstock</a></span>
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<p>Postulating a future with more trees could in effect offset the burning of coal, oil and gas now. As models could easily churn out numbers that saw atmospheric carbon dioxide go as low as one wanted, ever more sophisticated scenarios could be explored which reduced the perceived urgency to reduce fossil fuel use. By including carbon sinks in climate-economic models, a Pandora’s box had been opened.</p>
<p>It’s here we find the genesis of today’s net zero policies.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/393117/original/file-20210401-13-puplc5.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/393117/original/file-20210401-13-puplc5.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/393117/original/file-20210401-13-puplc5.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/393117/original/file-20210401-13-puplc5.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/393117/original/file-20210401-13-puplc5.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/393117/original/file-20210401-13-puplc5.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/393117/original/file-20210401-13-puplc5.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p>That said, most attention in the mid-1990s was focused on increasing energy efficiency and energy switching (such as the UK’s move from <a href="https://www.ft.com/content/a05d1dd4-dddd-11e9-9743-db5a370481bc">coal to gas</a>) and the potential of nuclear energy to deliver large amounts of carbon-free electricity. The hope was that such innovations would quickly reverse increases in fossil fuel emissions. </p>
<p>But by around the turn of the new millennium it was clear that such hopes were unfounded. Given their core assumption of incremental change, it was becoming more and more difficult for economic-climate models to find viable pathways to avoid dangerous climate change. In response, the models began to include more and more examples of <a href="https://theconversation.com/explainer-what-is-carbon-capture-and-storage-16052">carbon capture and storage</a>, a technology that could remove the carbon dioxide from coal-fired power stations and then store the captured carbon deep underground indefinitely.</p>
<p>This <a href="http://www.zeroco2.no/projects/val-verde-natural-gas-plants">had been shown</a> to be possible in principle: compressed carbon dioxide had been separated from fossil gas and then injected underground in a number of projects since the 1970s. These <a href="https://www.iea.org/commentaries/can-co2-eor-really-provide-carbon-negative-oil">Enhanced Oil Recovery schemes</a> were designed to force gases into oil wells in order to push oil towards drilling rigs and so allow more to be recovered – oil that would later be burnt, releasing even more carbon dioxide into the atmosphere.</p>
<p>Carbon capture and storage offered the twist that instead of using the carbon dioxide to extract more oil, the gas would instead be left underground and removed from the atmosphere. This promised breakthrough technology would allow <a href="https://oneill.indiana.edu/doc/research/coal_barnes.pdf">climate friendly coal</a> and so the continued use of this fossil fuel. But long before the world would witness any such schemes, the hypothetical process had been included in climate-economic models. In the end, the mere prospect of carbon capture and storage gave policy makers a way out of making the much needed cuts to greenhouse gas emissions.</p>
<h2>The rise of net zero</h2>
<p>When the international climate change community convened in <a href="https://unfccc.int/process-and-meetings/conferences/past-conferences/copenhagen-climate-change-conference-december-2009/copenhagen-climate-change-conference-december-2009">Copenhagen in 2009</a> it was clear that carbon capture and storage was not going to be sufficient for two reasons. </p>
<p>First, it still did not exist. There were <a href="https://www.newscientist.com/article/dn20761-uks-carbon-capture-failure-is-part-of-a-global-trend/">no carbon capture and storage facilities</a> in operation on any coal fired power station and no prospect the technology was going to have any impact on rising emissions from increased coal use in the foreseeable future. </p>
<p>The biggest barrier to implementation was essentially cost. The motivation to burn vast amounts of coal is to generate relatively cheap electricity. Retrofitting carbon scrubbers on existing power stations, building the infrastructure to pipe captured carbon, and developing suitable geological storage sites required huge sums of money. Consequently the only application of carbon capture in actual operation then – and now – is to use the trapped gas in enhanced oil recovery schemes. Beyond a <a href="https://www.power-technology.com/projects/sask-power-boundary/">single demonstrator</a>, there has never been any capture of carbon dioxide from a coal fired power station chimney with that captured carbon then being stored underground.</p>
<p>Just as important, by 2009 it was becoming increasingly clear that it would not be possible to make even the gradual reductions that policy makers demanded. That was the case even if carbon capture and storage was up and running. The amount of carbon dioxide that was being pumped into the air each year meant humanity was rapidly running out of time. </p>
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<p>With hopes for a solution to the climate crisis fading again, another magic bullet was required. A technology was needed not only to slow down the increasing concentrations of carbon dioxide in the atmosphere, but actually reverse it. In response, the climate-economic modelling community – already able to include plant-based carbon sinks and geological carbon storage in their models – increasingly adopted the “solution” of combining the two.</p>
<p>So it was that Bioenergy Carbon Capture and Storage, or <a href="https://www.carbonbrief.org/beccs-the-story-of-climate-changes-saviour-technology">BECCS</a>, rapidly emerged as the new saviour technology. By burning “replaceable” biomass such as wood, crops, and agricultural waste instead of coal in power stations, and then capturing the carbon dioxide from the power station chimney and storing it underground, BECCS could produce electricity at the same time as removing carbon dioxide from the atmosphere. That’s because as biomass such as trees grow, they suck in carbon dioxide from the atmosphere. By planting trees and other bioenergy crops and storing carbon dioxide released when they are burnt, more carbon could be removed from the atmosphere.</p>
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<p>With this new solution in hand the international community regrouped from repeated failures to mount another attempt at reining in our dangerous interference with the climate. The scene was set for the crucial 2015 climate conference in Paris.</p>
<h2>A Parisian false dawn</h2>
<p>As its general secretary brought the 21st United Nations conference on climate change to an end, a great roar issued from the crowd. People leaped to their feet, strangers embraced, tears welled up in eyes bloodshot from lack of sleep. </p>
<p>The emotions on display on December 13, 2015 were not just for the cameras. After weeks of gruelling high-level negotiations in Paris a breakthrough had finally <a href="https://unfccc.int/process-and-meetings/the-paris-agreement/the-paris-agreement">been achieved</a>. Against all expectations, after decades of false starts and failures, the international community had finally agreed to do what it took to limit global warming to well below 2°C, preferably to 1.5°C, compared to pre-industrial levels. </p>
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<p>The Paris Agreement was a stunning victory for those most at risk from climate change. Rich industrialised nations will be increasingly impacted as global temperatures rise. But it’s the low lying island states such as the Maldives and the Marshall Islands that are at imminent existential risk. As a later UN <a href="https://www.ipcc.ch/sr15/">special report</a> made clear, if the Paris Agreement was unable to limit global warming to 1.5°C, the number of lives lost to more intense storms, fires, heatwaves, famines and floods would significantly increase.</p>
<p>But dig a little deeper and you could find another emotion lurking within delegates on December 13. Doubt. We struggle to name any climate scientist who at that time thought the Paris Agreement was feasible. We have since been told by some scientists that the Paris Agreement was “of course important for climate justice but unworkable” and “a complete shock, no one thought limiting to 1.5°C was possible”. Rather than being able to limit warming to 1.5°C, a senior academic involved in the IPCC concluded we were heading beyond <a href="https://theconversation.com/climate-change-weve-created-a-civilisation-hell-bent-on-destroying-itself-im-terrified-writes-earth-scientist-113055">3°C by the end of this century</a>. </p>
<p>Instead of confront our doubts, we scientists decided to construct ever more elaborate fantasy worlds in which we would be safe. The price to pay for our cowardice: having to keep our mouths shut about the ever growing absurdity of the required planetary-scale carbon dioxide removal.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/394549/original/file-20210412-13-1n4dgym.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/394549/original/file-20210412-13-1n4dgym.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/394549/original/file-20210412-13-1n4dgym.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/394549/original/file-20210412-13-1n4dgym.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/394549/original/file-20210412-13-1n4dgym.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/394549/original/file-20210412-13-1n4dgym.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/394549/original/file-20210412-13-1n4dgym.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p>Taking centre stage was BECCS because at the time this was the only way climate-economic models could find scenarios that would be consistent with the Paris Agreement. Rather than stabilise, global emissions of carbon dioxide had increased some 60% since 1992.</p>
<p>Alas, BECCS, just like all the previous solutions, was too good to be true.</p>
<p>Across the scenarios produced by the Intergovernmental Panel on Climate Change (IPCC) with a 66% or better chance of limiting temperature increase to 1.5°C, BECCS would need to remove 12 billion tonnes of carbon dioxide each year. BECCS at this scale would require massive planting schemes for trees and bioenergy crops. </p>
<p>The Earth certainly needs more trees. Humanity has cut down some <a href="https://theconversation.com/three-trillion-trees-live-on-earth-but-there-would-be-twice-as-many-without-humans-46914">three trillion</a> since we first started farming some 13,000 years ago. But rather than allow ecosystems to recover from human impacts and forests to regrow, BECCS generally refers to dedicated industrial-scale plantations regularly harvested for bioenergy rather than carbon stored away in forest trunks, roots and soils. </p>
<p>Currently, the two most <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7320919/">efficient</a> biofuels are sugarcane for bioethanol and palm oil for biodiesel – both grown in the tropics. Endless rows of such fast growing monoculture trees or other bioenergy crops harvested at frequent intervals <a href="https://www.politico.com/news/magazine/2021/03/26/biomass-carbon-climate-politics-477620">devastate biodiversity</a>. </p>
<p>It has been estimated that BECCS would demand between <a href="https://www.imperial.ac.uk/media/imperial-college/grantham-institute/public/publications/briefing-papers/BECCS-deployment---a-reality-check.pdf">0.4 and 1.2 billion hectares of land</a>. That’s 25% to 80% of all the land currently under cultivation. How will that be achieved at the same time as feeding 8-10 billion people around the middle of the century or without destroying native vegetation and biodiversity? </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/carbon-capture-on-power-stations-burning-woodchips-is-not-the-green-gamechanger-many-think-it-is-110475">Carbon capture on power stations burning woodchips is not the green gamechanger many think it is</a>
</strong>
</em>
</p>
<hr>
<p>Growing billions of trees would consume <a href="https://www.nature.com/articles/s41467-021-21640-3">vast amounts</a> of water – in some places where <a href="https://theconversation.com/planting-trees-must-be-done-with-care-it-can-create-more-problems-than-it-addresses-128259">people are already thirsty</a>. Increasing forest cover in higher latitudes can have an <a href="https://agupubs.onlinelibrary.wiley.com/doi/pdfdirect/10.1002/2016GL071459">overall warming effect</a> because replacing grassland or fields with forests means the land surface becomes darker. This darker land absorbs more energy from the Sun and so temperatures rise. Focusing on developing vast plantations in poorer tropical nations comes with real risks of people being driven <a href="https://www.researchgate.net/publication/307509892_Stakeholders_and_tropical_reforestation_challenges_tradeoffs_and_strategies_in_dynamic_environments">off their lands</a>. </p>
<p>And it is often forgotten that trees and the land in general already soak up and store away <a href="https://www.globalcarbonproject.org/carbonbudget/20/publications.htm">vast amounts of carbon</a> through what is called the natural terrestrial carbon sink. Interfering with it could both disrupt the sink and lead to <a href="https://theconversation.com/is-the-eu-cheating-on-its-net-zero-emissions-plan-heres-what-the-science-says-147047">double accounting</a>.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/396503/original/file-20210422-21-1suqm95.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/396503/original/file-20210422-21-1suqm95.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/396503/original/file-20210422-21-1suqm95.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/396503/original/file-20210422-21-1suqm95.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/396503/original/file-20210422-21-1suqm95.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/396503/original/file-20210422-21-1suqm95.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/396503/original/file-20210422-21-1suqm95.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
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<p>As these impacts are becoming better understood, the sense of optimism around BECCS <a href="https://www.carbonbrief.org/in-depth-experts-assess-the-feasibility-of-negative-emissions">has diminished</a>. </p>
<h2>Pipe dreams</h2>
<p>Given the dawning realisation of how difficult Paris would be in the light of ever rising emissions and limited potential of BECCS, a new buzzword emerged in policy circles: the “<a href="https://www.nature.com/articles/s41598-017-14503-9">overshoot scenario</a>”. Temperatures would be allowed to go beyond 1.5°C in the near term, but then be brought down with a range of carbon dioxide removal by the end of the century. This means that net zero actually means <a href="https://www.iea.org/commentaries/going-carbon-negative-what-are-the-technology-options">carbon negative</a>. Within a few decades, we will need to transform our civilisation from one that currently pumps out 40 billion tons of carbon dioxide into the atmosphere each year, to one that produces a net removal of tens of billions.</p>
<p><a href="https://www.nytimes.com/2020/02/12/opinion/trump-climate-change-trees.html">Mass tree planting</a>, for bioenergy or as an attempt at offsetting, had been the latest attempt to stall cuts in fossil fuel use. But the ever-increasing need for carbon removal was calling for more. This is why the idea of direct air capture, now being <a href="https://www.wri.org/blog/2020/03/to-unlock-the-potential-of-direct-air-capture-we-must-invest-now">touted by some</a> as the most promising technology out there, has taken hold. It is generally more benign to ecosystems because it requires <a href="https://hoffmanncentre.chathamhouse.org/article/betting-on-beccs-exploring-land-based-negative-emissions-technologies/">significantly less land</a> to operate than BECCS, including the land needed to power them using wind or solar panels.</p>
<p>Unfortunately, it is widely believed that direct air capture, because of its <a href="https://www.wri.org/blog/2021/01/direct-air-capture-definition-cost-considerations">exorbitant costs and energy demand</a>, if it ever becomes feasible to be deployed at scale, will not be able to <a href="https://www.nature.com/articles/s41558-020-0885-y">compete with BECCS</a> with its voracious appetite for prime agricultural land.</p>
<p>It should now be getting clear where the journey is heading. As the mirage of each magical technical solution disappears, another equally unworkable alternative pops up to take its place. The next is already on the horizon – and it’s even more ghastly. Once we realise net zero will not happen in time or even at all, <a href="https://theconversation.com/why-you-need-to-get-involved-in-the-geoengineering-debate-now-85619">geoengineering</a> – the deliberate and large scale intervention in the Earth’s climate system – will probably be invoked as the solution to limit temperature increases.</p>
<p>One of the most researched geoengineering ideas is <a href="https://theconversation.com/blocking-out-the-sun-wont-fix-climate-change-but-it-could-buy-us-time-50818">solar radiation management</a> – the injection of millions of tons of sulphuric acid <a href="https://www.nature.com/articles/s41559-017-0431-0">into the stratosphere</a> that will reflect some of the Sun’s energy away from the Earth. It is a wild idea, but some academics and politicians are deadly serious, despite significant <a href="https://www.nae.edu/19579/19582/21020/228883/228936/Benefits-and-Risks-of-Stratospheric-Solar-Radiation-Management-for-Climate-Intervention-Geoengineering">risks</a>. The US National Academies of Sciences, for example, has recommended <a href="https://www.nationalacademies.org/news/2021/03/new-report-says-u-s-should-cautiously-pursue-solar-geoengineering-research-to-better-understand-options-for-responding-to-climate-change-risks">allocating up to US$200 million</a> over the next five years to explore how geoengineering could be deployed and regulated. Funding and research in this area is sure to significantly increase. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/393121/original/file-20210401-21-g3swz5.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/393121/original/file-20210401-21-g3swz5.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/393121/original/file-20210401-21-g3swz5.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/393121/original/file-20210401-21-g3swz5.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/393121/original/file-20210401-21-g3swz5.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/393121/original/file-20210401-21-g3swz5.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/393121/original/file-20210401-21-g3swz5.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
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<h2>Difficult truths</h2>
<p>In principle there is nothing wrong or dangerous about carbon dioxide removal proposals. In fact developing ways of reducing concentrations of carbon dioxide can feel tremendously exciting. You are using science and engineering to save humanity from disaster. What you are doing is important. There is also the realisation that carbon removal will be needed to mop up some of the emissions from sectors such as aviation and cement production. So there will be some small role for a number of different carbon dioxide removal approaches. </p>
<p>The problems come when it is assumed that these can be deployed at vast scale. This effectively serves as a blank cheque for the continued burning of fossil fuels and the acceleration of habitat destruction.</p>
<p>Carbon reduction technologies and geoengineering should be seen as a sort of ejector seat that could propel humanity away from rapid and catastrophic environmental change. Just like an ejector seat in a jet aircraft, it should only be used as the very last resort. However, policymakers and businesses appear to be entirely serious about deploying highly speculative technologies as a way to land our civilisation at a sustainable destination. In fact, these are no more than fairy tales. </p>
<figure class="align-center ">
<img alt="Crowds of young people hold placards." src="https://images.theconversation.com/files/393130/original/file-20210401-17-ntcpsp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/393130/original/file-20210401-17-ntcpsp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/393130/original/file-20210401-17-ntcpsp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/393130/original/file-20210401-17-ntcpsp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/393130/original/file-20210401-17-ntcpsp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/393130/original/file-20210401-17-ntcpsp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/393130/original/file-20210401-17-ntcpsp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">‘There is no Planet B’: children in Birmingham, UK, protest against the climate crisis.</span>
<span class="attribution"><a class="source" href="https://unsplash.com/photos/wwb1TJMd1BQ">Callum Shaw/Unsplash</a>, <a class="license" href="http://artlibre.org/licence/lal/en">FAL</a></span>
</figcaption>
</figure>
<p>The only way to keep humanity safe is the immediate and sustained radical cuts to greenhouse gas emissions in a <a href="https://yaleclimateconnections.org/2020/07/what-is-climate-justice/">socially just way</a>.</p>
<p>Academics typically see themselves as servants to society. Indeed, many are employed as civil servants. Those working at the climate science and policy interface desperately wrestle with an increasingly difficult problem. Similarly, those that champion net zero as a way of breaking through barriers holding back effective action on the climate also work with the very best of intentions. </p>
<p>The tragedy is that their collective efforts were never able to mount an effective challenge to a climate policy process that would only allow a narrow range of scenarios to be explored. </p>
<p>Most academics feel distinctly uncomfortable stepping over the invisible line that separates their day job from wider social and political concerns. There are genuine fears that being seen as advocates for or against particular issues could threaten their perceived independence. Scientists are one of the most trusted professions. Trust is very hard to build and easy to destroy.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/394551/original/file-20210412-13-bllb2g.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/394551/original/file-20210412-13-bllb2g.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/394551/original/file-20210412-13-bllb2g.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/394551/original/file-20210412-13-bllb2g.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/394551/original/file-20210412-13-bllb2g.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/394551/original/file-20210412-13-bllb2g.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/394551/original/file-20210412-13-bllb2g.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p>But there is another invisible line, the one that separates maintaining academic integrity and self-censorship. As scientists, we are taught to be sceptical, to subject hypotheses to rigorous tests and interrogation. But when it comes to perhaps the greatest challenge humanity faces, we often show a dangerous lack of critical analysis. </p>
<p>In private, scientists express significant scepticism about the Paris Agreement, BECCS, <a href="https://www.ft.com/content/2d96502f-c34d-4150-aa36-9dc16ffdcad2">offsetting</a>, geoengineering and net zero. Apart from <a href="https://www.nature.com/news/polopoly_fs/1.19074!/menu/main/topColumns/topLeftColumn/pdf/528437a.pdf">some notable exceptions</a>, in public we quietly go about our work, apply for funding, publish papers and teach. The path to disastrous climate change is paved with feasibility studies and impact assessments. </p>
<p>Rather than acknowledge the seriousness of our situation, we instead continue to participate in the fantasy of net zero. What will we do when reality bites? What will we say to our friends and loved ones about our failure to speak out now?</p>
<p>The time has come to voice our fears and be honest with wider society. Current net zero policies will not keep warming to within 1.5°C because they were never intended to. They were and still are driven by a need to protect business as usual, not the climate. If we want to keep people safe then large and sustained cuts to carbon emissions need to happen now. That is the very simple acid test that must be applied to all climate policies. The time for wishful thinking is over.</p>
<hr>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/313478/original/file-20200204-41481-1n8vco4.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/313478/original/file-20200204-41481-1n8vco4.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=112&fit=crop&dpr=1 600w, https://images.theconversation.com/files/313478/original/file-20200204-41481-1n8vco4.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=112&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/313478/original/file-20200204-41481-1n8vco4.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=112&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/313478/original/file-20200204-41481-1n8vco4.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=140&fit=crop&dpr=1 754w, https://images.theconversation.com/files/313478/original/file-20200204-41481-1n8vco4.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=140&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/313478/original/file-20200204-41481-1n8vco4.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=140&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p><em>For you: more from our <a href="https://theconversation.com/uk/topics/insights-series-71218?utm_source=TCUK&utm_medium=linkback&utm_campaign=TCUKengagement&utm_content=InsightsUK">Insights series</a>:</em></p>
<ul>
<li><p><em><a href="https://theconversation.com/there-arent-enough-trees-in-the-world-to-offset-societys-carbon-emissions-and-there-never-will-be-158181?utm_source=TCUK&utm_medium=linkback&utm_campaign=TCUKengagement&utm_content=InsightsUK">There aren’t enough trees in the world to offset society’s carbon emissions – and there never will be</a></em></p></li>
<li><p><em><a href="https://theconversation.com/how-we-discovered-a-hidden-world-of-fungi-inside-the-worlds-biggest-seed-bank-156051?utm_source=TCUK&utm_medium=linkback&utm_campaign=TCUKengagement&utm_content=InsightsUK">How we discovered a hidden world of fungi inside the world’s biggest seed bank</a></em></p></li>
<li><p><em><a href="https://theconversation.com/prehistoric-communities-off-the-coast-of-britain-embraced-rising-seas-what-this-means-for-todays-island-nations-147879?utm_source=TCUK&utm_medium=linkback&utm_campaign=TCUKengagement&utm_content=InsightsUK">Prehistoric communities off the coast of Britain embraced rising seas – what this means for today’s island nations</a></em></p></li>
</ul>
<p><em>To hear about new Insights articles, join the hundreds of thousands of people who value The Conversation’s evidence-based news. <a href="https://theconversation.com/uk/newsletters/the-daily-newsletter-2?utm_source=TCUK&utm_medium=linkback&utm_campaign=TCUKengagement&utm_content=InsightsUK"><strong>Subscribe to our newsletter</strong></a>.</em></p><img src="https://counter.theconversation.com/content/157368/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>
Prominent academics, including a former IPCC chair, round on governments worldwide for using the concept of net zero emissions to ‘greenwash’ their lack of commitment to solving global warming.
James Dyke, Associate Professor in Earth System Science, University of Exeter
Robert Watson, Emeritus Professor in Environmental Sciences, University of East Anglia
Wolfgang Knorr, Senior Research Scientist, Physical Geography and Ecosystem Science, Lund University
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/129499
2020-01-20T15:34:34Z
2020-01-20T15:34:34Z
Five ways to turn CO₂ from pollution to a valuable product
<figure><img src="https://images.theconversation.com/files/310889/original/file-20200120-69547-xe9j36.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C8000%2C4000&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/industrial-factory-chimneys-on-background-money-1316977286">1599686sv/Shutterstock</a></span></figcaption></figure><p>It’s far easier to avoid burning fossil fuels than it is to clean up CO₂ emissions once they’re in the Earth’s atmosphere. But the world no longer has the luxury of choice – drastic emission reductions and rapid CO₂ removal and storage <a href="https://www.ipcc.ch/sr15/">will both be necessary</a> to avoid the worst impacts of global heating.</p>
<p>What if, instead of wasting all that CO₂, it could be turned into something useful? There’s currently little economic incentive for industries that emit CO₂ to capture it, let alone to draw it directly down from the atmosphere. Identifying valuable products and how to make them might kickstart CO₂ removal on an industrial scale, and help bring down emissions in the process. In <a href="https://www.nature.com/articles/s41586-019-1681-6">our recent paper</a>, we set out to clarify what these processes and products might be. </p>
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Read more:
<a href="https://theconversation.com/co-shortage-why-cant-we-just-pull-carbon-dioxide-out-of-the-air-99255">CO₂ shortage: why can't we just pull carbon dioxide out of the air?</a>
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<p>We considered processes that use CO₂ captured from industrial emissions, and also biological processes that can directly draw down CO₂ from the air. We projected that between one and ten gigatonnes of CO₂ could be utilised per year by 2050, at costs of under USD$100 (£77) per tonne of CO₂. Humans currently emit 37 gigatonnes of CO₂ a year, and we need to reduce our impact to net zero by around 2050. Some <a href="https://science.sciencemag.org/content/355/6331/1269.full">estimates</a> suggest this might mean removing around ten gigatonnes of CO₂ a year from 2050 onward. Some of these ideas for using CO₂, if implemented properly, could play a role in making that more economically viable.</p>
<p>Some ideas for using CO₂ might not get off the drawing board. But with the right investment and incentives, others may move from niche research projects into credible plans, and from the work of small businesses to the goal of entire industries. Here is a selection of the ways that one person’s pollution could become another’s product.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/310903/original/file-20200120-69531-106mjjf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/310903/original/file-20200120-69531-106mjjf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/310903/original/file-20200120-69531-106mjjf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/310903/original/file-20200120-69531-106mjjf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/310903/original/file-20200120-69531-106mjjf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/310903/original/file-20200120-69531-106mjjf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/310903/original/file-20200120-69531-106mjjf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Creating a commodity out of carbon could help kickstart its removal from the atmosphere.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/industrial-factory-chimneys-on-background-money-1316977286">Elevate on Unsplash/Shutterstock</a></span>
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<h2>1. Make buildings</h2>
<p>There are several ways in which buildings can be constructed with materials made from CO₂. The first is obvious: use wood. Growing and sustainably harvesting trees for building means that CO₂ is taken from the atmosphere, converted into a valuable commercial product, and stored as carbon in long-lived buildings. </p>
<p>It also reduces demand for cement, which is responsible for <a href="https://theconversation.com/supermud-bricks-could-help-tackle-the-worlds-housing-crisis-and-cut-carbon-emissions-that-cause-climate-change-95628">10-15% of global greenhouse gas emissions through its production</a>. New technologies, such as cross-laminated timber or acetylated wood, are making this substitution ever easier. </p>
<p>The second way is to use and then store CO₂ in concrete-making processes, by <a href="https://www.solidiatech.com/">curing cement</a> or in the <a href="http://c8s.co.uk/">manufacture</a> of other ingredients like <a href="http://www.greenspec.co.uk/building-design/aggregates-for-concrete/">aggregate</a>. </p>
<h2>2. Create plastic products</h2>
<p>CO₂ <a href="http://econic-technologies.com/">can be used in polymers</a> to make durable plastics for cars and buildings. Around <a href="https://advances.sciencemag.org/content/3/7/e1700782">60% of plastics have applications in sectors other than packaging</a>. Plastics made from CO₂ could displace <a href="https://theconversation.com/fossil-fuel-industry-sees-the-future-in-hard-to-recycle-plastic-123631">plastic products made from fossil fuels</a> for these sectors, particularly as they don’t require toxic or dirty ingredients such as phosgenes or epoxides, and can be cheaper to make than fossil-fuel based materials. Because the CO₂ molecule is a stable part of the backbone of the polymer, it can be stored in these materials for as long as they last.</p>
<h2>3. Make fuel or fertilisers</h2>
<p>CO₂ can be used as a feedstock for many chemical processes, with hundreds of potential end products, including hydrocarbon fuels and urea fertilisers. </p>
<p>Fuels made from CO₂ can exist in the form of methanol as well as more complex products like so-called <a href="https://auto.howstuffworks.com/fuel-efficiency/biofuels/synfuel.htm">synfuels</a>. These fuels can often be blended or moved around using existing infrastructure like pipes and tankers. And although CO₂ fuels are currently very costly to manufacture, in the future they might be valuable in niches like aviation or long-distance shipping, which are <a href="https://theconversation.com/two-crucial-omissions-that-could-jeopardise-paris-climate-deal-52341">more difficult to decarbonise</a> than trains and cars because they need fuels with higher energy densities.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/310904/original/file-20200120-69543-13w5cxf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/310904/original/file-20200120-69543-13w5cxf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/310904/original/file-20200120-69543-13w5cxf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/310904/original/file-20200120-69543-13w5cxf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/310904/original/file-20200120-69543-13w5cxf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/310904/original/file-20200120-69543-13w5cxf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/310904/original/file-20200120-69543-13w5cxf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">While it will be comparatively easy for cars and trains to undergo electrification, aeroplanes will still need liquid fuels with high energy densities for a while.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/amsterdam-netherlands-november-13-2017-plane-789771859">Milosz Maslanka/Shutterstock</a></span>
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<p>If the CO₂ product is a fuel or a fertiliser, the CO₂ ends up back in the atmosphere once used. While two uses of the carbon is better than one, if the carbon atom originally came from a fossil fuel, it’s not a long-term solution. To be climate neutral, the CO₂ feedstock will have to be sourced from the air – so the CO₂ is taken from the atmosphere, made into fuel, and then emitted back to the atmosphere. This is currently expensive and technically challenging. Crucially, the energy required for this process also needs to be renewable. </p>
<h2>4. Increase crop yields</h2>
<p><a href="https://www.sciencedirect.com/science/article/pii/S0167198717302271">There’s emerging evidence</a> that increasing the amount of carbon in soils can also increase crop yields. This is a natural form of CO₂ utilisation that already happens – scientists and farmers can just give it a helping hand. One particularly promising way is by using biochar – plant material that has been converted into a stable form of organic carbon via a process known as pyrolysis. Biochar buried in soils could store carbon for the long term and increase crop yields. </p>
<p>The general benefits of <a href="https://theconversation.com/soil-is-our-best-ally-in-the-fight-against-climate-change-but-were-fast-running-out-of-it-128166">replenishing and maintaining carbon in the soil</a> are well established, but using soil as a store of carbon is challenging because it is easily disturbed. </p>
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Read more:
<a href="https://theconversation.com/we-need-more-carbon-in-our-soil-to-help-australian-farmers-through-the-drought-102991">We need more carbon in our soil to help Australian farmers through the drought</a>
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<h2>5. Extract more oil</h2>
<p>Counter-intuitively, it’s possible to both produce oil and store CO₂. That’s because injecting CO₂ into an oil well increases the amount of oil that can be recovered – so-called “CO₂ enhanced oil recovery”. </p>
<p><a href="https://pubs.acs.org/doi/10.1021/es504600q">It is actually possible</a> to operate the well so that more CO₂ is put into it than is emitted in the process of producing the oil and burning it. But policy changes would be needed to incentivise this – oil companies would not do it otherwise. And it’s a temporary fix. In a world that has fully decarbonised, demand for fossil oil should be close to zero.</p>
<p>Nonetheless, this could be a short-term way to <a href="https://www.iea.org/commentaries/us-budget-bill-may-help-carbon-capture-get-back-on-track">stimulate much needed demand for CO₂ capture</a>, as emitters could sell their waste CO₂ to oil producers.</p>
<p>All these options for using CO₂ have potential, but making them a reality will need a clear understanding of the possible unintended consequences. Many could be failures, so it’d be unwise to rely solely on any one of them, but instead, spread bets widely.</p>
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<img alt="" src="https://images.theconversation.com/files/263883/original/file-20190314-28475-1mzxjur.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/263883/original/file-20190314-28475-1mzxjur.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=140&fit=crop&dpr=1 600w, https://images.theconversation.com/files/263883/original/file-20190314-28475-1mzxjur.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=140&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/263883/original/file-20190314-28475-1mzxjur.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=140&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/263883/original/file-20190314-28475-1mzxjur.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=176&fit=crop&dpr=1 754w, https://images.theconversation.com/files/263883/original/file-20190314-28475-1mzxjur.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=176&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/263883/original/file-20190314-28475-1mzxjur.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=176&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p><em><a href="https://theconversation.com/imagine-newsletter-researchers-think-of-a-world-with-climate-action-113443?utm_source=TCUK&utm_medium=linkback&utm_campaign=TCUKengagement&utm_content=Imagineheader1129499">Click here to subscribe to our climate action newsletter. Climate change is inevitable. Our response to it isn’t.</a></em></p><img src="https://counter.theconversation.com/content/129499/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Cameron Hepburn receives funding from the Oxford Martin School, the UK government (UKRI, BEIS, FCO), the US government (IARPA), the Nature Conservancy and Partners for a New Economy. He is a Director of Aurora Energy Research Limited and Vivid Economics Limited. </span></em></p><p class="fine-print"><em><span>Ella Adlen does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>
CO₂ will need to be removed from the atmosphere to avoid catastrophic heating. Can the process be incentivised?
Ella Adlen, Research and Programmes Manager, Oxford Martin School, University of Oxford
Cameron Hepburn, Professor of Environmental Economics, University of Oxford
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/123853
2019-10-18T05:52:59Z
2019-10-18T05:52:59Z
Our ability to manufacture minerals could transform the gem market, medical industries and even help suck carbon from the air
<figure><img src="https://images.theconversation.com/files/297110/original/file-20191015-98636-u508ph.JPG?ixlib=rb-1.1.0&rect=0%2C5%2C3964%2C2988&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Pictured is a slag pile at Broken Hill in New South Wales. Slag is a man-made waste product created during smelting. </span> <span class="attribution"><span class="source">Anita Parbhakar-Fox</span>, <span class="license">Author provided</span></span></figcaption></figure><p>Last month, scientists <a href="https://www.theage.com.au/national/victoria/this-meteorite-came-from-the-core-of-another-planet-inside-it-a-new-mineral-20190830-p52mhg.html">uncovered</a> a mineral called Edscottite. Minerals are solid, naturally occurring substances that are not living, such as quartz or haematite. This new mineral was discovered after an examination of the <a href="https://collections.museumvictoria.com.au/specimens/328">Wedderburn Meteorite</a>, a metallic-looking rock found in Central Victoria back in 1951. </p>
<p>Edscottite is made of iron and carbon, and was likely formed within the core of another planet. It’s a “true” mineral, meaning one which is naturally occurring and formed by geological processes either on Earth or in outer-space.</p>
<p>But while the Wedderburn Meteorite held the first-known discovery of Edscottite, other new mineral discoveries have been made on Earth, of substances formed as a result of human activities such as mining and mineral processing. These are called anthropogenic minerals.</p>
<p>While true minerals comprise the majority of the approximately 5,200 known minerals, there are about <a href="https://deepcarbon.net/feature/humanitys-minerals">208</a> human-made minerals which have been approved as minerals by the International Mineralogical Association. </p>
<p>Some are made on purpose and others are by-products. Either way, the ability to manufacture minerals has vast implications for the future of our rapidly growing population.</p>
<h2>Modern-day alchemy</h2>
<p>Climate change is one of the biggest challenges we face. While governments debate the future of coal-burning power stations, carbon dioxide continues to be released into the atmosphere. We need innovative strategies to capture it. </p>
<p>Actively manufacturing minerals such as <a href="http://www.webmineral.com/data/Nesquehonite.shtml#.XYL-sGkzaCg">nesquehonite</a> is one possible approach. It has applications in building and construction, and making it requires removing carbon dioxide from the atmosphere.</p>
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<strong>
Read more:
<a href="https://theconversation.com/climate-explained-why-carbon-dioxide-has-such-outsized-influence-on-earths-climate-123064">Climate explained: why carbon dioxide has such outsized influence on Earth's climate</a>
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<p>Nesquehonite occurs naturally when magnesian rocks slowly break down. It has been identified at the <a href="https://www.mindat.org/loc-266123.html">Paddy’s River mine</a> in the Australian Capital Territory and locations <a href="https://rruff.info/doclib/MinMag/Volume_34/34-268-370.pdf">in New South Wales</a>.</p>
<p>But scientists discovered it can also be <a href="https://www.frontiersin.org/articles/10.3389/fenrg.2016.00003/full">made</a> by passing carbon dioxide into an alkaline solution and having it react with magnesium chloride or sodium carbonate/bicarbonate. </p>
<p>This is a growing area of <a href="https://www.mdpi.com/2075-163X/7/9/172/htm">research</a>. </p>
<p>Other synthetic minerals such as hydrotalcite are produced when asbestos tailings passively absorb atmospheric carbon dioxide, as discovered by scientists at the <a href="https://www.sciencedaily.com/releases/2018/12/181212134430.htm">Woodsreef asbestos mine in New South Wales</a>. </p>
<p>You could say this is a kind of “modern-day alchemy” which, if taken advantage of, could be an effective way to suck carbon dioxide from the air at a large scale.</p>
<h2>Meeting society’s metal demands</h2>
<p>Mining and mineral processing is designed to recover metals from ore, which is a natural occurrence of rock or sediment containing sufficient minerals with economically important elements. But through mining and mineral processing, new minerals can also be created. </p>
<p>Smelting is used to produce a range of commodities such as lead, zinc and copper, by heating ore to high temperatures to produce pure metals. </p>
<p>The process also produces a glass-like waste product called slag, which is deposited as molten liquid, <a href="https://www.youtube.com/watch?v=T7kDNo3rIM4">resembling lava</a>.</p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/297051/original/file-20191015-98640-hlhncu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/297051/original/file-20191015-98640-hlhncu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/297051/original/file-20191015-98640-hlhncu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/297051/original/file-20191015-98640-hlhncu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/297051/original/file-20191015-98640-hlhncu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/297051/original/file-20191015-98640-hlhncu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/297051/original/file-20191015-98640-hlhncu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">This is a backscattered electron microscope image of historical slag collected from a Rio Tinto mine in Spain.</span>
<span class="attribution"><span class="source">Image collected by Anita Parbhakar-Fox at the University of Tasmania (UTAS)</span></span>
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<p>Once cooled, the textural and mineralogical similarities between lava and slag are crystal-clear. </p>
<p>Micro-scale inspection shows human-made minerals in slag have a unique ability to accommodate metals into their crystal lattice that would not be possible in nature.</p>
<p>This means metal recovery from mine waste (a potential secondary resource) could be an effective way to supplement society’s growing metal demands. The challenge lies in developing processes which are cost effective.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/wealth-in-waste-using-industrial-leftovers-to-offset-climate-emissions-49249">Wealth in waste? Using industrial leftovers to offset climate emissions</a>
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<h2>Ethically-sourced jewellery</h2>
<p>Our increasing knowledge on how to manufacture minerals may also have a major impact on the growing synthetic <a href="https://lightboxjewelry.com/">gem manufacturing industry</a>.</p>
<p>In 2010, the world was awestruck by the engagement ring given to Duchess of Cambridge Kate Middleton, valued at about <a href="https://news.thediamondstore.co.uk/facts-kate-middletons-engagement-ring/">£300,000</a> (AUD$558,429).</p>
<p>The ring has a 12-carat blue sapphire, surrounded by 14 solitaire diamonds, with a setting made from 18-carat white gold.</p>
<p>Replicas of it have been acquired by people across the globe, but for only a fraction of the price. How?</p>
<p>In 1837, Marc Antoine Gardin demonstrated that sapphires (mineralogically known as corundum or aluminium oxide) can be replicated by reacting metals with other substances such as chromium or boric acid. This produces a range of seemingly identical coloured stones. </p>
<p>On close examination, some properties may vary such as the presence of flaws and air bubbles and the stone’s hardness. But only a gemologist or gem enthusiast would likely notice this.</p>
<p>Diamonds can also be <a href="https://www.nytimes.com/2018/05/29/business/synthetic-diamond-production.html">synthetically made</a>, through either a high pressure, high temperature, or chemical vapour deposition process.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/297118/original/file-20191015-98648-x3d02t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/297118/original/file-20191015-98648-x3d02t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=466&fit=crop&dpr=1 600w, https://images.theconversation.com/files/297118/original/file-20191015-98648-x3d02t.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=466&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/297118/original/file-20191015-98648-x3d02t.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=466&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/297118/original/file-20191015-98648-x3d02t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=586&fit=crop&dpr=1 754w, https://images.theconversation.com/files/297118/original/file-20191015-98648-x3d02t.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=586&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/297118/original/file-20191015-98648-x3d02t.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=586&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Synthetic diamonds have essentially the same chemical composition, crystal structure and physical properties as natural diamonds.</span>
<span class="attribution"><span class="source">Instytut Fizyki Uniwersytet Kazimierza Wielkiego</span></span>
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<p>Creating synthetic gems is increasingly important as natural stones are becoming more difficult and expensive to source. In some countries, the rights of miners are also violated and this poses <a href="https://www.hrw.org/report/2018/02/08/hidden-cost-jewelry/human-rights-supply-chains-and-responsibility-jewelry">ethical concerns</a>. </p>
<h2>Medical and industrial applications</h2>
<p>Synthetic gems have industrial applications too. They can be used in window manufacturing, semi-conducting circuits and cutting tools. </p>
<p>One example of an entirely manufactured mineral is something called yttrium aluminum garnet (or YAG) which can be used as a <a href="https://www.sciencedirect.com/topics/medicine-and-dentistry/ndyag-laser">laser</a>.</p>
<p>In medicine, these lasers are used to correct glaucoma. In dental surgery, they allow soft gum and tissues to be cut away. </p>
<p>The move to develop new minerals will also support technologies enabling deep space exploration through the creation of <a href="https://narang.seas.harvard.edu/quantum-materials">‘quantum materials’</a>. </p>
<p>Quantum materials have unique properties and will help us create a new generation of electronic products, which could have a significant impact on space travel technologies. Maybe this will allow us to one day visit the birthplace of Edscottite?</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-quantum-materials-may-soon-make-star-trek-technology-reality-86378">How quantum materials may soon make Star Trek technology reality</a>
</strong>
</em>
</p>
<hr>
<p>In decades to come, the number of human-made minerals is <a href="http://blogs.discovermagazine.com/d-brief/2017/03/03/man-made-minerals-human-epoch/#.XaU045Mzai4">set to increase</a>. And as it does, so too does the opportunity to find new uses for them.</p>
<p>By expanding our ability to manufacture minerals, we could reduce pressure on existing resources and find new ways to tackle global challenges.</p><img src="https://counter.theconversation.com/content/123853/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>
Manufacturing minerals is an expanding field of study. Making more of them could help alleviate various pressures faced by our growing population. But how are they made, and where can they be used?
Anita Parbhakar-Fox, Senior Research Fellow in Geometallurgy/Applied Geochemistry, The University of Queensland
Paul Gow, Principal Research Fellow, The University of Queensland
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/115413
2019-04-17T16:43:02Z
2019-04-17T16:43:02Z
New CO₂ capture technology is not the magic bullet against climate change
<figure><img src="https://images.theconversation.com/files/269632/original/file-20190416-147499-2w6ers.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">If only it were that easy.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-illustration/man-turning-carbon-dioxide-knob-reduce-789727018?src=6QJ9fcxT_Y5HNi2fJohmCg-1-0">Olivier Le Moal/Shutterstock</a></span></figcaption></figure><p>According to a recent major UN <a href="https://theconversation.com/ipcc-1-5-report-heres-what-the-climate-science-says-104592">report</a>, if we are to limit temperature rise to 1.5 °C and prevent the most catastrophic effects of climate change, we need to reduce global CO₂ emissions to net zero by 2050. This means eliminating fossil fuel use fast – but to cushion that transition and offset the areas in which there is currently no replacement for combustibles, we need to actively remove CO₂ from the atmosphere. Planting trees and rewilding are a <a href="https://theconversation.com/george-monbiot-q-a-how-rejuvenating-nature-could-help-fight-climate-change-115313">large part</a> of this solution, but we are highly likely to need further technological assistance if we are to prevent climate breakdown. </p>
<p>So when recent news emerged that Canadian company Carbon Engineering has harnessed some well-known chemistry to capture CO₂ from the atmosphere at a cost of less than $100 a tonne, many media sources hailed the milestone as a <a href="https://www.bbc.co.uk/news/science-environment-47638586">magic bullet</a>. Unfortunately, the big picture isn’t as simple. Truly tipping the balance from carbon source to carbon sink is a delicate business, and our view is that the energy costs involved and likely downstream uses of captured CO₂ mean that Carbon Engineering’s “bullet” is anything but magic.</p>
<p>Given that CO₂ only accounts for 0.04% of the molecules in our air, capturing it might seem like a technological marvel. But chemists have been doing it on small scales since the 18th century, and it can even be done – albeit inefficiently – with supplies from the local hardware store.</p>
<p>As secondary school chemistry students will know, CO₂ reacts with limewater (calcium hydroxide solution) to give milky-white insoluble calcium carbonate. Other hydroxides capture CO₂ in the same way. Lithium hydroxide was the basis of the <a href="https://eic.rsc.org/feature/apollo-13--lithium-hydroxide-saves-the-day-/3007380.article">CO₂ absorbers</a> that kept the astronauts on Apollo 13 alive, and potassium hydroxide captures CO₂ so efficiently that it can be used to measure the carbon content of a combusted substance. The 19th-century apparatus used in this latter procedure still features on the American Chemical Society’s logo.</p>
<p>Unfortunately, this isn’t a small-scale problem anymore – we now need to capture billions of tonnes of CO₂, and fast.</p>
<p>Carbon Engineering’s technique is hydroxide chemistry at its best. At its pilot plant in British Columbia, air is pulled in by large fans and exposed to potassium hydroxide, with which CO₂ reacts to form soluble potassium carbonate. This solution is then combined with calcium hydroxide, producing solid and easily separable calcium carbonate, along with potassium hydroxide solution, which can be reused.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/269637/original/file-20190416-147502-rl2enj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/269637/original/file-20190416-147502-rl2enj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/269637/original/file-20190416-147502-rl2enj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/269637/original/file-20190416-147502-rl2enj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/269637/original/file-20190416-147502-rl2enj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/269637/original/file-20190416-147502-rl2enj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/269637/original/file-20190416-147502-rl2enj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Calcium carbonate can be used as a soil fertiliser.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/aerial-view-agriliming-activity-getting-limes-1343056742?src=l4b3nBjYRdWlrJjis84FfQ-1-1">Nordic Moonlight/Shutterstock</a></span>
</figcaption>
</figure>
<p>This part of the process costs relatively little energy and its product is essentially limestone – but making mountains of calcium carbonate doesn’t solve our problem. Though calcium carbonate has uses in agriculture and construction, this process would be far too expensive as a commercial source. It also isn’t a practical option for government-funded carbon storage due to the massive quantities of calcium hydroxide that would be required. To be feasible, direct air capture needs to produce concentrated CO₂ as its product, which can either be safely stored or put to use.</p>
<p>Thus, the solid calcium carbonate is heated to 900 °C to recover pure CO₂. This last step requires a vast amount of energy. In Carbon Engineering’s natural gas-fired plant, the whole cycle generates half a tonne of CO₂ for every tonne captured from air. The plant does capture this extra CO₂, and of course could be powered by renewable energy for a healthier carbon balance – but the problem of what to do with all the captured gas remains.</p>
<p>Swiss start-up company Climeworks is using similarly captured CO₂ to <a href="https://www.scientificamerican.com/article/ask-the-experts-does-rising-co2-benefit-plants1/">aid photosynthesis</a> and improve crop yield in nearby greenhouses, but as yet the price is nowhere near competitive. CO₂ can be sourced elsewhere for as little as one-tenth of Carbon Engineering’s $100 bottom line. There are also much cheaper ways for governments to offset emissions: it is far easier to capture CO₂ at the emission source, where the concentration is much higher. So this technology is likely to mainly interest high-emitting industries which may stand to benefit from CO₂ with green credentials. </p>
<p>For example, one of the key investors in Carbon Engineering’s capture technology is Occidental Petroleum, a major user of <a href="https://hub.globalccsinstitute.com/publications/what-happens-when-co2-stored-underground-qa-ieaghg-weyburn-midale-co2-monitoring-and-storage-project/8-what-co2-eor">Enhanced Oil Recovery</a> methods. In one such method, CO₂ is pumped into oil wells to increase the amount of crude oil that can be recovered, thanks to increased well pressure and/or improving the flow characteristics of the oil itself. However, including the energy cost of transporting and refining this extra oil, using the technology in this way will likely increase net emissions, not decrease them. </p>
<p>Another key spoke of Carbon Engineering’s operations is its <a href="https://carbonengineering.com/about-a2f/">Air To Fuels</a> technology, in which CO₂ is converted into combustible liquid fuel, ready to be burned again. Theoretically this provides a carbon-neutral fuel cycle, provided that each step of the process is powered with renewable energy. However, even this use is still a far cry from a negative emissions technology.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/m91P-R3kxOs?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Metal-organic frameworks are porous solids capable of capturing CO₂.</span></figcaption>
</figure>
<p>There are promising alternatives on the horizon. Metal-organic frameworks are sponge-like solids that squeeze the equivalent CO₂ surface area of a football pitch into the <a href="https://theconversation.com/mof-the-chart-why-a-record-breaking-surface-area-matters-9915">size of a sugar cube</a>. Using these surfaces for CO₂ capture requires far less energy – and companies have started exploring their commercial potential. However, large-scale production has not been perfected, and questions over their long-term stability for sustained CO₂ capture projects mean that their high cost is not yet merited.</p>
<p>With little chance that technologies still in the laboratory will be ready for gigatonne-scale capture within the next decade, the methods employed by Carbon Engineering and Climeworks are the best we currently have. But it’s important to remember that they’re nowhere near perfect. We will need to switch to more efficient methods of CO₂ capture as soon as we are able. As Carbon Engineering’s founder David Keith himself <a href="https://www.wired.com/story/the-potential-pitfalls-of-sucking-carbon-from-the-atmosphere/">points out</a>, carbon removal technologies are overhyped by policymakers, and have received “extraordinarily little” research funding thus far.</p>
<p>More generally, we must resist the temptation to see direct air capture as a magic bullet that saves us from having to address our carbon addiction. Reducing or neutralising the carbon burden in the life cycle of hydrocarbon fuels may be a step towards negative emissions technologies. But it is just that – a step. After being on the wrong side of the carbon ledger for so long, it’s past time to look beyond just breaking even.</p>
<hr>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/263883/original/file-20190314-28475-1mzxjur.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/263883/original/file-20190314-28475-1mzxjur.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=140&fit=crop&dpr=1 600w, https://images.theconversation.com/files/263883/original/file-20190314-28475-1mzxjur.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=140&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/263883/original/file-20190314-28475-1mzxjur.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=140&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/263883/original/file-20190314-28475-1mzxjur.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=176&fit=crop&dpr=1 754w, https://images.theconversation.com/files/263883/original/file-20190314-28475-1mzxjur.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=176&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/263883/original/file-20190314-28475-1mzxjur.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=176&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
</figcaption>
</figure>
<p><em><a href="https://theconversation.com/imagine-newsletter-researchers-think-of-a-world-with-climate-action-113443?utm_source=TCUK&utm_medium=linkback&utm_campaign=TCUKengagement&utm_content=Imagineheader1115413">Click here to subscribe to our climate action newsletter. Climate change is inevitable. Our response to it isn’t.</a></em></p><img src="https://counter.theconversation.com/content/115413/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Chris Hawes receives funding from the Royal Society, and has previously received funding from the Royal Society of Chemistry</span></em></p>
Carbon Engineering’s clever harnessing of high-school chemistry is just a small step on the path to negative emissions.
Chris Hawes, Lecturer in Inorganic Chemistry, Keele University
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/93174
2019-03-12T10:45:49Z
2019-03-12T10:45:49Z
Can we tweak marine chemistry to help stave off climate change?
<figure><img src="https://images.theconversation.com/files/262729/original/file-20190307-82684-29h2rv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Trapping carbon dioxide in minerals happens naturally over thousands of years. Can humans speed it up – safely?</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/39551170@N02/16100332997/in/photolist-4Xk3S-7wWH3S-7wWMyN-8pNMsR-qwJq5e-ffoV2v-aufcps-6EXnYQ-6EXono-pz72is-4Hc8wn-oUDBA1-9rYHc9-5xZ3Aw-8QBHsw-8QBLGL-7wT1hD-e1dKi6-8QBLXE-8QyF58-7XE3sq-eTzCto-8QyFbH-SYkS8H-LFPKfK-d1npTY-d1npxA-d1njeY-d1njr9-d1njLy-ne5tK-d1nqcw-d1nc7J-d1nr6b-d1nmbL-TeVuF1-d1n8rq-d1nhKy-2arEo4t-Cof1ds-d1niT7-d1n859-VWBXDw-d1ny81-5Kjdev-d1npHS-d1nxSh-d1njXC-A5tBN3-d1niqS">Simon Clancy</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>The world’s nations are nowhere near to meeting the global Paris Agreement’s goals on climate change of holding global temperature increases to <a href="https://theconversation.com/why-is-climate-changes-2-degrees-celsius-of-warming-limit-so-important-82058">2 degrees Celsius</a> compared to 19th-century averages, much less its more aspirational goal of holding temperatures to a <a href="https://www.ipcc.ch/sr15/chapter/summary-for-policy-makers/">1.5°C rise</a>.</p>
<p>The most recent <a href="https://www.unenvironment.org/resources/emissions-gap-report-2018">Emissions Gap Report</a> from the United Nations Environment Program notes “global greenhouse gas emissions show no signs of peaking.” According to <a href="https://www.nature.com/articles/nclimate3352">another study</a>, the chance that humans can limit warming to no more than 2°C by 2100 is no more than 5 percent, and it’s likely that temperatures will rise somewhere between 2.6°-3.7°C by the end of the century.</p>
<p>These foreboding trends have led to an increasing focus on ways to remove carbon dioxide from the atmosphere. Among the methods being explored is the use of the ocean to absorb and/or store carbon by adding crushed rocks or other sources of alkalinity to react with CO2 in seawater, ultimately consuming atmospheric CO2. </p>
<p>Could this type of large-scale carbon dioxide removal work? A closer look illustrates the potential environmental trade-offs of deploying marine carbon dioxide removal and the complex technical, economic and international governance issues it raises.</p>
<h2>Land versus ocean carbon capture and storage</h2>
<p><a href="https://www.youtube.com/watch?v=LEmjD1ylEdo">We</a> <a href="https://www.researchgate.net/publication/320966732_Geoengineering_the_oceans_an_emerging_frontier_in_international_climate_change_governance">and</a> <a href="https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1002/2016RG000533">other</a> <a href="https://www.nextbigfuture.com/2018/07/restore-the-oceans-and-get-up-to-50-times-the-fish-and-store-a-trillion-tons-of-co2.html">researchers</a> see the ocean as a logical place to look for additional carbon dioxide removal opportunities since it currently passively absorbs about 10 gigatons (10,000,000,000 tons) of CO2 per year or about <a href="https://www.wri.org/blog/2018/12/new-global-co2-emissions-numbers-are-they-re-not-good">one-quarter of the world’s annual emissions</a>. In addition, the oceans contain vastly more carbon than the atmosphere, soils, plants and animals combined, and may have the potential to store <a href="https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1002/2016RG000533">trillions of tons more</a>.</p>
<p>The latest report from the Intergovernmental Panel on Climate Change focused heavily on land-based methods for carbon capture and storage. One prominent technique is called bioenergy with carbon capture and storage, <a href="https://www.sciencedirect.com/science/article/pii/S2214629618302998">BECCS</a>, where plant biomass would be burned to produce usable energy and the resulting CO2 is pumped underground.</p>
<p>However, there are a number of concerns about the <a href="https://theconversation.com/why-we-cant-reverse-climate-change-with-negative-emissions-technologies-103504">potential negative impacts</a> of large-scale deployment of BECCS and other land-plant-based methods, notably the worry that huge amounts of agricultural land would be diverted to grow dedicated crops. This could reduce access of <a href="https://link.springer.com/article/10.1007/s13412-017-0445-6">low-income populations to food</a>, place demands on <a href="https://fern.org/sites/default/files/news-pdf/Fern%20BECCS%20briefing_0.pdf">water</a> and have serious negative impacts on biodiversity due to <a href="https://www.carbonbrief.org/geoengineering-carries-large-risks-for-natural-world-studies-show">ecosystem disruption</a>. </p>
<h2>Speeding up geochemistry</h2>
<p>Perhaps the best-known – and at times, <a href="https://www.scientificamerican.com/article/iron-dumping-ocean-experiment-sparks-controversy">controversial</a> – method for marine carbon dioxide removal is <a href="https://www.frontiersin.org/articles/10.3389/fmars.2018.00337/full">stimulating photosynthesis</a> to increase CO2 absorption. For example, in regions where marine plant growth is limited by iron, this element can be <a href="http://oceaneos.org/ocean-seeding/what-is-ocean-seeding/">added</a> to enhance CO2 uptake and carbon storage where at least some of the biomass carbon formed eventually sinks to and is buried in the ocean floor. Other approaches include restoring, adding or culturing marine plants or microbes, such as <a href="https://oceanservice.noaa.gov/facts/bluecarbon.html">Blue Carbon</a>. </p>
<p>Another technique being considered is to try to <a href="https://doi.org/10.1016/j.apgeochem.2017.11.001">accelerate the chemical reaction of CO2 with common rock minerals</a>, a natural process known as <a href="http://www.columbia.edu/%7Evjd1/weathering.htm">mineral weathering</a>. When rain reacts with alkaline rocks and CO2, there’s a chemical reaction, which can be catalyzed by biological activity in soils, that converts the CO2 to dissolved mineral bicarbonate and carbonate ions which then typically run off into the ocean. Mineral weathering plays a major role in removing excess atmospheric CO2, but only on <a href="http://climatemodels.uchicago.edu/geocarb/archer.2009.ann_rev_tail.pdf">geologic time scales</a> – 100,000 years or more. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/262512/original/file-20190306-100802-1hdpj42.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/262512/original/file-20190306-100802-1hdpj42.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/262512/original/file-20190306-100802-1hdpj42.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/262512/original/file-20190306-100802-1hdpj42.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/262512/original/file-20190306-100802-1hdpj42.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/262512/original/file-20190306-100802-1hdpj42.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/262512/original/file-20190306-100802-1hdpj42.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/262512/original/file-20190306-100802-1hdpj42.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The natural process of mineral weathering starts with rain which absorbs carbon dioxide from the air and then reacts with rock and biota in soils, forming dissolved mineral bicarbonate and a much smaller quantity of carbonate ions. These then run off into the ocean where the carbon is stored in these forms for many millennia before precipitating to the ocean floor as carbonate minerals. The idea of enhanced weathering is to greatly speed up this process by adding crushed rocks or other sources of alkalinity to react with CO2 in seawater, ultimately consuming atmospheric CO2 and adding it as dissolved mineral bicarbonate and carbonate to the already very large reservoir of these compounds in the ocean.</span>
<span class="attribution"><span class="source">Greg Rau</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Various <a href="https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1002/2016RG000533">ways to accelerate mineral weathering and ocean carbon storage</a> that have been proposed include adding to surface waters finely ground alkaline minerals or adding common, industrially produced alkaline chemicals, such as quicklime (CaO), calcium hydroxide (Ca(OH)2), and lye or caustic soda (NaOH). Once added to the ocean, these compounds react with excess CO2 in seawater and air, principally forming stable, dissolved mineral bicarbonate, thus removing and sequestering CO2. </p>
<p>Such ocean alkalization could be achieved via distribution from shore or by ships. Another proposal is to manufacture alkalinity at sea using local marine energy sources: <a href="https://www.sciencedirect.com/science/article/pii/S136403211830532X">for example</a>, employing electricity derived from the ocean’s very significant vertical temperature gradient. Reacting waste CO2 with minerals on shore and then pumping the resulting dissolved alkaline material into the ocean is also an <a href="https://pubs.acs.org/doi/abs/10.1021/es102671x">option</a>. All of the preceding would simply add to the already vast bicarbonate and carbonate reservoir in the ocean. </p>
<p>An additional benefit of ocean alkalization is that it also helps counter ocean acidification, the “<a href="https://www.nrdc.org/sites/default/files/NRDC-OceanAcidFSWeb.pdf">other CO2 problem</a>” stemming from the ocean’s absorption of excess CO2 from the air. Acidification can interfere with the ability of calcifying organisms, such as oysters, clams and corals to construct their skeletons or shells, as well as impact other pH-sensitive marine biogeochemical processes. </p>
<h2>What we don’t know</h2>
<p>The actual practical capacity of ocean alkalization to counter climate change and acidification <a href="https://core.ac.uk/download/pdf/42964576.pdf">remains uncertain</a>. </p>
<p>Considering the logistics, cost and impacts of extracting or manufacturing alkalinity and dispersing it, studies have estimate that <a href="https://www.atmos-chem-phys.net/9/5539/2009/acp-9-5539-2009.pdf">air CO2 drawdowns</a> of perhaps 30 parts per million or less might be realistic. This would be helpful given that the level of CO2 in preindustrial times was <a href="https://link.springer.com/article/10.1007%2FBF02423528">260-270 parts per million</a> and is now 410 parts per million.</p>
<p>We calculate a global drawdown of atmospheric CO2 by 30 parts per million would require near-zero emissions from human activities, plus the removal and storage of some 470 gigatons of CO2. To achieve this, a minimum of roughly 500 gigatons of rock would need to be used to generate the required alkalinity. Current global rock extraction is on the order of <a href="https://www.nature.com/articles/s41477-018-0108-y">50 gigatons per year</a>, so holding other rock uses steady while increasing this extraction rate by 50 percent could theoretically allow us to achieve the drawdown in 20 years. This obviously needs to be tested at vastly smaller scales to determine what global capacity and rates might be realizable.</p>
<p>Nor is this just a matter of alkalinity production; there are potential negative impact of <a href="https://www.frontiersin.org/articles/10.3389/fmars.2018.00337/full">ocean alkalization on marine ecosystems</a> that need to be considered. In addition to the <a href="https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1002/2016RG000533">effects</a> of pH and alkainity elevation (either instantaneous or gradual), alkalinity addition would likely carry with it other elements or compounds, such as trace metals and silica, that can also affect marine biogeochemistry. Little research has been conducted on these points, but the <a href="https://www.nature.com/articles/nature17155">results so far</a> generally find no or positive effects on marine life. Further investigation is needed to fully understand the environmental and ecological consequences, including conducting small and medium-sized field trials. </p>
<p>Any deployment would need to be subjected to strict monitoring requirements to assess both the environmental benefits and well as the negative impacts of large scale deployment. Some measure of confidence in the use of ocean alkalization might be found in the fact that natural mineral weathering and alkalinity delivery to the ocean has naturally occurred for billions of years (currently at the rate of about 1 gigaton of CO2 consumed and stored per year), apparently with the marine ecosystem well adapted to if not requiring this input. Nevertheless, the possibility of significantly and safely scaling up this natural process requires further research. </p>
<h2>Legal questions</h2>
<p>At a legal level, countries would need to address international governance issues associated with this approach. Presumably, the Paris Agreement would be one of the regimes involved given its focus on addressing climate change. Any role ocean akalinity could play in countries’ pledges to mitigate emissions would require provisions that mandate assessment of potential impacts of deployment. The Paris Agreement could facilitate this given its references in various provisions to the need to assess the impacts of response measures in the context of ecosystems, sustainability, development and human rights.</p>
<p>Ocean-focused regimes such as the Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter and the <a href="http://www.imo.org/en/OurWork/Environment/LCLP/Documents/LC1972.pdf">Law of the Sea Convention</a>, and its <a href="http://www.imo.org/en/OurWork/Environment/LCLP/Documents/PROTOCOLAmended2006.pdf">Protocol</a>, might also seek to be engaged in assessment and regulation, as well as the <a href="https://www.cbd.int/convention/text/">Convention on Biological Diversity</a>. Coordinating the potential interventions of all of these regimes’ responses would be another challenge posed by deployment of ocean alkalinity, as would the many other carbon dioxide removal approaches that could have transboundary impacts.</p>
<p>The specter of potentially catastrophic climate change by the end of the century has stimulated interest in an array of new technological options to remove CO2 from the ocean and atmosphere at large scale. But they could also pose risks of their own. Adding alkaline materials to speed up mineral weathering is one such approach that deserves serious consideration, though only after thorough scrutiny.</p><img src="https://counter.theconversation.com/content/93174/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Greg H Rau received funding from the Department of Energy, Lawrence Livermore National Laboratory, National Science Foundation, NOAA and the Department of the Interior.</span></em></p><p class="fine-print"><em><span>Wil Burns does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>
Adding industrial chemicals and natural alkaline minerals could slow climate change, but like other geoengineering proposals, it comes with many complex technical and legal challenges.
Wil Burns, Professor of Research & Co-Director, Institute for Carbon Removal Law & Policy, American University School of International Service
Greg H. Rau, Senior Research Scientist, University of California, Santa Cruz
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/108041
2018-12-05T18:56:59Z
2018-12-05T18:56:59Z
Carbon emissions will reach 37 billion tonnes in 2018, a record high
<p>Carbon dioxide (CO₂) emissions from fossil fuels and industry are projected to rise more than 2% (range 1.8% to 3.7%) in 2018, taking global fossil CO₂ emissions to a new record high of 37.1 billion tonnes. </p>
<p>The strong growth is the second consecutive year of increasing emissions since the 2014-16 period when emissions stabilised, further slowing progress towards the goals of the Paris Agreement that require a peak in greenhouse gas emissions as soon as possible. Strong growth in emissions from the use of coal, oil and natural gas suggests CO₂ emissions are likely to increase further in 2019.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/what-is-a-pre-industrial-climate-and-why-does-it-matter-78601">What is a pre-industrial climate and why does it matter?</a>
</strong>
</em>
</p>
<hr>
<p>Strong energy demand is behind the rise in emissions growth, which is outpacing the speed at which decarbonisation of the energy system is taking place. Total energy consumption around the world increased by one sixth over the past decade, the result of a growing global middle class and the need to provide electricity to hundreds of millions of people living in poverty. The challenge, then, is for all nations to decarbonise their economies while also satisfying the need for energy, particularly in developing countries where continued growth in energy supply is needed.</p>
<p>These analyses are part of the new annual assessment of the Global Carbon Project (<a href="http://www.globalcarbonproject.org/index.htm">GCP</a>), published today in <a href="https://www.earth-syst-sci-data.net/10/2141/2018/">three</a> <a href="http://iopscience.iop.org/article/10.1088/1748-9326/aaf303/meta">separate</a> <a href="https://www.nature.com/articles/d41586-018-07585-6">papers</a>. The GCP brings together scientists who use climate and industrial data from around the world to develop the most comprehensive picture of the Earth’s sources and sinks of greenhouse gases.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/248481/original/file-20181203-194925-1wdjier.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/248481/original/file-20181203-194925-1wdjier.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/248481/original/file-20181203-194925-1wdjier.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/248481/original/file-20181203-194925-1wdjier.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/248481/original/file-20181203-194925-1wdjier.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/248481/original/file-20181203-194925-1wdjier.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/248481/original/file-20181203-194925-1wdjier.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/248481/original/file-20181203-194925-1wdjier.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Historical CO₂ fossil fuel emissions (black, red dot is our projection for 2018) and the Shared Socioeconomic Pathways (SSPs) from the IPCC 1.5°C special report (2018) to stabilise the climate below 1.5°C and 2°C warming above pre-industrial levels.</span>
<span class="attribution"><span class="source">Global Carbon Project/Jackson et al. 2018</span></span>
</figcaption>
</figure>
<h2>Sources of fossil fuel emissions</h2>
<p>A surprise in 2018 (and 2017) was the return to growth in CO₂ emissions from coal use after an apparent peak in 2013, although coal emissions in 2017 were still 3% below the 2013 record high. This change was one primary reason for the higher increase in emissions growth in 2018, on top of long-term growth in oil and natural gas emissions. The largest national contributions to the growth in coal emissions came from China and India, while the single largest decline in coal emissions was in the United States, where more than 250 coal-fired power plants have closed since 2010 and <a href="https://platform.mi.spglobal.com/web/client?auth=inherit#news/article?id=48671375&cdid=A-48671375-11561&utm_content=bufferd8095&utm_medium=social&utm_source=twitter.com&utm_campaign=buffer">more are expected</a> to close down over the next five years.</p>
<p>The growth of emissions from cement production has slowed significantly.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/248340/original/file-20181203-194941-1txzrqg.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/248340/original/file-20181203-194941-1txzrqg.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/248340/original/file-20181203-194941-1txzrqg.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/248340/original/file-20181203-194941-1txzrqg.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/248340/original/file-20181203-194941-1txzrqg.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/248340/original/file-20181203-194941-1txzrqg.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/248340/original/file-20181203-194941-1txzrqg.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/248340/original/file-20181203-194941-1txzrqg.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Annual global CO₂ fossil fuel emissions to 2017, with the 2018 projection suggesting coal will approach the levels seen in 2013. (Le Quere et al. 2018, ESSD; Jackson et al. 2018, ERL)</span>
<span class="attribution"><span class="source">Global Carbon Project</span></span>
</figcaption>
</figure>
<h2>Country trends</h2>
<p>Most countries are contributing to the increase in global fossil CO₂ emissions. However, 19 countries representing 20% of the global emissions, showed declining trends in emissions in the past decade (2008-17) while their economies continued to grow. These countries are: Aruba, Barbados, Czech Republic, Denmark, France, Greenland, Iceland, Ireland, Malta, the Netherlands, Romania, Slovakia, Slovenia, Sweden, Switzerland, Trinidad and Tobago, the UK, the US, and Uzbekistan.</p>
<p>Turning to changes in CO₂ emissions in 2018, unexpectedly, China, which accounts for 27% of global emissions, is set to grow 4.7%, up from 1.7% growth in 2017. Likewise, and despite the long-term trend of emissions declines, the US is set to increase its emissions by 2.5% this year, due to increased heating and cooling demands and oil use. The European Union is set to reduce its emissions by 0.7%, compared with 1.4% growth in 2017, potentially the first reduction since 2014. Indian emissions are expected to grow 6.3% on the back of strong growth in coal use. Greenhouse gas emissions in Australia have increased for the last four years to <a href="http://www.environment.gov.au/climate-change/climate-science-data/greenhouse-gas-measurement/publications/quarterly-update-australias-national-greenhouse-gas-inventory-june-2018">June 2018</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/248341/original/file-20181203-194938-1qrbjwi.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/248341/original/file-20181203-194938-1qrbjwi.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/248341/original/file-20181203-194938-1qrbjwi.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/248341/original/file-20181203-194938-1qrbjwi.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/248341/original/file-20181203-194938-1qrbjwi.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/248341/original/file-20181203-194938-1qrbjwi.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/248341/original/file-20181203-194938-1qrbjwi.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/248341/original/file-20181203-194938-1qrbjwi.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Annual CO₂ fossil fuel emissions to 2017, and projected 2018 emissions based on partial data to September (dot points with error bars).</span>
<span class="attribution"><span class="source">Global Carbon Project/Le Quere et al. 2018/Jackson et al. 2018</span></span>
</figcaption>
</figure>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/248344/original/file-20181203-194935-1an1pod.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/248344/original/file-20181203-194935-1an1pod.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/248344/original/file-20181203-194935-1an1pod.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=329&fit=crop&dpr=1 600w, https://images.theconversation.com/files/248344/original/file-20181203-194935-1an1pod.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=329&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/248344/original/file-20181203-194935-1an1pod.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=329&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/248344/original/file-20181203-194935-1an1pod.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=414&fit=crop&dpr=1 754w, https://images.theconversation.com/files/248344/original/file-20181203-194935-1an1pod.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=414&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/248344/original/file-20181203-194935-1an1pod.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=414&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">CO₂ emissions per capita to 2017. Global Carbon Project 2018. Access the complete infographic at: http://www.globalcarbonproject.org/carbonbudget/17/infographics.</span>
</figcaption>
</figure>
<h2>Outlook</h2>
<p>An unprecedented energy revolution is already underway towards cleaner sources of energy. Globally, renewable energy (solar, wind, and biofuels) is growing at an extraordinary rate, with a doubling of the global capacity every four years, albeit starting from a very low base compared with energy generated from fossil fuels.
A continuation and acceleration of this trend is <a href="https://www.nature.com/articles/nclimate3202">consistent</a> with the requirements of the Paris Agreement. However, the same scenarios also call for the equally rapid decline in emissions from fossil fuels, something we do not see in our latest data presented here. The stronger growth in emissions projected for 2018, which is likely to extend into 2019, is inconsistent with agreed-upon climate targets. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/248343/original/file-20181203-194953-1edkrcs.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/248343/original/file-20181203-194953-1edkrcs.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/248343/original/file-20181203-194953-1edkrcs.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/248343/original/file-20181203-194953-1edkrcs.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/248343/original/file-20181203-194953-1edkrcs.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/248343/original/file-20181203-194953-1edkrcs.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/248343/original/file-20181203-194953-1edkrcs.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/248343/original/file-20181203-194953-1edkrcs.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption"></span>
<span class="attribution"><span class="source">Global Carbon Project</span></span>
</figcaption>
</figure>
<p>The recent <a href="https://www.unenvironment.org/resources/emissions-gap-report-2018">Emissions Gap Report 2018 </a>shows large and growing discrepancies among 1) current emissions trends, 2) national emissions reduction committed by countries, and 3) the declining trends required to meet the targets of the Paris agreement.</p>
<p>All countries need to increase their mitigation efforts and levels of ambition to reverse the tide of emissions growth, if decarbonisation pathways consistent with the climate targets of <a href="https://www.ipcc.ch/report/sr15/">1.5°C</a> and <a href="https://www.ipcc.ch/report/ar5/">well-below 2°C</a> are to be met.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/weve-got-a-climate-goal-of-1-5-degrees-so-how-do-we-get-there-52413">We've got a climate goal of 1.5 degrees – so how do we get there?</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/108041/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Pep Canadell receives funding from the Australian National Environmental Science Program - Earth Systems and Climate Change Hub</span></em></p><p class="fine-print"><em><span>Corinne Le Quéré is affiliated with the UK Committee on Climate Change and the French Haut-Conseil pour l'action climatique. </span></em></p><p class="fine-print"><em><span>Glen Peters receives funding from the Research Council of Norway and the European Commission (Horizon 2020). </span></em></p><p class="fine-print"><em><span>Robbie Andrew receives funding from the Research Council of Norway. </span></em></p><p class="fine-print"><em><span>Rob Jackson receives funding from the Gordon and Betty Moore Foundation. </span></em></p>
For the second year in a row global greenhouse emissions from fossil fuels have risen, putting 2018 on course to set a new record, according to an annual audit from the Global Carbon Project.
Pep Canadell, CSIRO Scientist, and Executive Director of the Global Carbon Project, CSIRO
Corinne Le Quéré, Professor, Tyndall Centre for Climate Change Research, University of East Anglia
Glen Peters, Research Director, Center for International Climate and Environment Research - Oslo
Robbie Andrew, Senior Researcher, Center for International Climate and Environment Research - Oslo
Rob Jackson, Chair, Department of Earth System Science, and Chair of the Global Carbon Project, globalcarbonproject.org, Stanford University
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/99255
2018-07-03T14:58:53Z
2018-07-03T14:58:53Z
CO₂ shortage: why can’t we just pull carbon dioxide out of the air?
<figure><img src="https://images.theconversation.com/files/225926/original/file-20180703-116126-12s06ez.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/high-pollution-coal-power-plant-133957013">Shutterstock</a></span></figcaption></figure><p>More people than ever are acutely aware that rising levels of carbon dioxide (CO₂) in the atmosphere are accelerating climate change and global warming. And yet food manufacturers have been issuing stark warnings that they’ve nearly run out of the gas, which is used in many products from <a href="http://time.com/5328059/carbon-dioxide-co2-beer-crumpet-shortage/">beer to crumpets</a>. The obvious question is: why we can’t just capture the excess CO₂ from the atmosphere and use that?</p>
<p>It is actually possible to take CO₂ from the atmosphere using a process known as direct air capture. Indeed, there are a number of companies across the world, including <a href="http://www.climeworks.com/">one in Switzerland</a> and <a href="http://carbonengineering.com/">another in Canada</a>, that can <a href="http://www.bbc.co.uk/news/science-environment-44396781">already carry out this process</a>. In theory, it could turn a problem into a valuable resource, particularly in developing countries with little other natural wealth.</p>
<p>The problem is the cost. While the amount of CO₂ in the air is damaging the climate, relatively speaking there are so few CO₂ molecules in the air that sucking them out is very expensive. But there may be other solutions that could help reduce carbon emissions and provide a new source of CO₂ for industry.</p>
<p>It’s all a matter of concentration and energy consumption. The amount of CO₂ in the air (which is mostly made up of nitrogen and oxygen) is around <a href="https://www.esrl.noaa.gov/gmd/aggi/aggi.html">400 parts per million</a> or 0.04%. If we were to represent a sample of molecules from the air as a bag of 5,000 balls, just two of them would be CO₂. Pulling them out of the bag would be very difficult.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/225783/original/file-20180702-116123-q1huss.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/225783/original/file-20180702-116123-q1huss.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=459&fit=crop&dpr=1 600w, https://images.theconversation.com/files/225783/original/file-20180702-116123-q1huss.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=459&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/225783/original/file-20180702-116123-q1huss.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=459&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/225783/original/file-20180702-116123-q1huss.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=577&fit=crop&dpr=1 754w, https://images.theconversation.com/files/225783/original/file-20180702-116123-q1huss.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=577&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/225783/original/file-20180702-116123-q1huss.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=577&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Like finding a ball in a bag.</span>
<span class="attribution"><span class="source">Peter Styring</span>, <span class="license">Author provided</span></span>
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<p>We can capture CO₂ using what’s known as a sorbent material that either physically interacts or bonds with the gas at a molecular level. To capture a viable amount of CO₂ from the air, we would need to compress huge amounts in order to pass it through the sorbent, something that would require a lot of energy.</p>
<p>The exhaust of power stations is a more concentrated source of CO₂ (and one responsible for so much of our total carbon emissions). The Carbon XPRIZE, a competition to encourage the development of carbon capture and utilisation technology, has identified <a href="https://carbon.xprize.org/teams">ten finalists</a> that focus on capturing CO₂ from power plants rather than the atmosphere.</p>
<p>Yet while the typical CO₂ concentration of <a href="https://chemengineering.wikispaces.com/Flue+gas">around 10%</a> (600 balls out of the 5,000) in power station exhaust is much greater than that of air, capturing the CO₂ would still be a costly way of purifying the gas using current technologies. You also need to remove the water vapour in the exhaust, which would require <a href="http://electricheatingcosts.com/dehumidifier-running-costs/">more energy</a>.</p>
<h2>Better sources</h2>
<p>As it becomes more important to reduce the concentration of CO₂ in the atmosphere, or if you needed to produce the gas in remote locations with large renewable energy sources, direct air capture could become a viable technology. But at the moment there are CO₂ sources that are more concentrated and so <a href="http://pubs.rsc.org/en/content/articlelanding/2016/fd/c6fd00035e#!divAbstract">cheaper to harness</a>. </p>
<p>For example, distilleries and breweries produce the gas as a waste product with high purity (over 99.5%) once any water has been removed. Cement works, steel works and other process industries also have relatively high <a href="https://www.gov.uk/government/collections/uk-greenhouse-gas-emissions-statistics">CO₂ concentrations</a>. Building smaller facilities that just capture the CO₂ from individual factories and plants would be a cheaper way to create a new source of the gas. They may also prove a good investment at plants that need their own supply of CO₂ to carry out their processes.</p>
<p>The current CO₂ shortage is mainly affecting the food and drink industry. But we’re also starting to see a greater push to use CO₂ in other industries as a way of creating a market for a substance that is otherwise a waste product contributing to dangerous climate change. You can now buy chemicals and building materials that started life as CO₂ molecules instead of fossil fuels, for example, including mineral aggregates that actually capture more carbon than is <a href="http://c8a.co.uk/">used to produce them</a>.</p>
<p>As more of these CO₂ utilisation technologies emerge, demand for the gas will increase and so will the need for more localised production. The future is about turning a waste into a commodity.</p><img src="https://counter.theconversation.com/content/99255/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Peter Styring receives funding from UKRI, Horizon 2020 and the Global CO2 Initiative. He is affiliated with the Liberal Democratic Party as a Member. </span></em></p><p class="fine-print"><em><span>Katy Armstrong receives funding fromthe EPSRC, Horizon 2020 and the Global CO2 Initiative.</span></em></p>
Technology exists to capture carbon dioxide from the atmosphere but it has a big cost.
Peter Styring, Professor of Chemical Engineering and Chemistry, University of Sheffield
Katy Armstrong, CO2Chem Network Manager, University of Sheffield
Licensed as Creative Commons – attribution, no derivatives.