tag:theconversation.com,2011:/au/topics/arctic-ice-7694/articlesArctic ice – The Conversation2023-06-23T15:51:06Ztag:theconversation.com,2011:article/2077852023-06-23T15:51:06Z2023-06-23T15:51:06ZThe melting Arctic is a crime scene. The microbes I study have long warned us of this catastrophe – but they are also driving it<p>The Arctic’s climate is warming at least four times faster than the global average, causing irrevocable changes to this vast <a href="https://news.sky.com/story/dramatic-changes-to-polar-ice-caps-revealed-on-new-map-of-arctic-and-antarctica-12898550">landscape</a> and precarious <a href="https://www.nwf.org/Educational-Resources/Wildlife-Guide/Wild-Places/Arctic#:%7E:text=The%20Arctic%20is%20a%20unique,in%20the%20summer%20to%20breed.">ecosystem</a> – from the anticipated <a href="https://earth.org/polar-bears-to-become-extinct-by-2100/">extinction of polar bears</a> to the <a href="https://www.scientificamerican.com/article/as-arctic-sea-ice-melts-killer-whales-are-moving-in/#:%7E:text=Killer%20whales%20often%20feed%20on,navigate%20through%20the%20icy%20waters.">appearance of killer whales</a> in ever-greater numbers. A new <a href="https://www.nature.com/articles/s41467-023-38511-8">study</a> suggests the Arctic Ocean could be ice-free in summer <a href="https://theconversation.com/arctic-ocean-could-be-ice-free-in-summer-by-2030s-say-scientists-this-would-have-global-damaging-and-dangerous-consequences-206974">as soon as the 2030s</a> – around a decade earlier than previously predicted.</p>
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<span class="caption">A new Arctic sea ice map compares the 30-year average with recent ten-year averages.</span>
<span class="attribution"><a class="source" href="https://www.bas.ac.uk/media-post/new-map-of-polar-regions-updated-to-reflect-ice-loss-name-changes-and-new-data/">British Antarctic Survey</a></span>
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<p>But to properly understand the pace and force of what’s to come, we should instead focus on organisms too small to be seen with the naked eye. These single-celled microbes are both the watchkeepers and arch-agitators of the Arctic’s demise.</p>
<p>Scientists like me who study them have become forensic pathologists, processing crime scenes in our Arctic field sites. We don the same white anti-contamination suits, photograph each sampling site, and bag our samples for DNA analysis. In some areas, red-coloured microbes even create an effect known as “blood snow”.</p>
<p>In this complex criminal investigation, however, the invisible witnesses are also responsible for the damage being done. Microbes testify to the vulnerability of their Arctic habitats to the changes that humans have caused. But they also create powerful climate feedback loops that are doing ever-more damage both to the Arctic, and the planet as a whole.</p>
<h2>Zipping headlong into icy oblivion</h2>
<p>My first visit to the Arctic was also nearly my last. As a PhD student in my early 20s in 2006, I had set out with colleagues to sample microbes growing on a glacier in the Norwegian archipelago of <a href="https://www.theguardian.com/environment/2023/may/13/svalbard-the-arctic-islands-where-we-can-see-the-future-of-global-heating">Svalbard</a> – the planet’s northernmost year-round settlement, about 760 miles from the North Pole.</p>
<p>Our treacherous commute took us high above the glacier, traversing an icy scree slope to approach its flank before crossing a river at the ice’s margin. It was a route we had navigated recently – yet this day I mis-stepped. Time slowed as I slid towards the stream swollen with ice melt, my axe bouncing uselessly off the glassy ice. I was zipping headlong into icy oblivion.</p>
<p>In that near-death calm, two things bothered me. The water would carry me deep into the glacier, so it would be decades before my remains were returned to my family. And the ear-worm of that field season meant I would die to the theme tune to Indiana Jones.</p>
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<p><strong><em>This article is part of Conversation Insights</em></strong>
<br><em>The Insights team generates <a href="https://theconversation.com/uk/topics/insights-series-71218">long-form journalism</a> derived from interdisciplinary research. The team is working with academics from different backgrounds who have been engaged in projects aimed at tackling societal and scientific challenges.</em></p>
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<p>Thankfully, the scree slowed my slide – I lived and learned, quickly, that dead scientists don’t get to write up their papers. And I’m still learning about the tiny organisms that populate every habitat there: from seawater in the Arctic Ocean to ice crystals buried deep in the <a href="https://en.wikipedia.org/wiki/Greenland_ice_sheet">Greenland ice sheet</a>.</p>
<p>These micro-managers of all manner of planetary processes are acutely sensitive to the temperatures of their habitats. The slightest change above freezing can transform an Arctic landscape from a frozen waste devoid of liquid water to one where microbes get busy reproducing in nutrient-rich water, transforming themselves in ways that <a href="https://www.nature.com/articles/ismej2010108">further amplify</a> the effects of climate warming.</p>
<p>The Svalbard region is now warming seven times faster than the global average. While much of the world continues its efforts to limit global warming to 1.5°C above pre-industrial levels, in the Arctic, that battle was lost long ago.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/0VOGGdeB8eI?wmode=transparent&start=17" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Joseph Cook’s film on the microbes that inhabit the Greenland ice sheet.</span></figcaption>
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<h2>Decades ahead of us all</h2>
<p>It’s 2011, and <a href="http://www.earth.s.chiba-u.ac.jp/english/education/education02/staff16.html">Nozomu Takeuchi</a> is visiting Svalbard from Japan. It has been a difficult year back home, following the earthquake, tsunami and Fukushima nuclear incident, but Nozomu – a glacier ecologist and professor at Chiba University – is unrelenting in his quest to measure the effects of climate change. </p>
<p>Just hours after he stepped off a plane in the August midnight sun at Longyearbyen airport, we are marching up the nearest glacier. Above us, snow-capped mountain sides loom out of the swirling mist.</p>
<p>Since the 1990s, Nozomu has been collecting samples and measurements from glaciers all over the world. When we reach our goal near the snowline, he opens his rucksack to reveal a bento box full of sampling kit – stainless steel scoops, test tubes, sample bags, all arranged for efficiency. As he scurries around with practised efficiency, I think of offering help but fear I would only slow him down.</p>
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<a href="https://images.theconversation.com/files/532612/original/file-20230619-27-w8e0xr.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Scientist takes a reading in snowy Arctic landscape" src="https://images.theconversation.com/files/532612/original/file-20230619-27-w8e0xr.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/532612/original/file-20230619-27-w8e0xr.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=424&fit=crop&dpr=1 600w, https://images.theconversation.com/files/532612/original/file-20230619-27-w8e0xr.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=424&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/532612/original/file-20230619-27-w8e0xr.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=424&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/532612/original/file-20230619-27-w8e0xr.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=533&fit=crop&dpr=1 754w, https://images.theconversation.com/files/532612/original/file-20230619-27-w8e0xr.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=533&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/532612/original/file-20230619-27-w8e0xr.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=533&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">Nozomu Takeuchi measuring the biological darkening of a Svalbard glacier in 2011.</span>
<span class="attribution"><span class="source">Arwyn Edwards</span>, <span class="license">Author provided</span></span>
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<p>In truth, Nozomu is decades ahead of us all. Years ago, he made the link between the future of life and the death of ice, and these melting Svalbard glaciers are adding yet more points to his graphs.</p>
<p>Just as we apply oodles of factor 50 to protect ourselves from the Sun, so the billions of microbes sandwiched between the sky and surface of the glacier protect themselves by accumulating sunscreen-like pigments. And if enough of these pigments rest in one place under the Sun, this area of “biological darkening” absorbs the heat of the Sun much more effectively than reflective white snow and ice – so it melts faster.</p>
<p>Nozomu scoops up some of the so-called blood snow, heavily laden with algae. Under the microscope, their cells are indeed reminiscent of red blood cells. But rather than haemoglobin, these cells are laden with carotenoids – pigments also found in vegetables that <a href="https://academic.oup.com/femsec/article/94/3/fiy007/4810544?login=false">protect the algae from overheating</a>. Other patches of the glacier are verdant green, rich in algae that are busy photosynthesising light into chemical energy in this 24-hour daylight world.</p>
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<a href="https://images.theconversation.com/files/532611/original/file-20230619-29-l44kho.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Man in icy landscape holding scientific sample" src="https://images.theconversation.com/files/532611/original/file-20230619-29-l44kho.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/532611/original/file-20230619-29-l44kho.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/532611/original/file-20230619-29-l44kho.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/532611/original/file-20230619-29-l44kho.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/532611/original/file-20230619-29-l44kho.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=565&fit=crop&dpr=1 754w, https://images.theconversation.com/files/532611/original/file-20230619-29-l44kho.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=565&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/532611/original/file-20230619-29-l44kho.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=565&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">The author with a sample of ‘blood snow’, collected from a glacier surface.</span>
<span class="attribution"><span class="source">Arwyn Edwards</span>, <span class="license">Author provided</span></span>
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<p>Further down the glacier, the professor crushes some “dirty” ice into a bag. A different kind of algae lives here that, depending on your point-of-view, is either black, brown or purple (perhaps it depends on the tint of your sunglasses). The <a href="https://www.researchgate.net/figure/Chemical-structure-of-compound-3-purpurogallin-carboxylic-acid-6-O-b-d-glucopyranoside_fig2_51806131#:%7E:text=A%20gallotannin%20derivative%20(galloylglucopyranose%2C%20i.e.,et%20al.%2C%202012b)%20.">pigment</a> created is like the compounds that colour tea, and the algae keep it in layers like parasols above the photosynthetic factories within their cells – ensuring they have just enough sunlight to photosynthesise, but not enough to burn.</p>
<p>Open Google Earth and as you zoom in on the Arctic, you may spot the large dark stripe that scars the western margin of the <a href="https://en.wikipedia.org/wiki/Greenland_ice_sheet">Greenland ice sheet</a>. This is the “dark zone”, but it’s not caused by dark <a href="https://www.nature.com/articles/s41467-020-20627-w">dust</a> or soot. It’s alive, <a href="https://www.nature.com/articles/ismej2012107">laden with algae</a> – and it has been darkening, and growing, as Greenland warms.</p>
<p>Between 2000 and 2014, the <a href="https://www.frontiersin.org/articles/10.3389/feart.2016.00043/full">dark zone’s area grew by 14%</a>. At 279,075 km² in 2012, it was already more than twice the <a href="https://www.britannica.com/summary/England#:%7E:text=Area%3A%2050%2C301%20sq%20mi%20(130%2C278,even%20with%20the%20entire%20kingdom.).%20This%20had%20a%20powerful%20impact%20on%20the%20rate%20of%20ice%20melt%20--%20areas%20blooming%20with%20algae%20%5Bmelt%20nearly%202cm%20more%20each%20day%5D(https://www.pnas.org/doi/abs/10.1073/pnas.1918412117">size of England</a> than bare ice.</p>
<p>Next morning, I am woken by the smell of chemicals, having slept beneath a coffee table. Nozomu is busy processing his samples: bags of melting ice pinned to a clothesline by bulldog clips. They resemble bunting around the crowded room, but this is no time for celebration. The tint of each bag adds a measurement which quantifies the link between these algae, their pigments, and the death of their icy home.</p>
<h2>The case becomes urgent</h2>
<p>By the summer of 2014, glaciologists all over the world have started to listen to the warnings of pioneering ecologists such as Nozomu. The glaciers are dying even as life blossoms on their darkening surfaces. The case has become urgent.</p>
<p>I am in a helicopter, flying with colleagues to a camp in the dark zone on the Greenland ice sheet – the largest mass of glacial ice in the northern hemisphere. Covering 1.7 million km², its ice holds the equivalent of the water required to raise global sea levels by 7.7 metres.</p>
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<span class="caption">A highly darkened surface of the Greenland ice sheet, rich in algae and incised with rivers of meltwater.</span>
<span class="attribution"><span class="source">Arwyn Edwards</span>, <span class="license">Author provided</span></span>
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<p>As we warm our climate, the rate of water flowing from this reservoir increases, with each degree Celsius added to global temperatures opening the drainage valve even wider. Feedback processes such as biological darkening have the potential to multiply the number of drainage valves that are open, hastening dramatically the rate at which sea levels rise.</p>
<p>To monitor this effect, every day <a href="https://www.gla.ac.uk/schools/ges/staff/karencameron/">Karen Cameron</a>, the leader of our camp this summer, walks to undisturbed patches of ice carrying a £100,000 backpack which contains a spectrometer to measure the darkness of the ice, capturing how it absorbs the solar energy that causes melting. The glaciologists are desperate for ground truth, and their models need data.</p>
<p>Up to this point, none of their predictions of how the Greenland ice sheet would respond to our warming climate have included biological darkening. Even if the effect were modest, it could still topple the ice sheet from a predictable, straightline response to climate warming.</p>
<p>All the time we are in Greenland, the only lifeforms we encounter are the flies that hatch from the fresh fruit and peppers in our food rations. These and the few types of glacier algae and several hundred kinds of bacteria that are biologically darkening the ice: a living scum scarring the surface of the ice sheet.</p>
<p>My work focuses on how these tiny organisms adapt to their icy habitat, but the implications of their behaviour are now of global concern. A <a href="https://screenworks.org.uk/archive/baftss-practice-research-award-2017/timeline">filmmaker</a> at the camp is weaving a thread between the ice melt in Greenland and its consequences for people living in coastal communities all over the world – from villages near my home on the <a href="https://www.theguardian.com/environment/2019/may/18/this-is-a-wake-up-call-the-villagers-who-could-be-britains-first-climate-refugees">west coast of Wales</a>, to huge metropolises like Manhattan, Amsterdam and Mumbai, and even entire low-lying island nations in the Pacific.</p>
<p>As smaller glaciers fade, and the larger ice sheets of Greenland and Antarctica start to respond with full force to our warming climate, it is these communities, capitals and countries that will bear the brunt of the flooding, inundation and erosion that comes with rising sea levels.</p>
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<a href="https://images.theconversation.com/files/532622/original/file-20230619-28-oh4l8z.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Two scientists inspecting an ice corer device dripping with meltwater." src="https://images.theconversation.com/files/532622/original/file-20230619-28-oh4l8z.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/532622/original/file-20230619-28-oh4l8z.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/532622/original/file-20230619-28-oh4l8z.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/532622/original/file-20230619-28-oh4l8z.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/532622/original/file-20230619-28-oh4l8z.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/532622/original/file-20230619-28-oh4l8z.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/532622/original/file-20230619-28-oh4l8z.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"></a>
<figcaption>
<span class="caption">The author (left) and Joseph Cook high on the Greenland ice sheet, meltwater dripping from their ice corer.</span>
<span class="attribution"><span class="source">Sara Penrhyn Jones</span>, <span class="license">Author provided</span></span>
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<p>Before heading home, our helicopter takes us on a detour, high over the ice sheet. We fly over the brown-black-purple algae to brighter, higher elevations where the palette shrinks to the blue and white of water and ice, then snow and sky. Greenland makes its own weather and, in these higher elevations, we expect the ice to be frozen all year round. When we land and begin to collect snow samples and a small ice core, however, we find we are digging into slush. The ice has started to melt up here, too. </p>
<p>We heave up our ice corer, and meltwater dribbles out from its bottom. In periods of extreme warming, much of the surface of the ice sheet can experience melting episodes, <a href="https://www.frontiersin.org/articles/10.3389/fmicb.2015.00225/full">disturbing the slumbering microbes</a> stored within the otherwise permanently frozen surface. It’s a sobering moment for us all.</p>
<p>Flying back to camp, I watch the streams become rivers and lakes as we head back over the dark zone, where melt and microbes dominate the icescape. I contemplate how much water, once locked in the ice, will become free to flow into the sea and into millions of homes by the end of the century.</p>
<h2>Popping a pingo</h2>
<p>The frozen lands of eight nations encircle the Arctic. Their soils store vast quantities of carbon: a third of the planet’s entire quantity of soil carbon resides in this frozen ground.</p>
<p>The carbon is a legacy of soils formed in past climates and preserved for millennia. However, human-induced climate change is reheating this leftover carbon, providing a luxuriant food source for microbes resident within the <a href="https://earthobservatory.nasa.gov/biome/biotundra.php">tundra</a>, which then emit it as greenhouse gases.</p>
<p>This is known as the <a href="https://en.wikipedia.org/wiki/Permafrost_carbon_cycle#:%7E:text=Carbon%20emissions%20from%20permafrost%20thaw,which%20increases%20permafrost%20thaw%20depths.">permafrost carbon</a> feedback loop. When even modest quantities of this vast carbon store reach the atmosphere, warming accelerates – resulting in faster thawing of the tundra and the release of yet more greenhouse gases.</p>
<p>Furthermore, not all greenhouse gases are equal in their impact. While carbon dioxide is relatively abundant and stable for centuries in the atmosphere, methane is less abundant and shorter-lived, but remarkably powerful as a greenhouse gas – nearly 30 times more damaging to the climate than carbon dioxide, for the same volume.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/532615/original/file-20230619-1823-ekek0j.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Scientist crouched on ice taking water samples." src="https://images.theconversation.com/files/532615/original/file-20230619-1823-ekek0j.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/532615/original/file-20230619-1823-ekek0j.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=307&fit=crop&dpr=1 600w, https://images.theconversation.com/files/532615/original/file-20230619-1823-ekek0j.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=307&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/532615/original/file-20230619-1823-ekek0j.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=307&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/532615/original/file-20230619-1823-ekek0j.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=386&fit=crop&dpr=1 754w, https://images.theconversation.com/files/532615/original/file-20230619-1823-ekek0j.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=386&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/532615/original/file-20230619-1823-ekek0j.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=386&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Andy Hodson sampling methane from a freshly ‘popped’ pingo.</span>
<span class="attribution"><span class="source">Arwyn Edwards</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>For more than three decades, <a href="https://www.unis.no/staff/andy-hodson/">Andy Hodson</a> has worked at the frontier where microbes, carbon and the Arctic landscape meet. In 2018, we join him on a brisk spring day in Svalbard. It’s -26°C but the snowmobile commute is thankfully brief – then we work quickly against the cold.</p>
<p>Hodson’s plan is to “pop” one of the many <a href="https://en.wikipedia.org/wiki/Pingo">pingos</a> that populate the floor of this wide open valley. Think of pingos as the acne of the Arctic: they form as permafrost compresses unfrozen wet sediments, erupting as small hills blistering the skin of the tundra.</p>
<p>The story of these microbes’ lives is complicated. They only live beyond the reach of oxygen – where oxygen is more prevalent, methane-consuming microbes thrive instead, quenching the belches of methane from below. Similarly, should mineral sources of iron or sulphide be nearby, then microbes that use them outcompete the methanogens.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/532614/original/file-20230619-15-6i78fv.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A small fountain of water in an opening in the ice, amid a snowy landscape." src="https://images.theconversation.com/files/532614/original/file-20230619-15-6i78fv.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/532614/original/file-20230619-15-6i78fv.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/532614/original/file-20230619-15-6i78fv.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/532614/original/file-20230619-15-6i78fv.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/532614/original/file-20230619-15-6i78fv.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/532614/original/file-20230619-15-6i78fv.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/532614/original/file-20230619-15-6i78fv.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"></a>
<figcaption>
<span class="caption">A popped pingo discharging supercooled water rich in methane.</span>
<span class="attribution"><span class="source">Arwyn Edwards</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>It all adds up to one of the greatest uncertainties for our civilisation: the extent and composition of greenhouse gases escaping from Arctic lands. <a href="https://www.cam.ac.uk/research/news/emissions-from-melting-permafrost-could-cost-43-trillion#:%7E:text=Increased%20greenhouse%20gas%20emissions%20from,and%20the%20University%20of%20Colorado.">Estimates of the economic impacts</a> from this permafrost carbon feedback tally in the tens of trillions of dollars to the global economy. We know it is bad news, but exactly how bad depends on the microbes in their microscopic mosaic.</p>
<p>Hodson’s field work shows that, during the Arctic winter, this pingo is probably the only source of methane in the immediate area, its chimney enabling the gas to escape from the depths of the ice before methane-consuming microbes can catch it. Annually, tens of kilograms of methane and more than a ton of carbon dioxide will escape from this pingo alone - one of <a href="https://doi.org/10.1016/j.geomorph.2023.108694">more than 10,000</a> scattered across the Arctic, in addition to its other methane-producing hotspots.</p>
<h2>A near-perfect ecosystem</h2>
<p>Arctic lands are a patchwork of permafrost carbon feedbacks, and our future depends on the uncertain fate of the microbes within. </p>
<p>While the ice melt enhances the growth of microbes in the short term, if it continues to the point of erasing habitats then the microbes will be lost with them. We recognise this danger for polar bears and walruses, but not the invisible biodiversity of the Arctic. Small does not mean insignificant though.</p>
<p>To appreciate this, we can head back to the dark zone on Greenland’s ice sheet and join <a href="https://www.rolex.org/rolex-awards/exploration/joseph-cook">Joseph Cook</a> during our summer 2014 field season. He’s lying on a mat improvised from a bath towel and a binbag wrapped in duct tape, peering into a dark, pothole-like depression in the ice. It’s a cryoconite hole, and millions of them are dotted over the edges of the ice sheet. Where pingos contribute to climate warming by emitting methane, cryoconite is a good sink of greenhouse gases, but this creates its own problems. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/532618/original/file-20230619-27-4a5amn.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Crouching scientist takes samples in the Arctic snow." src="https://images.theconversation.com/files/532618/original/file-20230619-27-4a5amn.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/532618/original/file-20230619-27-4a5amn.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/532618/original/file-20230619-27-4a5amn.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/532618/original/file-20230619-27-4a5amn.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/532618/original/file-20230619-27-4a5amn.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/532618/original/file-20230619-27-4a5amn.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/532618/original/file-20230619-27-4a5amn.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"></a>
<figcaption>
<span class="caption">Joseph Cook measuring the carbon cycling activities of Greenland’s cryoconite holes.</span>
<span class="attribution"><span class="source">Arwyn Edwards</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1365-2486.2008.01758.x">earliest estimate</a> of its ability to store carbon dioxide from the air on the ice surface of the world’s glaciers exceeded Finland’s total carbon emissions in the same year. Every cryoconite hole is a near-perfect ecosystem – with a singular flaw. Its inhabitants must melt ice to live. But the very act of melting the ice hastens the demise of their glacier habitat. </p>
<p>Despite being found in some of the harshest locations on Earth, cryoconite is home for thousands of different types of bacteria (including the all-important photosynthetic cyanobacteria), fungi, and <a href="https://microbiologysociety.org/why-microbiology-matters/what-is-microbiology/protozoa.html">protozoa</a>. Even <a href="https://www.theguardian.com/environment/2020/oct/17/tardigrade-ice-hole-arctic-greenland">tardigrades</a> thrive in cryoconite.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/532623/original/file-20230619-21-7v4otj.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Microscope image of a single cryoconite granule." src="https://images.theconversation.com/files/532623/original/file-20230619-21-7v4otj.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/532623/original/file-20230619-21-7v4otj.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/532623/original/file-20230619-21-7v4otj.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/532623/original/file-20230619-21-7v4otj.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/532623/original/file-20230619-21-7v4otj.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/532623/original/file-20230619-21-7v4otj.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/532623/original/file-20230619-21-7v4otj.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"></a>
<figcaption>
<span class="caption">Microscope image of a cryoconite granule, showing biological darkening and cyanobacteria growing through it.</span>
<span class="attribution"><span class="source">Arwyn Edwards</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Cook is professionally besotted with the perfection of this near-frozen “microscopic rainforest”. Its inhabitants are shielded and nourished at just the right depth and in the right shape for a busy ecosystem to be engineered by the interaction of sunlight with cyanobacteria, dust and ice to the benefit of all its inhabitants. The cyanobacteria use sunshine to capture carbon dioxide from the air and convert it into the slimy cement that builds each granule of cryoconite</p>
<p>However, with vast numbers of cryoconite holes dotted across the ice surface, “swarms” of these holes help <a href="https://www.frontiersin.org/articles/10.3389/feart.2015.00078/full">shape and darken the ice surface</a>. This in turn influences the melting rate, as the surface is sculpted under the sun of 24-hour daylight.</p>
<p>Writing in the scientific journal <a href="https://www.nature.com/articles/029039a0">Nature in 1883</a>, Swedish polar explorer Adolf Erik Nordenskjöld, who discovered cryoconite, thanked the organisms within cryoconite for melting away the ancient ice that once covered Norway and Sweden:</p>
<blockquote>
<p>In spite of their insignificance, [they] play a very important part in nature’s economy, from the fact that their dark colour far more readily absorbs the Sun’s heat than the bluish-white ice, and thereby they contribute to the destruction of the ice sheet, and prevent its extension. Undoubtedly we have, in no small degree, to thank these organisms for the melting away of the layer of ice which once covered the Scandinavian peninsula.</p>
</blockquote>
<h2>Taking DNA analysis to strange new places</h2>
<p>We return to Greenland in winter 2018 to explore cryoconite’s singular flaw. Cook and I are joined by Melanie Hay, then a PhD student in Arctic bioinformatics.</p>
<p>Hay and I are taking DNA analysis to strange new places to learn more about the evolution and biology of cryoconite. Powerful advances in genomics are changing our view of the microbial world, but large DNA-sequencing instruments fare best in sophisticated labs.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/532619/original/file-20230619-17-uv14gu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Scientist sitting outside her tent with backpack, looking out at icy landscape." src="https://images.theconversation.com/files/532619/original/file-20230619-17-uv14gu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/532619/original/file-20230619-17-uv14gu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=442&fit=crop&dpr=1 600w, https://images.theconversation.com/files/532619/original/file-20230619-17-uv14gu.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=442&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/532619/original/file-20230619-17-uv14gu.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=442&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/532619/original/file-20230619-17-uv14gu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=555&fit=crop&dpr=1 754w, https://images.theconversation.com/files/532619/original/file-20230619-17-uv14gu.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=555&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/532619/original/file-20230619-17-uv14gu.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=555&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Melanie Hay camping and sampling on the Greenland ice sheet.</span>
<span class="attribution"><span class="source">Arwyn Edwards</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Instead, we are using a stapler-sized nanopore sequencer hooked up to the USB port of a winterised laptop. Outside the tent, it is –20°C – but the DNA sequencer must run at body temperature. The only sustainable source of warmth is body heat, so I have snuggled up with the sequencer in my sleeping bag every night and in my clothes all day.</p>
<p>That evening, we are caught in a storm of hurricane force. Becoming disorientated while moving between tents would be lethal, so we crawl in a human chain through the whiteout to our sleeping tents. Hay reaches her tent but Cook’s is lost, so we squeeze into my one-person tent. Somehow I sleep soundly, while Cook is exposed to the full force of the night’s terror.</p>
<p>In the morning, we excavate Hay, whose snow-laden tent had collapsed in the night. The sequencing is complete, but storm damage to our generator means the camp is losing power, so she must work quickly. She identifies the cyanobacteria building the cryoconite – it’s a short list dominated by one species: <em>Phormidesmis priestleyi</em>.</p>
<p>This species, found in cryoconite throughout the Arctic, seems to be the ecosystem engineer of cryoconite – a microscopic beaver building a dam of dust. But the flaw is the darkness of the near-perfect cryoconite ecosystems it creates. Like the neighbouring glacier algae we met earlier, <em>Phormidesmis priestleyi</em> is biologically darkening Arctic ice, and eventually hastening the demise of the thousands of different types of organism contained in cryoconite holes.</p>
<p>And so, this work shows us ever more clearly that the <a href="https://www.nature.com/articles/s41559-020-1163-0">loss of the planet’s glaciers</a> is as much a component of the global biodiversity crisis as it is a headline impact of climate change.</p>
<h2>Last line of defence against antibiotic resistance</h2>
<p>The loss of the Arctic’s microbial biodiversity matters in other ways too. Hay and Aliyah Debbonaire are both reformed biomedical scientists seeking cures from the Arctic in the form of new antibiotics. In the summer of 2018, we are in Svalbard looking for clues.</p>
<p>The world is running out of effective antibiotics, and the Arctic’s frontiers may be our last line of defence in this antibiotic resistance crisis. Countless species of microbes have evolved to live within its harsh habitats using all the tricks in the book, including making antibiotics as chemical weapons to kill off competitors. This means they may be sources of new antibiotics.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/532631/original/file-20230619-1900-kr9gwx.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Scientists (one kneeling) taking samples in the snowy Arctic landscape." src="https://images.theconversation.com/files/532631/original/file-20230619-1900-kr9gwx.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/532631/original/file-20230619-1900-kr9gwx.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=413&fit=crop&dpr=1 600w, https://images.theconversation.com/files/532631/original/file-20230619-1900-kr9gwx.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=413&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/532631/original/file-20230619-1900-kr9gwx.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=413&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/532631/original/file-20230619-1900-kr9gwx.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=519&fit=crop&dpr=1 754w, https://images.theconversation.com/files/532631/original/file-20230619-1900-kr9gwx.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=519&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/532631/original/file-20230619-1900-kr9gwx.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=519&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Aliyah Debbonaire (left) and Melanie Hay sampling a cryoconite hole.</span>
<span class="attribution"><span class="source">Arwyn Edwards</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>And this is not their only application. From cheeses to eco-friendly biological washing powders, entire shopping aisles of products have been derived from cold-adapted microbes. As climate warming threatens to disrupt entire Arctic habitats, our opportunity to use, learn from, and protect this biodiversity may be lost forever.</p>
<p>As our tiny plane returns to the nearest town, Longyearbyen, we fly low over the <a href="https://theconversation.com/after-svalbard-why-safety-of-world-seed-vaults-is-crucial-to-future-food-security-79586">Svalbard Global Seed Vault</a>, which contains the fruits of more than 12,000 years of agriculture in the form of seeds from a million different varieties of crop. Nearby, a similar facility inside a disused coal mine stores essential computer programmes on microfilm – the ultimate backup for our data-addicted world.</p>
<p>Within a snowy kilometre, you can walk between the the alpha and omega of human innovation in civilisation. Both facilities have chosen the fastest-warming town on the planet as the safest place to store these treasures of humanity. Yet no such facility is dedicated to the microbial biodiversity of the Arctic, despite its critical importance to the future of the world’s biotech and medical sectors.</p>
<p>Instead, it falls to microbiologists such as Debbonaire, racing against time to identify, nurture and screen the microbes of the melting Arctic. Her painstaking work accumulates towers of Petri dishes, each a temporary refuge for a different Arctic microbe.</p>
<p>Eventually, they will be stored in <a href="https://www.dellamarca.it/en/how-does-an-ultra-low-freezer-work/">ultra-freezers</a> in laboratories scattered across the world. Such work is unglamorous to funders, so it is done piecemeal on the edges of other projects. Yet it represents our only attempt to save the microbes of the Arctic.</p>
<h2>The battle is lost</h2>
<p>Most of all, the Arctic matters because it is the fastest-warming part of the planet, and its microbes are responding first. What happens there carries implications for everyone. It is the harbinger of change for everywhere.</p>
<p>Another Arctic microbiologist could strike plangent notes regarding permafrost or sea ice, but as an ecologist of glaciers I am drawn to glacial ice.</p>
<p>Over the first fifth of this century, Earth’s glaciers have discharged some ten quadrillion (ten to the power 25) tablespoons of melt a year – and within each tablespoon, the <a href="https://www.nature.com/articles/s43247-022-00609-0">tens of thousands of bacteria and viruses</a> that were once stored within that ice.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/meltwater-is-infiltrating-greenlands-ice-sheet-through-millions-of-hairline-cracks-destabilizing-its-structure-207468">Meltwater is infiltrating Greenland’s ice sheet through millions of hairline cracks – destabilizing its structure</a>
</strong>
</em>
</p>
<hr>
<p>What’s to come is sadly predictable. Even the most modest warming scenario of 1.5°C above the pre-industrial era will lead to the extinction of at least <a href="https://www.science.org/doi/10.1126/science.abo1324">half the Earth’s 200,000 glaciers</a> by the end of the century.</p>
<p>Depending on the urgency and effectiveness of our actions as a civilisation, this century could also represent the “peak melt” in our history. Yet the battle to save many of these precious icy habitats is already lost. Instead, for scientists like me, our field work is now largely a question of documenting these “crime scenes” – so at least the knowledge of life within ice can be preserved, before it melts away forever.</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>
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<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/207785/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Arwyn Edwards receives funding from UK Research & Innovation - Natural Environment Research Council, as well as the Research Council of Norway, the Leverhulme Trust, and the Royal Geographical Society. </span></em></p>To fully understand the extent of climate-related dangers the Arctic – and our planet – is facing, we must focus on organisms too small to be seen with the naked eye.Arwyn Edwards, Reader in Biology, Department of Life Sciences, Aberystwyth UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2049832023-05-11T12:59:30Z2023-05-11T12:59:30ZMicroplastics: we’ve found startling quantities in the ice algae that are essential for all Arctic marine life<p>Last summer, we travelled to the remote Arctic Hausgarten observatory area in the eastern Fram Strait (west of Svalbard, Norway) on a <a href="https://www.awi.de/en/expedition/research-vessel-and-cutter/polarstern.html">research ship</a>. The samples we collected there included ice cores, sea water and ice algae from large packs of floating ice called ice floes. These form 1–2 metre thick “plates” of sea ice across the Arctic Ocean, some of which melt over the summer period. </p>
<p>Algae grow on the underside of these ice floes. <em>Melosira arctica</em> – nicknamed “snot” due to its sticky, slimy and green nature – is one of the major algae species in the Arctic Ocean. It is an essential organism both in the Arctic food web and for marine life overall.</p>
<p>These ice algae provide nutrition for plankton and various other marine organisms in the Arctic. The algae also act as a <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0076599">conveyor belt of food</a> for the organisms that live on the sea floor. As the ice melts, the algae detach and sink to the bottom where they are eaten by animals such as <a href="https://www.britannica.com/animal/sea-cucumber">sea cucumbers</a> and <a href="https://www.britannica.com/animal/brittle-star">brittlestars</a>. </p>
<p>Ice algae are also a carbon sink, using CO₂ from the atmosphere and light energy from the sun to produce organic matter through photosynthesis – a process known in ecology as “<a href="https://www.nature.com/articles/s41467-023-37612-8">primary production</a>”. In 2012, these algae <a href="https://www.science.org/doi/10.1126/science.1231346">accounted for 45%</a> of the Arctic’s primary production.</p>
<p>But now <a href="https://pubs.acs.org/doi/10.1021/acs.est.2c08010">we’ve found</a> that Arctic ice algae contain microplastics. This in itself may not be surprising: plastic has been found in <a href="https://doi.org/10.1016/j.hazadv.2022.100057">every environment</a> so far investigated on Earth. But the quantities we found were startling. </p>
<p>We discovered an average of 31,000 microplastic particles per cubic metre of <em>Melosira arctica</em> – a magnitude ten times higher than recorded in the surrounding water. Most of these particles were very small (less than 10 micrometres) and included many different types of plastic. The contamination of the ice algae could have major consequences for ecosystems and the climate.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/524606/original/file-20230505-15-3dxxqs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Four images of Melosira arctica algae." src="https://images.theconversation.com/files/524606/original/file-20230505-15-3dxxqs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/524606/original/file-20230505-15-3dxxqs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=365&fit=crop&dpr=1 600w, https://images.theconversation.com/files/524606/original/file-20230505-15-3dxxqs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=365&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/524606/original/file-20230505-15-3dxxqs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=365&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/524606/original/file-20230505-15-3dxxqs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=459&fit=crop&dpr=1 754w, https://images.theconversation.com/files/524606/original/file-20230505-15-3dxxqs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=459&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/524606/original/file-20230505-15-3dxxqs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=459&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption"><em>Melosira arctica</em>, one of the major algae species in the Arctic Ocean.</span>
<span class="attribution"><span class="source">Melanie Bergmann</span>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<h2>An elevator to the seabed</h2>
<p>These particles may come from the surrounding sea water, the <a href="https://www.nature.com/articles/s41467-018-03825-5">supporting sea ice</a> (either trapped when the sea ice forms, or from the movement of liquid and particles through the ice as it melts), or from <a href="https://www.nature.com/articles/s43017-022-00292-x">atmospheric microplastics</a> that have been deposited on the ice and sea surface. While the process by which sea ice algae take in these microplastics is not yet well understood, it is clear they are highly effective at “collecting” these small plastic particles.</p>
<p>In <a href="https://pubs.acs.org/doi/10.1021/acs.est.9b06981">our earlier research</a>, we were puzzled that the largest amount of microplastic on the Arctic seabed was always found underneath the sea ice melting zone along the ice edge, even in deep-sea sediment. The movement of <em>Melosira</em> clumps from the sea and ice surface to the seabed helps to explain why. </p>
<p>The speed at which the algal clumps descend means they fall rapidly almost in a straight line below the edge of the ice. Other algae, which become “marine snow” (a term used for organic material that slowly drifts to the seafloor), fall much slower. These are often eaten as they descend and are also pushed sideways by currents, so sink to the seabed much further away from the ice edge.</p>
<figure class="align-center ">
<img alt="A graph showing how microplastics could become trapped in Arctic sea ice algae and sink to the seabed." src="https://images.theconversation.com/files/524607/original/file-20230505-25-au50ge.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/524607/original/file-20230505-25-au50ge.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=426&fit=crop&dpr=1 600w, https://images.theconversation.com/files/524607/original/file-20230505-25-au50ge.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=426&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/524607/original/file-20230505-25-au50ge.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=426&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/524607/original/file-20230505-25-au50ge.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=535&fit=crop&dpr=1 754w, https://images.theconversation.com/files/524607/original/file-20230505-25-au50ge.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=535&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/524607/original/file-20230505-25-au50ge.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=535&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">How microplastics could become trapped in Arctic sea ice algae and sink to the seabed.</span>
<span class="attribution"><a class="source" href="https://creativecommons.org/licenses/by/4.0/">Bergmann et al. (2023)</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<h2>Why is it a problem?</h2>
<p><em>Melosira</em> feeds essential Arctic <a href="https://link.springer.com/article/10.1007/s00300-014-1634-3">seafloor</a> and marine ecosystems. Its position at the bottom of the food chain means there is a risk of microplastics being passed upwards through the marine food web.</p>
<p>This threat is particularly acute in the area we studied, as the <em>Melosira</em> sampled had collected even very small microplastics. Smaller microplastic particles are more likely to be transferred across cell membranes.</p>
<figure class="align-center ">
<img alt="Three researchers on an Arctic ice floe sampling for ice algae." src="https://images.theconversation.com/files/524603/original/file-20230505-23-3dxxqs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/524603/original/file-20230505-23-3dxxqs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/524603/original/file-20230505-23-3dxxqs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/524603/original/file-20230505-23-3dxxqs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/524603/original/file-20230505-23-3dxxqs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/524603/original/file-20230505-23-3dxxqs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/524603/original/file-20230505-23-3dxxqs.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">Ice algae sampling on an Arctic ice floe.</span>
<span class="attribution"><span class="source">Mario Hoppmann/Alfred Wegener Institute</span>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<p>Research finds that microplastics and their associated chemicals can alter the <a href="https://zenodo.org/record/5898684#.YjRGUzUxl6X">growth, function and breeding</a> of marine species such as plankton and fish. It is extremely difficult to perform experiments on Arctic or deep-sea species because of the challenges associated with replicating their environmental conditions. However, <a href="https://www.sciencedirect.com/science/article/pii/S0166445X20303817">one laboratory study</a> found that microplastic exposure caused egg production rates to increase by up to eight times in Arctic zooplankton – a response that is probably the result of stress. </p>
<p>The impact of microplastic contamination on <em>Melosira</em> itself is not yet known. But it’s possible that microplastics change <em>Melosira’s</em> abundance, lifespan and health. </p>
<p>Microplastics that are stuck to the outside of algae could lower photosynthetic rates by blocking out sunlight. And if particles enter the algal cells, then they could damage the parts of the cell where photosynthesis takes place (called chloroplasts) and therefore also impede this process. This could affect the export of carbon by <em>Melosira</em> from the air or sea to the seabed, and thus alter the processes underlying this important Arctic carbon sink.</p>
<p>Arctic ice algae are collecting high quantities of microplastics – a previously unknown hotspot. But our findings are likely just the “tip of the iceberg”. They should accelerate conversations about the importance, and potential impact, of microplastics in Arctic sea ice algae on the ecosystems that these vital algae support.</p><img src="https://counter.theconversation.com/content/204983/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Deonie Allen received funding from Leverhulme Trust through grant ECF-2019-306 and the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement no. 101023635.</span></em></p><p class="fine-print"><em><span>Melanie Bergmann receives funding from German Government via the Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research. </span></em></p><p class="fine-print"><em><span>steve allen receives funding from the Canadian government through Ocean frontiers Institute.</span></em></p>Arctic sea ice algae contaminated with microplastics have serious consequences for ecosystems and the climate.Deonie Allen, Research Fellow in Geography, Earth and Environmental Sciences, University of BirminghamMelanie Bergmann, Senior Scientist, Alfred Wegener Institute Helmholtz Centre for Polar and Marine ResearchSteve Allen, Ocean Frontier Institute researcher, Dalhousie UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1913152023-04-26T12:29:17Z2023-04-26T12:29:17ZArctic sea ice loss and fierce storms leave Kivalina’s volunteer Search and Rescue fighting to protect their island from climate disasters<figure><img src="https://images.theconversation.com/files/520352/original/file-20230411-24-kd0zun.jpg?ixlib=rb-1.1.0&rect=0%2C17%2C3000%2C1944&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Kivalina sits on a narrow barrier island on the Chukchi Sea.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/an-aerial-view-from-a-drone-shows-the-village-of-kivalina-news-photo/1175058955?adppopup=true">Joe Raedle/Getty Images</a></span></figcaption></figure><p>As winds and waves from Typhoon Merbok <a href="https://www.ktoo.org/2022/09/17/powerful-storm-slams-western-alaska/">devastated communities</a> along the coast of Western Alaska in 2022, Reppi Swan Sr.’s phone began to ring at Kivalina, a barrier island 80 miles above the Arctic Circle.</p>
<p>A neighboring family had lost 3 feet of land to the rumbling lagoon, and their home was now sitting just 6 feet from the angry water’s edge. Reppi called his brother Joe Swan Jr. and quickly slid into his insulated rain gear.</p>
<p>As a volunteer first responder, Reppi plans for emergencies like this. He and his wife, Dolly, had been patrolling the island for dangerous erosion every few hours during the storm. To prepare, he had already inspected the city’s heavy equipment and located a pile of boulders left over from a recent construction project.</p>
<p>Working through the rain, Reppi delivered boulders to the threatened home. With their cousin Carl Swan serving as a spotter, Joe carefully arranged the boulders with a backhoe to stabilize the bank. It would hold at least until the storm subsided.</p>
<p><img src="https://cdn.theconversation.com/static_files/files/2632/kiva3.gif?1681231737" width="100%" height="100%"> </p><figure><figcaption><span class="caption">Joe Swan Jr. and Carl Swan rush to arrange boulders to protect a home from erosion during Typhoon Merbok. The corner of the home is visible on the right. Video by Janet Mitchell</span></figcaption></figure> <p></p>
<p>With <a href="https://doi.org/10.1139/as-2017-0024">protective sea ice declining</a> and warming Pacific waters supercharging <a href="https://theconversation.com/typhoon-merbok-fueled-by-unusually-warm-pacific-ocean-pounded-alaskas-vulnerable-coastal-communities-at-a-critical-time-190898">fall storms</a> in the Bering and Chukchi seas, Alaska Native villages like Kivalina are experiencing growing risks to coastal livelihoods and critical infrastructure, including runways. Reppi’s efforts reflect the challenges many front-line communities face as they struggle with the effects of climate change.</p>
<h2>Dealing with disasters has become normal</h2>
<p>Indigenous governments, nonprofits, hunters and first responders from Iñupiaq, Yupik and Unangan communities across Alaska have long been preparing for today’s climate hazards. They have created initiatives from <a href="http://www.thearcticsounder.com/article/2234inupiaq_researcher_documents_how_climate">coastal monitoring</a> to relocation planning, yet <a href="https://www.gao.gov/assets/gao-09-551.pdf">state and federal support programs</a> are <a href="https://www.gao.gov/assets/gao-09-551.pdf">underfunded</a> and <a href="https://www.adn.com/alaska-news/rural-alaska/2022/05/30/rural-alaska-villages-hope-to-eliminate-barriers-to-federal-funding-for-addressing-climate-change-threats/">poorly structured</a> for the scale of today’s challenges.</p>
<p>Kivalina, an Iñupiaq community of 500 people, has been dealing with climate-fueled erosion and flooding for decades. Nearly 20 years ago, it was one of four villages the U.S. government determined to be facing “<a href="https://www.gao.gov/assets/gao-04-142.pdf">imminent danger</a>.” In 2009, <a href="https://www.gao.gov/products/gao-09-551">27 additional villages</a> were added to the list.</p>
<p>Over the years, Reppi, Joe and scores of other volunteers in Kivalina have improvised sea walls with everything from sandbags to sheets of metal cut from the chassis of an abandoned fuel plane. </p>
<figure class="align-center ">
<img alt="A profile image of Reppi swan, wearing a cap and camoflauge jacket" src="https://images.theconversation.com/files/519887/original/file-20230406-28-vzkh68.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/519887/original/file-20230406-28-vzkh68.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/519887/original/file-20230406-28-vzkh68.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/519887/original/file-20230406-28-vzkh68.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/519887/original/file-20230406-28-vzkh68.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/519887/original/file-20230406-28-vzkh68.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/519887/original/file-20230406-28-vzkh68.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">For Reppi Swan Sr., president of Kivalina’s Volunteer Search and Rescue, responding to disasters has become a normal part of everyday life.</span>
<span class="attribution"><span class="source">Kirk Koenig</span></span>
</figcaption>
</figure>
<p>As a field officer during such incidents, Reppi reflects on how difficult it is to send anyone into harm’s way, whether to search for a lost hunter or to save homes and infrastructure. He remembers one storm in which he put a lifeline on his volunteers as they tried to bolster the shoreline. “That was the hardest thing I had to do,” Reppi recalls, “because one of my guys had to stay down there and tie each super sack together. To top that off, the 8-foot to 10-foot waves would just engulf them completely.”</p>
<p>He talks about Typhoon Merbok with the calm of someone for whom storm readiness and response have become normal parts of everyday life. Because they have.</p>
<h2>‘We just can’t adapt this fast’</h2>
<p>For Indigenous nations around the world, the roots of climate risk today are often <a href="https://centerclimatejustice.universityofcalifornia.edu/posts/indigenous-peoples-and-climate-justice-by-kyle-powys-whyte/">colonial in origin</a>. Kivalina’s “<a href="http://www.alaskool.org/native_ed/historicdocs/kivalina/ki900012.htm">uneasiness</a>” with fall storms began shortly after 1905, when the U.S. Office of Education built a school on the island, and began a multidecade process to forcibly settle the autonomous and seminomadic <a href="https://upcolorado.com/university-of-alaska-press/item/5846-the-inupiaq-eskimo-nations-of-northwest-alaska">Kivalliñiġmiut nation</a>.</p>
<p>In 1981, after decades of deliberation, Kivalina’s municipal government initiated relocation planning as a means to gain running water and sewer services and to alleviate overcrowding. It was an attempt, as the elder Joe Swan Sr. puts it, to gain “breathing room” so that future generations might flourish. However, planning stalled in 2008 because of a disagreement between traditional knowledge holders in Kivalina and the <a href="https://www.poa.usace.army.mil/Portals/34/docs/civilworks/reports/KivalinaMasterPlanMainReportJune2006.pdf">U.S. Army Corps of Engineers</a> over the suitability of the community’s chosen site.</p>
<p>Kivalina’s relocation has now come to be framed as a response to climate change, but the initial needs that drove relocation planning still remain.</p>
<figure class="align-center ">
<img alt="A woman wearing a fleece jacket and sunglasses sits in a doorway with her arms crossed." src="https://images.theconversation.com/files/520351/original/file-20230411-16-phj7w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/520351/original/file-20230411-16-phj7w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=422&fit=crop&dpr=1 600w, https://images.theconversation.com/files/520351/original/file-20230411-16-phj7w.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=422&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/520351/original/file-20230411-16-phj7w.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=422&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/520351/original/file-20230411-16-phj7w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=530&fit=crop&dpr=1 754w, https://images.theconversation.com/files/520351/original/file-20230411-16-phj7w.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=530&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/520351/original/file-20230411-16-phj7w.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=530&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Colleen Swan has been involved in disaster response for decades and has seen an increase in the damage to her island home.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/city-administrator-colleen-swan-relaxes-at-the-end-of-a-day-news-photo/1175057581">Joe Raedle/Getty Images</a></span>
</figcaption>
</figure>
<p>“We’re an adaptable people,” Colleen Swan, Kivalina’s city administrator, told me when I started my doctoral studies 12 years ago, “but since 2004, we just can’t adapt this fast.” </p>
<p>That was the year pieces of the island began shearing off into the sea.</p>
<h2>The local value of the Arctic’s diminishing sea ice</h2>
<p>Historically, Kivalina’s sea ice would form early enough to protect the coast from fall storms. But with climate change, it forms much later, if at all, leaving the shoreline <a href="https://doi.org/10.1139/as-2017-0024">vulnerable to increased wave activity</a>. </p>
<p>On March 6, 2023, when Arctic sea ice hit its maximum extent for the year, it was the <a href="https://nsidc.org/arcticseaicenews/2023/03/arctic-sea-ice-maximum-at-fifth-lowest-on-satellite-record/">fifth-lowest maximum extent on the satellite record</a>. Kivalina had open water less then 2 miles (3.2 km) out from town, a fraction of what’s needed for a successful bowhead whale hunt.</p>
<figure class="align-center ">
<img alt="A snow and ice covered ocean with the edge of the island and its homes on one side. It looks cold out." src="https://images.theconversation.com/files/520329/original/file-20230411-16-5l672a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/520329/original/file-20230411-16-5l672a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/520329/original/file-20230411-16-5l672a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/520329/original/file-20230411-16-5l672a.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/520329/original/file-20230411-16-5l672a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=565&fit=crop&dpr=1 754w, https://images.theconversation.com/files/520329/original/file-20230411-16-5l672a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=565&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/520329/original/file-20230411-16-5l672a.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=565&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">During winter, sea ice protects the island from erosion, but Arctic ice is diminishing. This photo was taken in February 2021.</span>
<span class="attribution"><span class="source">Replogle Swan Sr.</span></span>
</figcaption>
</figure>
<p><iframe id="NuxVz" class="tc-infographic-datawrapper" src="https://datawrapper.dwcdn.net/NuxVz/9/" height="400px" width="100%" style="border: none" frameborder="0"></iframe></p>
<p>In 2008, Colleen was among local leaders who initiated the landmark climate justice lawsuit <a href="http://climatecasechart.com/case/native-village-of-kivalina-v-exxonmobil-corp/">Kivalina v. ExxonMobil</a>. The community sought up to US$400 million in restitution from the 24 largest greenhouse gas emitters in the U.S., companies whose profits are driving climate change. That would have been enough <a href="https://www.poa.usace.army.mil/Portals/34/docs/civilworks/reports/KivalinaMasterPlanMainReportJune2006.pdf">to cover the costs</a> of comprehensive village relocation. </p>
<p>The case was <a href="https://www.govinfo.gov/app/details/USCOURTS-ca9-09-17490/context">dismissed by a federal court</a>, a decision upheld by the 9th U.S. Circuit Court of Appeals in 2012. On May 20, 2013, the Supreme Court <a href="http://climatecasechart.com/case/native-village-of-kivalina-v-exxonmobil-corp/">refused to consider</a> any further appeal.</p>
<p>With the media attention generated by the lawsuit, Colleen has become globally recognized as a front-line leader for climate justice. She has <a href="https://www.sciencefriday.com/person/colleen-swan/">spoken across the U.S.</a> and was part of an <a href="https://www.ienearth.org/">Indigenous delegation</a> to the U.N. climate change conference in Copenhagen in 2009. Today, she’s busy addressing climate change on a different scale.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/520350/original/file-20230411-797-9exvac.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="An aerial view of Kivalina shows the boulders surrounding parts of the narrow island." src="https://images.theconversation.com/files/520350/original/file-20230411-797-9exvac.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/520350/original/file-20230411-797-9exvac.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/520350/original/file-20230411-797-9exvac.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/520350/original/file-20230411-797-9exvac.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/520350/original/file-20230411-797-9exvac.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/520350/original/file-20230411-797-9exvac.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/520350/original/file-20230411-797-9exvac.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"></a>
<figcaption>
<span class="caption">The Army Corps of Engineers built a rock revetment in 2008-2009 to help buffer Kivalina’s shore, but it does not surround the entire island.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/an-aerial-view-from-a-drone-shows-kivalina-which-is-at-the-news-photo/1175057966">Joe Raedle/Getty Images</a></span>
</figcaption>
</figure>
<p>Colleen now manages Kivalina’s Volunteer Search and Rescue, known as SAR, and her brother Reppi serves as its president. Kivalina SAR is an association of hunters and first responders that plays a crucial role in community safety, coastal resilience and hunter support. But climate change has changed the nature of the organization.</p>
<p>“In the past, search and rescue looked for people who were lost or late returning from a hunt.” But with late freeze-up, thin ice and melting permafrost, she explains, “We’re spending more time helping people because of changes to environmental conditions.” Through fundraising, capacity building, and <a href="https://www.kvlseaice.org/">strategic partnerships</a>, Colleen is building up SAR to respond to new hazards as it faces a rapidly changing environment.</p>
<h2>Infrastructure investments remain unfinished</h2>
<p>From 2008 to 2009, the Army Corps of Engineers constructed 1,600 feet of a planned 2,000-foot <a href="https://www.gao.gov/assets/gao-09-551.pdf">rock revetment wall</a> to help protect the island. These partial protections, built when funds were available, have been effective, but they leave critical infrastructure and lagoonside homes exposed – as Typhoon Merbok made clear. As Reppi tells me, “We’re always going to have erosion.”</p>
<p>When erosion from fall storms threatened the airport runway in 2019, city leaders made the difficult decision to redeploy boulders from the existing rock revetment.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/519888/original/file-20230406-26-39xzyh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="An aerial photo of the coast showing a rock border on the coast ending and erosion clearly evident beyond it." src="https://images.theconversation.com/files/519888/original/file-20230406-26-39xzyh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/519888/original/file-20230406-26-39xzyh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/519888/original/file-20230406-26-39xzyh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/519888/original/file-20230406-26-39xzyh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/519888/original/file-20230406-26-39xzyh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/519888/original/file-20230406-26-39xzyh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/519888/original/file-20230406-26-39xzyh.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">Where the rock revetment ends, homes and infrastructure face a high risk of erosion during storms. During Typhoon Merbok, volunteers gathered a new pile of boulders to try to protect homes.</span>
<span class="attribution"><span class="source">Janet Mitchell</span></span>
</figcaption>
</figure>
<p>Without comprehensive planning and funding, key segments of the community remain at risk. Kivalina’s first responders must remain vigilant.</p>
<p>After 10 years of lobbying state and federal agencies, Kivalina’s tribal and city councils secured an 8-mile evacuation road to Kisimiġiuqtuq Hill that opened in November 2020. With the state of Alaska <a href="https://www.adn.com/alaska-news/article/state-settles-historic-lawsuit-over-village-school-funding/2011/10/05/">compelled by a lawsuit</a> to remedy its systemic underfunding of Alaska Native schools, the Northwest Arctic Borough School District joined the project, opening a new school at Kisimiġiuqtuq Hill in <a href="http://www.thearcticsounder.com/article/2246the_new_kivalina_school_opened_its_doors_to">November 2022</a>.</p>
<p>Yet these achievements have also brought new concerns, and Reppi and Colleen are preparing their volunteers to respond to other types of problems, such as road accidents or stranded vehicles.</p>
<figure class="align-center ">
<img alt="Two men look at erosion that has exposed several feet of pipe. Rocks help protect part of the property." src="https://images.theconversation.com/files/519893/original/file-20230406-22-iuxkz7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/519893/original/file-20230406-22-iuxkz7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/519893/original/file-20230406-22-iuxkz7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/519893/original/file-20230406-22-iuxkz7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/519893/original/file-20230406-22-iuxkz7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/519893/original/file-20230406-22-iuxkz7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/519893/original/file-20230406-22-iuxkz7.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">Reppi Swan Sr. and Joe Swan Jr. inspect an eroded property they shored up during a storm.</span>
<span class="attribution"><span class="source">Janet Mitchell</span></span>
</figcaption>
</figure>
<p>Since Kivalina’s Search and Rescue purchased its first truck in the summer of 2021, Reppi has made regular patrols to study every bend of the poorly lit and steeply pitched road – often through blowing snow. When Kivalina’s children began riding a school bus for the first time, he followed close behind – up and back, three times a day – just in case.</p>
<p>At times this winter, Kivalina’s school bus has been without a certified driver, or sidelined with mechanical issues. When the transportation burden falls on individual families, those without a vehicle, or unable to afford the <a href="https://storymaps.arcgis.com/stories/429b4ff23f2648e0b46f38c8aeff09d2">high cost of fuel</a>, are missing school outright. Lacking adequate snow removal equipment, heavy snow and high winds kept Kivalina’s school closed the entire month of March. </p>
<h2>Community efforts fill critical adaptation gap</h2>
<p>While Kivalina, like many other Indigenous communities, has been clear about its climate adaptation priorities, support from federal and international institutions has been limited. </p>
<p>The Biden administration recently made <a href="https://www.doi.gov/pressreleases/biden-harris-administration-makes-135-million-commitment-support-relocation-tribal">$115 million available</a> to help 11 Indigenous communities with relocation, but the Army Corps estimated Kivalina alone would <a href="https://www.poa.usace.army.mil/Portals/34/docs/civilworks/reports/KivalinaMasterPlanMainReportJune2006.pdf">need $250 million to $400 million</a>. Kivalina wasn’t on the list.</p>
<p>Indigenous coastal communities bear a <a href="https://www.epa.gov/climateimpacts/climate-change-and-health-indigenous-populations">disproportionate amount of risk</a> from climate change, and the costs of adaptation often go uncompensated. Without comprehensive investment in local priorities – from planning and infrastructure to capacity-building – organizations like Kivalina’s Search and Rescue will continue to fill a critical gap, performing the invisible labor of climate adaptation.</p>
<p><em>This article, originally published April 26, 2023, has been updated with the date the Supreme Court declined Kivalina’s appeal, one decade ago.</em></p><img src="https://counter.theconversation.com/content/191315/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>P. Joshua Griffin co-directs "Polar Science at a Human Scale" with Reppi Swan Sr. and Colleen Swan. Since 2020, their work has received funding from the University of Washington EarthLab, the UW Center for American Indian and Indigenous Studies, and the UW Program on Climate Change.</span></em></p>In the years since the Supreme Court rejected Kivalina’s appeal on May 20, 2013, the community’s search and rescue team has faced increasing climate disasters: ‘We just can’t adapt this fast.’P. Joshua Griffin, Assistant Professor of Marine and Environmental Affairs and American Indian Studies, University of WashingtonLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1962542022-12-13T16:01:45Z2022-12-13T16:01:45ZArctic Report Card 2022: The Arctic is getting rainier and seasons are shifting, with broad disturbances for people, ecosystems and wildlife<figure><img src="https://images.theconversation.com/files/500768/original/file-20221213-10619-mim3qd.jpg?ixlib=rb-1.1.0&rect=24%2C8%2C5439%2C3628&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Rainier winters make life more difficult for Arctic wildlife and the humans who rely on them.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/reindeer-herd-in-mid-winter-norwegian-arctic-january-27th-news-photo/608180463">Scott Wallace/Getty Image</a></span></figcaption></figure><p>In the Arctic, the freedom to travel, hunt and make day-to-day decisions is profoundly tied to cold and frozen conditions for much of the year. These conditions are rapidly changing as the Arctic warms.</p>
<p>The Arctic is now seeing more rainfall when historically it would be snowing. Sea ice that once protected coastlines from erosion during fall storms is forming later. And thinner river and lake ice is making travel by snowmobile increasingly life-threatening. </p>
<p>Ship traffic in the Arctic is also increasing, bringing new risks to fragile ecosystems, and the Greenland ice sheet is continuing to send freshwater and ice into the ocean, raising global sea level</p>
<p>In the annual <a href="https://arctic.noaa.gov/Report-Card/Report-Card-2022">Arctic Report Card</a>, released Dec. 13, 2022, we brought together 144 other Arctic scientists from 11 countries to examine the current state of the Arctic system.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/500559/original/file-20221212-1585-avllq2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/500559/original/file-20221212-1585-avllq2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/500559/original/file-20221212-1585-avllq2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/500559/original/file-20221212-1585-avllq2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/500559/original/file-20221212-1585-avllq2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/500559/original/file-20221212-1585-avllq2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=425&fit=crop&dpr=1 754w, https://images.theconversation.com/files/500559/original/file-20221212-1585-avllq2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=425&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/500559/original/file-20221212-1585-avllq2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=425&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Some of the Arctic headlines of 2022 discussed in the Arctic Report Card.</span>
<span class="attribution"><span class="source">NOAA Climate.gov</span></span>
</figcaption>
</figure>
<h2>The Arctic is getting wetter and rainier</h2>
<p>We found that <a href="https://arctic.noaa.gov/Report-Card/Report-Card-2022/ArtMID/8054/ArticleID/993/Precipitation">Arctic precipitation is on the rise across all seasons</a>, and these seasons are shifting. </p>
<p>Much of this new precipitation is now falling as rain, sometimes during winter and traditionally frozen times of the year. This disrupts daily life for humans, wildlife and plants. </p>
<p>Roads become dangerously icy more often, and communities face greater risk of river flooding events. For Indigenous reindeer herding communities, winter rain can create an impenetrable ice layer that prevents their reindeer from accessing vegetation beneath the snow. </p>
<figure class="align-center ">
<img alt="Map shows significant increases in precipitation across the Arctic in both winter and fall." src="https://images.theconversation.com/files/500588/original/file-20221213-3149-u7oobq.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/500588/original/file-20221213-3149-u7oobq.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=830&fit=crop&dpr=1 600w, https://images.theconversation.com/files/500588/original/file-20221213-3149-u7oobq.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=830&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/500588/original/file-20221213-3149-u7oobq.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=830&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/500588/original/file-20221213-3149-u7oobq.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1043&fit=crop&dpr=1 754w, https://images.theconversation.com/files/500588/original/file-20221213-3149-u7oobq.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1043&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/500588/original/file-20221213-3149-u7oobq.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1043&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
<span class="attribution"><a class="source" href="https://www.arctic.noaa.gov/Report-Card">NOAA Climate.gov</a></span>
</figcaption>
</figure>
<p>Arctic-wide, this shift toward wetter conditions can disrupt the lives of animals and plants that have evolved for dry and cold conditions, potentially altering Arctic peoples’ local foods.</p>
<p>When Fairbanks, Alaska, got 1.4 inches of freezing rain in December 2021, the moisture created an ice layer that persisted for months, bringing down trees and disrupting travel, infrastructure and the ability of some Arctic animals to forage for food. The resulting ice layer was largely <a href="https://www.ktoo.org/2022/12/06/one-third-delta-junction-bison-starve/">responsible for the deaths of a third of a bison herd</a> in interior Alaska.</p>
<p>There are multiple reasons for this increase in Arctic precipitation.</p>
<p>As sea ice rapidly declines, more open water is exposed, which feeds increased moisture into the atmosphere. The entire Arctic region has seen a more than <a href="https://arctic.noaa.gov/Report-Card/Report-Card-2022/ArtMID/8054/ArticleID/989/Sea-Ice">40% loss in summer sea ice extent</a> over the 44-year satellite record.</p>
<p>The Arctic atmosphere is also warming <a href="https://arctic.noaa.gov/Report-Card/Report-Card-2022/ArtMID/8054/ArticleID/992/Surface-Air-Temperature">more than twice as fast as the rest of the globe</a>, and this warmer air can hold more moisture. </p>
<figure class="align-center ">
<img alt="Map and time series chart show the continuing decline of the maximum extent of Arctic sea ice." src="https://images.theconversation.com/files/500769/original/file-20221213-15012-yusnzh.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/500769/original/file-20221213-15012-yusnzh.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=983&fit=crop&dpr=1 600w, https://images.theconversation.com/files/500769/original/file-20221213-15012-yusnzh.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=983&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/500769/original/file-20221213-15012-yusnzh.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=983&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/500769/original/file-20221213-15012-yusnzh.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1235&fit=crop&dpr=1 754w, https://images.theconversation.com/files/500769/original/file-20221213-15012-yusnzh.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1235&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/500769/original/file-20221213-15012-yusnzh.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1235&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
<span class="attribution"><a class="source" href="https://www.arctic.noaa.gov/Report-Card">NOAA Climate.gov</a></span>
</figcaption>
</figure>
<p>Under the ground, the wetter, rainier Arctic is accelerating the <a href="https://theconversation.com/thawing-permafrost-is-roiling-the-arctic-landscape-driven-by-a-hidden-world-of-changes-beneath-the-surface-as-the-climate-warms-174157">thaw of permafrost</a>, upon which most Arctic communities and infrastructure are built. The result is crumbling buildings, sagging and cracked roads, the emergence of sinkholes and the collapse of community coastlines along rivers and ocean. </p>
<p>Wetter weather also disrupts the building of a reliable winter snowpack and safe, reliable river ice, and often challenges Indigenous communities’ efforts to <a href="https://arctic.noaa.gov/Report-Card/Report-Card-2019/ArtMID/7916/ArticleID/850/Voices-from-the-Front-Lines-of-a-Changing-Bering-Sea">harvest and secure their food</a>.</p>
<p>When <a href="https://theconversation.com/typhoon-merbok-fueled-by-unusually-warm-pacific-ocean-pounded-alaskas-vulnerable-coastal-communities-at-a-critical-time-190898">Typhoon Merbok</a> hit in September 2022, fueled by unusually warm Pacific water, its hurricane-force winds, 50-foot waves and far-reaching storm surge damaged homes and infrastructure over 1,000 miles of Bering Sea coastline, and disrupted hunting and harvesting at a crucial time.</p>
<figure class="align-center ">
<img alt="Globe and time series chart show temperatures rising faster across the Arctic than in the rest of the world." src="https://images.theconversation.com/files/500589/original/file-20221213-900-rbisur.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/500589/original/file-20221213-900-rbisur.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=774&fit=crop&dpr=1 600w, https://images.theconversation.com/files/500589/original/file-20221213-900-rbisur.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=774&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/500589/original/file-20221213-900-rbisur.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=774&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/500589/original/file-20221213-900-rbisur.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=972&fit=crop&dpr=1 754w, https://images.theconversation.com/files/500589/original/file-20221213-900-rbisur.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=972&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/500589/original/file-20221213-900-rbisur.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=972&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
<span class="attribution"><a class="source" href="https://www.arctic.noaa.gov/Report-Card">NOAA Climate.gov</a></span>
</figcaption>
</figure>
<h2>Arctic snow season is shrinking</h2>
<p>Snow plays critical roles in the Arctic, and the snow season is shrinking.</p>
<p>Snow helps to keep the Arctic cool by reflecting incoming solar radiation back to space, rather than allowing it to be absorbed by the darker snow-free ground. Its presence helps <a href="https://arctic.noaa.gov/Report-Card/Report-Card-2022/ArtMID/8054/ArticleID/1002/Lake-Ice">lake ice last longer into spring</a> and helps the land to retain moisture longer into summer, preventing overly dry conditions that are ripe for <a href="https://uaf-iarc.org/2022/12/a-future-of-more-wildfires-in-alaska/">devastating wildfires</a>.</p>
<p>Snow is also a travel platform for hunters and a habitat for many animals that rely on it for nesting and protection from predators.</p>
<p>A <a href="https://arctic.noaa.gov/Report-Card/Report-Card-2022/ArtMID/8054/ArticleID/991/Terrestrial-Snow-Cover">shrinking snow season</a> is disrupting these critical functions. For example, the June snow cover extent across the Arctic is declining at a rate of nearly 20% per decade, marking a dramatic shift in how the snow season is defined and experienced across the North. </p>
<p>Even in the depth of winter, warmer temperatures are breaking through. The far northern Alaska town of Utqiaġvik hit 40 degrees Fahrenheit (4.4 C) – <a href="https://www.washingtonpost.com/weather/2022/12/06/alaska-winter-temperature-record-utqiagvik/">8 F above freezing</a> – on Dec. 5, 2022, even though the sun does not breach the horizon from mid-November through mid-January.</p>
<figure class="align-center ">
<img alt="Map and time series chart show how June snowfall has decreased since the late 1970s." src="https://images.theconversation.com/files/500590/original/file-20221213-22-drdove.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/500590/original/file-20221213-22-drdove.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=863&fit=crop&dpr=1 600w, https://images.theconversation.com/files/500590/original/file-20221213-22-drdove.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=863&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/500590/original/file-20221213-22-drdove.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=863&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/500590/original/file-20221213-22-drdove.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1085&fit=crop&dpr=1 754w, https://images.theconversation.com/files/500590/original/file-20221213-22-drdove.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1085&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/500590/original/file-20221213-22-drdove.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1085&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
<span class="attribution"><a class="source" href="https://www.arctic.noaa.gov/Report-Card">NOAA Climate.gov</a></span>
</figcaption>
</figure>
<p>Fatal falls through thin sea, lake and river ice are <a href="https://doi.org/10.1093/pubmed/fdt081">on the rise</a> across Alaska, resulting in immediate tragedies as well as adding to the <a href="https://arctic.noaa.gov/Report-Card/Report-Card-2022/ArtMID/8054/ArticleID/1001/Consequences-of-Rapid-Environmental-Arctic-Change-for-People">cumulative human cost of climate change</a> that Arctic Indigenous peoples are now experiencing on a generational scale.</p>
<h2>Greenland ice melt means global problems</h2>
<p>The impacts of Arctic warming are not limited to the Arctic. In 2022, the <a href="https://arctic.noaa.gov/Report-Card/Report-Card-2022/ArtMID/8054/ArticleID/990/Greenland-Ice-Sheet">Greenland ice sheet lost ice for the 25th consecutive year</a>. This adds to rising seas, which escalates the danger coastal communities around the world must plan for to mitigate flooding and storm surge.</p>
<p>In early September 2022, the Greenland ice sheet experienced an <a href="https://arctic.noaa.gov/Report-Card/Report-Card-2022/ArtMID/8054/ArticleID/990/Greenland-Ice-Sheet">unprecedented late-season melt event across 36% of the ice sheet surface</a>. This was followed by another, even later melt event that same month, caused by the remnants of Hurricane Fiona moving up along eastern North America.</p>
<p>International <a href="https://omg.jpl.nasa.gov/portal/">teams of scientists</a> are dedicated to assessing the scale to which the Greenland ice sheet’s ice formation and ice loss are out of balance. They are also increasingly learning about the transformative role that warming ocean waters play.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/500374/original/file-20221212-105279-65pkn0.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/500374/original/file-20221212-105279-65pkn0.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/500374/original/file-20221212-105279-65pkn0.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/500374/original/file-20221212-105279-65pkn0.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/500374/original/file-20221212-105279-65pkn0.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/500374/original/file-20221212-105279-65pkn0.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=425&fit=crop&dpr=1 754w, https://images.theconversation.com/files/500374/original/file-20221212-105279-65pkn0.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=425&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/500374/original/file-20221212-105279-65pkn0.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=425&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">NOAA Climate.gov</span></span>
</figcaption>
</figure>
<p>This year’s Arctic Report Card includes <a href="https://arctic.noaa.gov/Report-Card/Report-Card-2022/ArtMID/8054/ArticleID/1007/Lessons-From-Oceans-Melting-Greenland-a-NASA-Airborne-Mission">findings from the NASA Oceans Melting Greenland (OMG) mission</a> that has confirmed that warming ocean temperatures are increasing ice loss at the edges of the ice sheet.</p>
<h2>Human-caused change is reshaping the Arctic</h2>
<p>We are living in a new geological age — <a href="https://nap.nationalacademies.org/catalog/18726/the-arctic-in-the-anthropocene-emerging-research-questions">the Anthropocene</a> — in which human activity is the dominant influence on our climate and environments.</p>
<p>In the warming Arctic, this requires decision-makers to better anticipate the interplay between a changing climate and human activity. For example, satellite-based ship data since 2009 clearly show that <a href="https://arctic.noaa.gov/Report-Card/Report-Card-2022/ArtMID/8054/ArticleID/1004/Satellite-Record-of-Pan-Arctic-Maritime-Ship-Traffic">maritime ship traffic</a> has increased within all Arctic high seas and national exclusive economic zones as the region has warmed.</p>
<figure class="align-center ">
<img alt="Map shows increase in ship traffic in Arctic regions since 2009, with a nearly 50% increase in shipping around Norway and over 12% increase near Russia. Paired with a photo of a ship in sea ice." src="https://images.theconversation.com/files/500591/original/file-20221213-23-cximvx.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/500591/original/file-20221213-23-cximvx.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=805&fit=crop&dpr=1 600w, https://images.theconversation.com/files/500591/original/file-20221213-23-cximvx.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=805&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/500591/original/file-20221213-23-cximvx.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=805&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/500591/original/file-20221213-23-cximvx.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1012&fit=crop&dpr=1 754w, https://images.theconversation.com/files/500591/original/file-20221213-23-cximvx.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1012&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/500591/original/file-20221213-23-cximvx.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1012&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
<span class="attribution"><a class="source" href="https://www.arctic.noaa.gov/Report-Card">NOAA Climate.gov</a></span>
</figcaption>
</figure>
<p>For these ecologically sensitive waters, this added ship traffic raises urgent concerns ranging from the future of Arctic trade routes to the introduction of even more human-caused stresses on Arctic peoples, ecosystems and the climate. These concerns are especially pronounced given uncertainties regarding the current geopolitical tensions between Russia and the other Arctic states over its war in Ukraine.</p>
<p>Rapid Arctic warming requires new forms of partnership and information sharing, including <a href="https://arctic.noaa.gov/Report-Card/Report-Card-2022/ArtMID/8054/ArticleID/1001/Consequences-of-Rapid-Environmental-Arctic-Change-for-People">between scientists and Indigenous knowledge-holders</a>. Cooperation and building resilience can help to reduce some risks, but global action to rein in greenhouse gas pollution is essential for the entire planet.</p><img src="https://counter.theconversation.com/content/196254/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Matthew Druckenmiller receives research funding from the National Science Foundation (NSF) and the National Oceanic and Atmospheric Administration (NOAA). </span></em></p><p class="fine-print"><em><span>Rick Thoman receives funding from NOAA/Arctic Program</span></em></p><p class="fine-print"><em><span>Twila Moon receives research funding from the National Science Foundation (NSF) and the National Oceanic and Atmospheric Administration (NOAA).</span></em></p>The annual report is also a reminder that what happens in the Arctic affects the rest of the world.Matthew L. Druckenmiller, Research Scientist, National Snow and Ice Data Center (NSIDC), Cooperative Institute for Research in Environmental Sciences (CIRES), University of Colorado BoulderRick Thoman, Alaska Climate Specialist, University of Alaska FairbanksTwila A. Moon, Deputy Lead Scientist, National Snow and Ice Data Center (NSIDC), Cooperative Institute for Research in Environmental Sciences (CIRES), University of Colorado BoulderLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1655612021-08-06T13:51:47Z2021-08-06T13:51:47ZRecord-breaking winter winds have blown old Arctic sea ice into the melt zone<figure><img src="https://images.theconversation.com/files/415003/original/file-20210806-23-11onvmd.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C4368%2C2903&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/global-warming-arctic-north-pole-svalbard-167348594">Avatar_023/Shutterstock</a></span></figcaption></figure><p>An unusual pattern of winds drove old Arctic sea ice into a precarious position in the winter of 2020. Now in warming waters, large swathes of the Arctic’s diminishing store of old ice lie at risk of melting. But how did this happen, and why is old ice so important?</p>
<p>When winter’s darkness falls on the Arctic Ocean, temperatures plunge to below -30°C. Existing floating ice thickens as the seawater below freezes, and the ice advances into areas that were previously open water. In summer, when temperatures rise and the sun shines for months at a time, the ice thins and retreats. Each September, scientists wait and watch for the annual minimum coverage of Arctic sea ice – a useful indicator for how fast the region is changing. </p>
<p>Ice that survives the summer melt season endures for another winter. Some ice even survives several summers before finally melting. This happens particularly in the colder regions near the North Pole. Ice that survives the summer is known as perennial ice; battle-scarred from its ordeal, it ends up thicker, rougher and more resilient. It’s an important part of the climate and ecology of the Arctic and it’s disappearing due to global heating.</p>
<figure class="align-center ">
<img alt="A polar bear walks on sea ice" src="https://images.theconversation.com/files/414905/original/file-20210805-27-12eepv8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/414905/original/file-20210805-27-12eepv8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/414905/original/file-20210805-27-12eepv8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/414905/original/file-20210805-27-12eepv8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/414905/original/file-20210805-27-12eepv8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/414905/original/file-20210805-27-12eepv8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/414905/original/file-20210805-27-12eepv8.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 Arctic sea ice is hunting territory for polar bears.</span>
<span class="attribution"><span class="source">Stefan Hendricks, Alfred Wegener Institute</span></span>
</figcaption>
</figure>
<p>When sunlight hits the Earth, it’s either reflected or absorbed. Reflected light bounces back into outer space, whereas absorbed light heats the planet. Sea ice covered in snow reflects up to <a href="https://nsidc.org/cryosphere/seaice/processes/albedo.html#:%7E:text=Sea%20ice%20has%20a%20much,from%20approximately%200.5%20to%200.7.">90% of incoming sunlight</a>, making it a powerful defence against global warming. But as polar sea ice melts due to climate change, sunlight increasingly hits the ocean, where over <a href="https://nsidc.org/cryosphere/seaice/processes/albedo.html#:%7E:text=Sea%20ice%20has%20a%20much,from%20approximately%200.5%20to%200.7.">90% is absorbed</a>. </p>
<p>Perennial ice is particularly important because it’s more capable of surviving the summer and shielding the Arctic Ocean from the sun and keeping the region cool. But every year the ice melt season lengthens and the growth season shortens. And both seasons in the Arctic are getting hotter. These factors conspire against perennial ice, and less has been surviving the melt season every year. </p>
<h2>Why was winter 2020-2021 so exceptional?</h2>
<p>To maintain a healthy perennial ice cover in the Arctic, it’s critical that the ice stays out of warm waters where it might melt in summer. Sea ice moves around the Arctic Ocean as it gets blown by the wind. If it stays in the cold regions, where ice can survive the summer, it has a good shot at becoming perennial ice. If the winds blow it southward into warmer waters, its chances of survival drop dramatically. </p>
<p>In February 2021, my academic colleagues and I <a href="https://www.nature.com/articles/s43247-021-00221-8">observed</a> a startling weather phenomenon in the Arctic. The polar vortex, <a href="https://www.climate.gov/news-features/understanding-climate/understanding-arctic-polar-vortex#:%7E:text=The%20Arctic%20polar%20vortex%20is,Hemisphere%20stratosphere%20in%20its%20winter.">a ring of anticlockwise-flowing wind</a> that holds a pool of extremely cold air over the Arctic, collapsed, resulting in a new record for the region’s highest surface air pressure. Cold weather then moved southwards at the surface, causing UK temperatures to fall to their <a href="https://www.theguardian.com/uk-news/2021/feb/11/uk-temperature-falls-lowest-level-decade-extreme-freeze">lowest level since 1995</a>. In Texas, extremely cold weather paralysed the power grid, leaving four million people <a href="https://www.carbonbrief.org/media-reaction-texas-deep-freeze-power-blackouts-and-the-role-of-global-warming">without power</a>. </p>
<p>In the Arctic, the breakdown of the polar vortex produced an exceptional pattern of surface winds that swirled clockwise about the centre of the Arctic Ocean like water around a plughole. These swirling winds spun the floating icepack like a spinning top. In doing so, they drove the Arctic’s perennial ice from a relatively safe and cold position north of Greenland into an area where ice increasingly can’t survive the summer: the Beaufort Sea. </p>
<p>Over the winter, the Beaufort Sea filled with perennial ice such that in the last week of February 2021, it contained a record fraction (23.5%) of the Arctic Ocean’s total perennial ice cover. This is where things get really interesting. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/414901/original/file-20210805-27-krqgx3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A graph showing perennial ice cover in the 26th week of the year since 1984." src="https://images.theconversation.com/files/414901/original/file-20210805-27-krqgx3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/414901/original/file-20210805-27-krqgx3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=390&fit=crop&dpr=1 600w, https://images.theconversation.com/files/414901/original/file-20210805-27-krqgx3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=390&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/414901/original/file-20210805-27-krqgx3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=390&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/414901/original/file-20210805-27-krqgx3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=491&fit=crop&dpr=1 754w, https://images.theconversation.com/files/414901/original/file-20210805-27-krqgx3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=491&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/414901/original/file-20210805-27-krqgx3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=491&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">At 1.76 million square kilometres, perennial ice cover mid-year was lowest in 2021.</span>
<span class="attribution"><span class="source">Robbie Mallett</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Perennial ice is, in theory, resistant to melting in summer. It’s thicker, and generally has a deeper cover of protective snow on top. By positioning robust ice in an area where ice typically melts, scientists may record more ice coverage come the September minimum. But this will come at the cost of the perennial ice cover itself which, while robust, is more precarious than ever in a melt-prone region. </p>
<p>This highlights the fact that there is no single barometer for the health of Arctic sea ice. The coverage at the September minimum is important (and highly publicised) but so is the coverage of thicker, more robust perennial ice. These two metrics will probably tell different stories in September.</p>
<p>So what does the future look like for the Arctic’s old ice? As the region continues to warm at <a href="https://oaarchive.arctic-council.org/bitstream/handle/11374/2621/MMIS12_2021_REYKJAVIK_AMAP_Arctic-Climate-Change-Update-2021-Key-Trends-and-Impacts.-Summary-for-Policy-makers.pdf?sequence=1&isAllowed=y">three times</a> the global average, less and less of the ocean will become survivable for ice in summer. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/414909/original/file-20210805-17-171wplo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A line graph depicting perennial ice area with 2021 being the lowest line." src="https://images.theconversation.com/files/414909/original/file-20210805-17-171wplo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/414909/original/file-20210805-17-171wplo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=397&fit=crop&dpr=1 600w, https://images.theconversation.com/files/414909/original/file-20210805-17-171wplo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=397&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/414909/original/file-20210805-17-171wplo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=397&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/414909/original/file-20210805-17-171wplo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=499&fit=crop&dpr=1 754w, https://images.theconversation.com/files/414909/original/file-20210805-17-171wplo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=499&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/414909/original/file-20210805-17-171wplo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=499&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 perennial ice area in the Arctic has changed each year since 1984.</span>
<span class="attribution"><span class="source">Robbie Mallett</span></span>
</figcaption>
</figure>
<p>Recent research using the newest generation of climate models projects that the coverage of sea ice at the September minimum will fall to conditions recognised as “ice free” <a href="https://www.nature.com/articles/s43247-021-00214-7">around 2035</a>. Since the beginning of the satellite record in 1984, the coverage of perennial ice <a href="https://iopscience.iop.org/article/10.1088/1748-9326/aade56">has roughly halved</a>, and this downward trend will continue. </p>
<p>In the last week of February 2021, the coverage of perennial ice was the second lowest on record, behind 2013. At the time of writing, using the most recent data, the perennial ice coverage has decreased substantially and now sits at the lowest level on record – its precarious positioning since winter has likely played a role. With more than a month remaining of the melt season before the September minimum, there’s lots still to play for. But it’s likely that 2021 will set a new record for the lowest perennial ice cover.</p><img src="https://counter.theconversation.com/content/165561/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Robbie Mallett receives funding through the London NERC DTP.</span></em></p>A particularly stormy winter has pushed perennial sea ice into the Arctic melt zone.Robbie Mallett, PhD Candidate, London NERC DTP & Centre for Polar Observation and Modelling, UCLLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1441062020-09-18T09:01:48Z2020-09-18T09:01:48ZArctic sea ice is being increasingly melted from below by warming Atlantic water<figure><img src="https://images.theconversation.com/files/358518/original/file-20200917-24-pt6k5m.jpg?ixlib=rb-1.1.0&rect=689%2C224%2C5052%2C2483&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Denis Burdin / shutterstock</span></span></figcaption></figure><p>Each September, scientists like me look out for the point when the Arctic’s meagre summer fizzles out and sea ice begins to grow once more. This point is known as the annual sea ice minimum extent. It has declined consistently over the past 15 years, and 2019 was the second lowest after 2012 in 42 years of continuous satellite records. This year’s minimum is imminent, and there is already <a href="http://nsidc.org/arcticseaicenews/2020/09/suddenly-in-second-place/">even less ice</a> coverage than last year.</p>
<p>What’s causing this decline in minimum sea ice extent? The short answer is our changing climate. But the more specific answer is that Arctic sea ice is increasingly being thinned not just by warm air from above but by ever-warmer waters from below.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/358671/original/file-20200917-18-1grv4kd.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Map showing Arctic sea ice extent, September 16, 2020." src="https://images.theconversation.com/files/358671/original/file-20200917-18-1grv4kd.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/358671/original/file-20200917-18-1grv4kd.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=714&fit=crop&dpr=1 600w, https://images.theconversation.com/files/358671/original/file-20200917-18-1grv4kd.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=714&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/358671/original/file-20200917-18-1grv4kd.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=714&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/358671/original/file-20200917-18-1grv4kd.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=898&fit=crop&dpr=1 754w, https://images.theconversation.com/files/358671/original/file-20200917-18-1grv4kd.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=898&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/358671/original/file-20200917-18-1grv4kd.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=898&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Arctic sea ice today (white) is covering a much smaller area than in 1980-2010 (orange line).</span>
<span class="attribution"><a class="source" href="http://nsidc.org/arcticseaicenews/">National Snow and Ice Data Center, University of Colorado, Boulder</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>In fact, in a recently published <a href="https://journals.ametsoc.org/jcli/article/doi/10.1175/JCLI-D-19-0976.1/353233/Weakening-of-cold-halocline-layer-exposes-sea-ice">scientific study</a> my colleagues and I looked at why sea ice was melting in the eastern Arctic Ocean and showed that the influence of heat from the interior of the ocean has now overtaken the influence of the atmosphere. </p>
<p>While atmospheric heat is the dominant reason for melting in the summer, it has little influence during the cold dark polar winter. However, the ocean warms the ice from below year-round. Our new research shows that this influence has more than doubled over the past decade or so, and is now equivalent to the melting of nearly a metre thickness of sea ice each year (For comparison, at the North Pole the ocean is usually only covered by a couple metres of ice). </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/358678/original/file-20200917-24-b9d7w8.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Graph showing monthly arctic sea ice extent in 2012, 2020 and average 1981-2010." src="https://images.theconversation.com/files/358678/original/file-20200917-24-b9d7w8.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/358678/original/file-20200917-24-b9d7w8.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=480&fit=crop&dpr=1 600w, https://images.theconversation.com/files/358678/original/file-20200917-24-b9d7w8.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=480&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/358678/original/file-20200917-24-b9d7w8.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=480&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/358678/original/file-20200917-24-b9d7w8.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=603&fit=crop&dpr=1 754w, https://images.theconversation.com/files/358678/original/file-20200917-24-b9d7w8.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=603&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/358678/original/file-20200917-24-b9d7w8.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=603&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">2020 will have the least Arctic sea ice ever – aside from 2012.</span>
<span class="attribution"><span class="source">National Snow and Ice Data Center, University of Colorado, Boulder</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>This warm water, sometimes referred to as the “<a href="https://www.sciencemag.org/news/2020/08/growing-underwater-heat-blob-speeds-demise-arctic-sea-ice">heat blob</a>”, originates in the Atlantic and heads northwards via an extension of the Gulf Stream, entering the Arctic Ocean around Svalbard, an archipelago halfway between Norway and the North Pole. The blob has already resulted in the disappearance of winter sea ice off the <a href="https://theconversation.com/extreme-weather-in-europe-linked-to-less-sea-ice-and-warming-in-the-barents-sea-100628">northern coast of Norway and north-west Russia</a>. </p>
<p>Further to the east, this warm water has been isolated from the sea surface, and so sea ice, by a layer of colder, fresher water. However, as the heat blob is getting warmer and moving closer to the surface its influence is now <a href="https://theconversation.com/heat-from-the-atlantic-ocean-is-melting-arctic-sea-ice-further-eastwards-than-ever-before-76108">spreading eastwards through the Arctic</a>.</p>
<p>In a <a href="https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2020GL089469">second scientific paper</a> we showed that currents in the upper Arctic ocean were increasing which, when combined with declining sea ice and the weakening of the boundaries between layers of warm and cold water, was potentially stirring more warm water from the heat blob towards the surface. The combined impact is a new back and forth relationship between sea ice and ocean heat which could lead to a new ocean climate state in the eastern Arctic Ocean.</p>
<p>All this may be feeding into ever more extreme climate change in the Arctic. Throughout summer 2020 the <a href="https://theconversation.com/siberia-heatwave-why-the-arctic-is-warming-so-much-faster-than-the-rest-of-the-world-141455">Siberian heatwave</a> continually shattered temperature records, including eastern Arctic sea surface temperatures. And while sea ice reflects much of the sun’s rays back into space, open water is dark and absorbs the sun’s heat. So as the sea ice retreated the surface water is warmed, which in turned further warms the atmosphere above, quite apart from the influence of increasing greenhouse gases. </p>
<p>There is still much more to learn about the link between the eastwards spread of the influence of Atlantic heat, and the reduction in sea ice it brings, and knock on effects on severe weather at lower latitudes. But it is clear that the Arctic – already warming faster than anywhere else on Earth – could be in the process of transitioning to a “new” state.</p><img src="https://counter.theconversation.com/content/144106/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Tom Rippeth receives funding from RCUK NERC. He is a member of the Liberal Democrats and leads STAMP, the campaign against a new road scheme in North Wales.</span></em></p>Scientists find oceanic heat has overtaken atmospheric heat as the main cause of melting.Tom Rippeth, Professor of Physical Oceanography, Bangor UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1211052019-10-01T03:16:02Z2019-10-01T03:16:02ZWinter storms are speeding up the loss of Arctic sea ice<figure><img src="https://images.theconversation.com/files/285985/original/file-20190729-43136-nyvg1d.JPG?ixlib=rb-1.1.0&rect=0%2C489%2C4608%2C2269&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A scientist checks cracks in the Arctic sea ice after a storm (April 2015, N-ICE2015 expedition).</span> <span class="attribution"><span class="source">Amelie Meyer/NPI</span>, <span class="license">Author provided</span></span></figcaption></figure><p>Arctic sea ice is <a href="https://climate.nasa.gov/vital-signs/arctic-sea-ice/">already disappearing rapidly</a> but <a href="https://www.nature.com/articles/s41598-019-45574-5">our research</a> shows winter storms are now further accelerating sea ice loss.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/arctic-breakdown-what-climate-change-in-the-far-north-means-for-the-rest-of-us-123309">Arctic breakdown: what climate change in the far north means for the rest of us</a>
</strong>
</em>
</p>
<hr>
<p>The research is based on data we gathered during an <a href="https://www.npolar.no/en/projects/n-ice2015/">expedition</a> on a small Norwegian research vessel, <a href="https://www.bbc.com/news/av/science-environment-32548915/tour-of-norwegian-arctic-science-ship-lance">the Lance</a>, that was left to drift in the Arctic sea ice for five months in 2015.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/286169/original/file-20190730-43130-1lt6ezn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/286169/original/file-20190730-43130-1lt6ezn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/286169/original/file-20190730-43130-1lt6ezn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/286169/original/file-20190730-43130-1lt6ezn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/286169/original/file-20190730-43130-1lt6ezn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/286169/original/file-20190730-43130-1lt6ezn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/286169/original/file-20190730-43130-1lt6ezn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/286169/original/file-20190730-43130-1lt6ezn.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"></a>
<figcaption>
<span class="caption">Time series of air temperature anomalies in the Arctic for the period 1981-2010: Temperatures in the Arctic in May and June 2019 period were the warmest in the satellite records.</span>
<span class="attribution"><span class="source">Zack Labe (@ZLabe)</span></span>
</figcaption>
</figure>
<p>The expedition was intense and felt more like going to the Moon than going on a typical research cruise. What took us by surprise were the many winter storms that battered the ice (and our ship and ice camp).</p>
<p>It has taken us years to collate these data but now we know the winter storms play a key role in the fate of Arctic sea ice, particularly in the Atlantic sector of the Arctic.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/286170/original/file-20190730-43126-d6zn05.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/286170/original/file-20190730-43126-d6zn05.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=300&fit=crop&dpr=1 600w, https://images.theconversation.com/files/286170/original/file-20190730-43126-d6zn05.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=300&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/286170/original/file-20190730-43126-d6zn05.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=300&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/286170/original/file-20190730-43126-d6zn05.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=377&fit=crop&dpr=1 754w, https://images.theconversation.com/files/286170/original/file-20190730-43126-d6zn05.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=377&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/286170/original/file-20190730-43126-d6zn05.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">Norwegian research vessel ‘Lance’ frozen in the Arctic sea ice in February 2015 during the N-ICE2015 expedition.</span>
<span class="attribution"><span class="source">Paul Dodd (NPI)</span></span>
</figcaption>
</figure>
<h1>How winter storms amplify climate change</h1>
<p>On average, <a href="https://www.nature.com/articles/s41598-019-45574-5/figures/1">about 10 extreme storms</a> will reach all the way to the North Pole each winter. While these winter storms are short (they last on average 6-48 hours), they can be incredibly intense. </p>
<p>During a storm in winter 2015 we saw the air temperature rise from -40°C (-40°F) to 0°C (32°F) in just a day, and then fall back to -30°C (-22°F) the next day, when cold Arctic air returned after the storm.</p>
<p>These storms bring heat, moisture and strong winds into the Arctic, and next we look at how they impact sea ice and its surroundings.</p>
<h2>Warming and weakening the ice</h2>
<p>The heat from the storms warms up the air, snow and ice, slowing down the growth of the ice. Moisture from the storms falls as snow on the ice. After the storm, the blanket of snow insulates the ice from the cold air, further slowing the growth of the ice for the remainder of winter.</p>
<p>The strong winds during the storms push the ice around and break it into pieces, making it more fragile and deforming it, more like a boulder field.</p>
<p>The strong winds also stir the ocean below the ice, mixing up warmer water from deeper waters to the surface where it melts the ice from below. This melting of the ice in the middle of winter can happen for several days after the storms when the air is already back to well below freezing.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/286174/original/file-20190730-43114-1qcjeuo.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/286174/original/file-20190730-43114-1qcjeuo.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/286174/original/file-20190730-43114-1qcjeuo.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=351&fit=crop&dpr=1 600w, https://images.theconversation.com/files/286174/original/file-20190730-43114-1qcjeuo.PNG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=351&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/286174/original/file-20190730-43114-1qcjeuo.PNG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=351&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/286174/original/file-20190730-43114-1qcjeuo.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=441&fit=crop&dpr=1 754w, https://images.theconversation.com/files/286174/original/file-20190730-43114-1qcjeuo.PNG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=441&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/286174/original/file-20190730-43114-1qcjeuo.PNG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=441&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Processes related to Arctic winter storms. In the first storm phase, strong southerly winds compress the ice cover and transport warm air, moisture, and bring strong winds. In the second phase, northerly winds transport ice southwards. After the storm has passed, cold and calm conditions return, allowing new ice to grow in leads. When the next winter storm arrives, it further drives the ice cover into a relatively thin-ice, snow-covered mosaic of strongly deformed ice floes. These new conditions impact surrounding ecosystems by shaping habitats and light conditions.</span>
<span class="attribution"><span class="source">Graham et al., 2019 (Scientific Reports)</span></span>
</figcaption>
</figure>
<h2>Thinner ice, shelter for life and accelerated melting</h2>
<p>The breakup of the ice opens big passages of open water between ice floes, called leads. In winter these passages end up refreezing rapidly, generating new super-thin ice.</p>
<p>These thinner refrozen patches of ice let more light through in the following spring, allowing ocean plants (phytoplankton) <a href="https://www.nature.com/articles/srep40850" title="Leads in Arctic pack ice enable early phytoplankton blooms below snow-covered sea ice">to bloom earlier</a>.</p>
<p>The rougher sea ice landscape becomes a shelter for many ice-associated Arctic organisms, including ice algae, <a href="https://www.frontiersin.org/articles/10.3389/fmars.2018.00075/full">becoming biological hot spots</a> in the following spring.</p>
<p>The broken up and deformed ice drifts faster, reaching warmer waters where it melts sooner and faster.</p>
<p>So really, winter storms precondition the ice to a faster melt in the following spring with an impact that continues well into the following season.</p>
<h1>Why is Arctic sea ice declining?</h1>
<p>Winter <a href="https://nsidc.org/cryosphere/seaice/index.html">sea ice</a> cover in the Atlantic sector of the Arctic <a href="https://doi.org/10.1175/JCLI-D-17-0427.1" title="Seasonal and Regional Manifestation of Arctic Sea Ice Loss">has been retreating at a record breaking pace</a>, especially in the Barents Sea off Norway and Russia.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/286171/original/file-20190730-43149-1fdc9jc.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/286171/original/file-20190730-43149-1fdc9jc.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/286171/original/file-20190730-43149-1fdc9jc.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=464&fit=crop&dpr=1 600w, https://images.theconversation.com/files/286171/original/file-20190730-43149-1fdc9jc.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=464&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/286171/original/file-20190730-43149-1fdc9jc.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=464&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/286171/original/file-20190730-43149-1fdc9jc.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=583&fit=crop&dpr=1 754w, https://images.theconversation.com/files/286171/original/file-20190730-43149-1fdc9jc.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=583&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/286171/original/file-20190730-43149-1fdc9jc.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=583&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Average September Arctic sea ice extent from 1979 to 2018. Black line shows monthly average for each year; blue line shows the trend.</span>
<span class="attribution"><a class="source" href="https://www.arcus.org/sipn/sea-ice-outlook/2018/post-season">National Snow and Ice Data Center</a></span>
</figcaption>
</figure>
<p>The Arctic is particularly <a href="https://www.pmel.noaa.gov/arctic-zone/essay_serreze.html" title="Why is the Arctic So Sensitive to Climate Change and Why Do We Care?">sensitive to human driven climate change</a>. We know the decrease in sea ice is due to both the warming of the Arctic (<a href="https://www.pmel.noaa.gov/arctic-zone/essay_walsh.html" title="What long term trends and decadal changes do you see occurring in the Arctic atmosphere, and what significance do they have?">air</a> and <a href="https://www.nationalgeographic.com/environment/2019/01/oceans-warming-faster-than-ever/">ocean</a>) and changing wind patterns that break up the ice cover. </p>
<p>But there are also amplifying mechanisms or “feedback” mechanisms, in which one natural process reinforces another. Their role in the decrease of sea ice is hard to predict. We now know winter storms in the Arctic contribute to these feedback mechanisms.</p>
<h1>More storms ahead</h1>
<p>Arctic winter storms are <a href="https://iopscience.iop.org/article/10.1088/1748-9326/aa7def/meta" title="Extreme cyclone events in the Arctic: Wintertime variability and trends">increasing in frequency</a> and this is likely due to climate change. </p>
<p>With the thinner Arctic sea ice cover and shallower warmer water in the Arctic Ocean, the mechanisms we observed during the winter storms will likely strengthen and the overall impact of winter storms on Arctic ice is likely to increase in the future. </p>
<p>Two weeks ago, the <a href="https://nsidc.org/arcticseaicenews/2019/09/arctic-sea-ice-reaches-second-lowest-minimum-in-satellite-record/">Arctic sea ice reached its minimum extent for 2019</a>, after another winter of intense winter storms. The minimum ice extent was effectively tied for second lowest since modern record-keeping began in the late 1970s, along with 2007 and 2016, reinforcing the long-term downward trend in Arctic ice extent. Arctic sea ice has been declining for at least 40 years, and amplifying mechanisms such as the winter storms are accelerating this retreat.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/294494/original/file-20190927-185390-194ri0y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/294494/original/file-20190927-185390-194ri0y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/294494/original/file-20190927-185390-194ri0y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/294494/original/file-20190927-185390-194ri0y.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/294494/original/file-20190927-185390-194ri0y.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/294494/original/file-20190927-185390-194ri0y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/294494/original/file-20190927-185390-194ri0y.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/294494/original/file-20190927-185390-194ri0y.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"></a>
<figcaption>
<span class="caption">Arctic sea ice extent just reached its annual minimum extent for 2019 on September 18. This season was a tie for the <em>2nd lowest</em> on record, along with 2007 and 2016 and behind 2012, which holds the overall record minimum.</span>
<span class="attribution"><span class="source">Zack Labe (@ZLabe)</span></span>
</figcaption>
</figure>
<p>As highlighted in the recent <a href="https://report.ipcc.ch/srocc/pdf/SROCC_SPM_Approved.pdf">IPCC Ocean and Cryopshere report</a>, these changes in September sea ice are likely unprecedented for at least 1,000 years.</p>
<p>Remember also that changes in the Arctic don’t just affect the immediate region: Arctic warming has been linked to the <a href="https://www.carbonbrief.org/qa-how-is-arctic-warming-linked-to-polar-vortext-other-extreme-weather">polar vortex</a>, and weather extremes across <a href="https://www.sciencedaily.com/releases/2019/05/190528140115.htm">central Europe and north America</a>. </p>
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Read more:
<a href="https://theconversation.com/microplastics-may-affect-how-arctic-sea-ice-forms-and-melts-120721">Microplastics may affect how Arctic sea ice forms and melts</a>
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<p>As we start taking into account feedback mechanisms like the winter storms, <a href="https://phys.org/news/2019-07-paris-agreement-ice-free-arctic.html">our predictions for the first Arctic sea ice free summer</a> are indicating it will likely happen before 2050.</p><img src="https://counter.theconversation.com/content/121105/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Amelie Meyer has received funding from the Norwegian Polar Institutes Centre for Ice, Climate and Ecosystems (ICE) and currently receives funding from the ARC Centre of Excellence for Climate Extremes. Amelie Meyer is affiliated with the ARC Centre of Excellence for Climate Extremes, IMAS, University of Tasmania, Hobart, Australia. </span></em></p><p class="fine-print"><em><span>Mats Granskog receives funding from the Norwegian Polar Institute. This work was supported by the Centre for Ice, Climate and Ecosystems (ICE) at the Norwegian Polar Institute. </span></em></p>Warm summers aren’t the only threat to Arctic ice – increasingly intense winter storms are also weakening and reducing ice cover.Amelie Meyer, Research fellow, University of TasmaniaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1220102019-08-17T13:10:15Z2019-08-17T13:10:15ZBefore Trump eyed Greenland: Here’s what happened last time the US bought a large chunk of the Arctic<figure><img src="https://images.theconversation.com/files/288395/original/file-20190816-192210-ad408d.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Most of Greenland is covered by Arctic ice. </span> <span class="attribution"><a class="source" href="http://www.apimages.com/metadata/Index/Arctic-Ice/06a0075b4c9f4e2fb2e808f69c281bbe/3/0">AP Photo/John McConnico</a></span></figcaption></figure><p><em>Editor’s note: <a href="https://www.wsj.com/articles/trump-eyes-a-new-real-estate-purchase-greenland-11565904223">Reports</a> that President Donald Trump <a href="https://www.npr.org/2019/08/16/751736055/greenland-says-its-not-for-sale-after-reports-that-trump-wants-to-buy-it">has urged aides</a> to look into buying Greenland make us think of the last time the United States bought a major territory in the Arctic: the purchase of Alaska from Russia in 1867. Two years ago, we asked William L. Iggiagruk Hensley, a visiting professor at the University of Alaska Anchorage, to write about that historic sale.</em> </p>
<p>On March 30, 1867, U.S. Secretary of State William H. Seward and Russian envoy Baron Edouard de Stoeckl <a href="https://www.amazon.com/Purchase-Alaska-SHIELS-Archie/dp/B000T3WCMW">signed the Treaty of Cession</a>. With a stroke of a pen, Tsar Alexander II had ceded Alaska, his country’s last remaining foothold in North America, to the United States for US$7.2 million. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/288397/original/file-20190816-192258-1e8vt61.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/288397/original/file-20190816-192258-1e8vt61.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/288397/original/file-20190816-192258-1e8vt61.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=859&fit=crop&dpr=1 600w, https://images.theconversation.com/files/288397/original/file-20190816-192258-1e8vt61.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=859&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/288397/original/file-20190816-192258-1e8vt61.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=859&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/288397/original/file-20190816-192258-1e8vt61.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1079&fit=crop&dpr=1 754w, https://images.theconversation.com/files/288397/original/file-20190816-192258-1e8vt61.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1079&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/288397/original/file-20190816-192258-1e8vt61.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1079&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Alexander II led Russia when the U.S. purchased Alaska.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Alexander_II_of_Russia#/media/File:Zar_Alexander_II_(cropped).jpg">Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>That sum, amounting to <a href="http://www.in2013dollars.com/1867-dollars-in-2015?amount=7200000">just $125 million</a> in 2019 dollars, brought to an end Russia’s 125-year odyssey in Alaska and its expansion across the treacherous Bering Sea, which at one point extended the Russian Empire as far south as Fort Ross, California, 90 miles from San Francisco Bay. </p>
<p>Today Alaska is <a href="http://247wallst.com/special-report/2016/09/15/americas-richest-and-poorest-states-4/11/">one of the richest U.S. states</a> thanks to its abundance of natural resources, such as petroleum, gold and fish, as well as its vast expanse of pristine wilderness and strategic location as a window on Russia and gateway to the Arctic. </p>
<p>So what prompted Russia to withdraw from its American beachhead? And how did it come to possess it in the first place? </p>
<p>As a descendant of Inupiaq Eskimos, <a href="http://scholarship.law.duke.edu/cgi/viewcontent.cgi?article=1481&context=alr">I have been living and studying</a> this history all my life. </p>
<h2>Russia looks east</h2>
<p>The lust for new lands that brought Russia to Alaska and eventually California began in the 16th century, when the country was a fraction of its current size. </p>
<p>That began to change in 1581, when <a href="https://www.amazon.com/Explorations-Kamchatka-North-Pacific-Scimitar/dp/0295959568">Russia overran</a> a Siberian territory known as the Khanate of Sibir, which was controlled by a descendant of Genghis Khan. This key victory opened up Siberia, and within 60 years the Russians were at the Pacific. </p>
<p>The <a href="https://www.amazon.com/Eastward-Empire-Exploration-Conquest-Frontier/dp/0773501339">Russian advance</a> across Siberia was fueled in part by the lucrative fur trade, a desire to expand the Russian Orthodox Christian faith to the “heathen” populations in the east and the addition of new taxpayers and resources to the empire.</p>
<p>In the early 18th century, Peter the Great – who created Russia’s first Navy – wanted to know how far the Asian landmass extended to the east. The Siberian city of Okhotsk became the staging point for two explorations he ordered. And in 1741, Vitus Bering successfully crossed the strait that bears his name and sighted Mt. Saint Elias, near what is now the village of Yakutat, Alaska.</p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/288398/original/file-20190816-192210-10iv90f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/288398/original/file-20190816-192210-10iv90f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/288398/original/file-20190816-192210-10iv90f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=681&fit=crop&dpr=1 600w, https://images.theconversation.com/files/288398/original/file-20190816-192210-10iv90f.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=681&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/288398/original/file-20190816-192210-10iv90f.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=681&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/288398/original/file-20190816-192210-10iv90f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=856&fit=crop&dpr=1 754w, https://images.theconversation.com/files/288398/original/file-20190816-192210-10iv90f.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=856&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/288398/original/file-20190816-192210-10iv90f.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=856&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A map from before the U.S. purchased Alaska.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Alaska#/media/File:1860-russian-america.jpg">Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Although Bering’s second Kamchatka Expedition brought disaster for him personally when adverse weather on the return journey <a href="http://www.fortross.org/russian-american-company.htm">led to a shipwreck</a> on one of the westernmost Aleutian Islands and his eventual death from scurvy in December 1741, it was an incredible success for Russia. The surviving crew fixed the ship, stocked it full of hundreds of the sea otters, foxes and fur seals that were abundant there and returned to Siberia, impressing Russian fur hunters with their valuable cargo. This prompted something akin to the <a href="https://www.nps.gov/klgo/learn/goldrush.htm">Klondike gold rush</a> that happened 150 years later. </p>
<h2>Challenges emerge</h2>
<p>But maintaining these settlements wasn’t easy. Russians in Alaska – who numbered no more than 800 at their peak – faced the reality of being half a globe away from St. Petersburg, then the capital of the empire, making communications a key problem.</p>
<p>Also, Alaska was too far north to allow for significant agriculture and therefore unfavorable as a place to send large numbers of settlers. So they began exploring lands farther south, at first looking only for people to trade with so they could import the foods that wouldn’t grow in Alaska’s harsh climate. They sent ships to what is now California, established trade relations with the Spaniards there and eventually set up their own settlement at <a href="http://www.fortross.org">Fort Ross</a> in 1812.</p>
<p>Thirty years later, however, the entity set up to handle Russia’s American explorations failed. Not long after, the Russians <a href="https://www.amazon.com/Purchase-Alaska-SHIELS-Archie/dp/B000T3WCMW">began to seriously question</a> whether they could continue their Alaskan colony as well. </p>
<p>The colony was <a href="https://www.amazon.com/Russian-American-Relations-1834-1867-History-Hardcover/dp/1895901065">no longer profitable</a> after the sea otter population was decimated, Alaska was difficult to defend and Russia was short on cash due to the costs of the war in Crimea.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/288399/original/file-20190816-192219-eayk78.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/288399/original/file-20190816-192219-eayk78.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/288399/original/file-20190816-192219-eayk78.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/288399/original/file-20190816-192219-eayk78.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/288399/original/file-20190816-192219-eayk78.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/288399/original/file-20190816-192219-eayk78.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/288399/original/file-20190816-192219-eayk78.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">Alaska possesses significant natural wealth and beauty.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/aerial-photos-images-alaska-665465923?src=9g5SlL4HW0Vy3HYyYEm9MQ-1-29">Russ Heinl/Shutterstock.com</a></span>
</figcaption>
</figure>
<h2>Americans eager for a deal</h2>
<p>The Russians were ready to sell. But what motivated the Americans to buy?</p>
<p>In Alaska, the Americans foresaw a potential for gold, fur and fisheries, as well as more trade with China and Japan. The Americans worried that England might try to establish a presence in the territory, and the acquisition of Alaska – it was believed – would help the U.S. become a Pacific power. And overall the government was in an expansionist mode backed by the then-popular idea of “<a href="http://www.history.com/topics/manifest-destiny">manifest destiny</a>.”</p>
<p>So a deal with incalculable geopolitical consequences was struck, and the Americans got quite a bargain for their $7.2 million. </p>
<p>The U.S. gained about 370 million acres of mostly pristine wilderness – almost a third the size of the European Union – including 220 million acres of what are now federal parks and wildlife refuges. Hundreds of billions of dollars in whale oil, fur, copper, gold, timber, fish, platinum, zinc, lead and petroleum have been produced in Alaska over the years – allowing the state to do without a sales or income tax and give every resident an annual stipend. Alaska still likely has <a href="https://www.bloomberg.com/news/articles/2016-10-05/alaska-oil-known-reserves-may-have-just-grown-80-on-discovery">billions of barrels</a> of oil reserves.</p>
<p>The state is also a key part of the United States defense system, with military bases located in Anchorage and Fairbanks, and it is the country’s only connection to the Arctic, which ensures it <a href="https://fas.org/sgp/crs/misc/R41153.pdf">has a seat at the table</a> as melting glaciers allow the exploration of the region’s significant resources. </p>
<p>Alaska finally became a state in 1959, when President Dwight D. Eisenhower signed the <a href="http://www.akleg.gov/basis/get_documents.asp?session=29&docid=29890">Alaska Statehood Act</a>.</p>
<p><em>This is an updated and shortened version of an <a href="https://theconversation.com/why-russia-gave-up-alaska-americas-gateway-to-the-arctic-74675">article originally published</a> on March 29, 2017.</em></p>
<p>[ <em><a href="https://theconversation.com/us/newsletters?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=expertise">Expertise in your inbox. Sign up for The Conversation’s newsletter and get a digest of academic takes on today’s news, every day.</a></em> ]</p><img src="https://counter.theconversation.com/content/122010/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>William L. Iggiagruk Hensley 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>In 1867, the US bought Alaska from Tsar Alexander II for a tidy sum of $7.2 million. Trump probably wouldn’t be able to get that kind of bargain for Greenland.William L. Iggiagruk Hensley, Visiting Distinguished Professor, University of Alaska AnchorageLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1193072019-07-02T19:47:41Z2019-07-02T19:47:41ZTime will tell if this is a record summer for Greenland ice melt, but the pattern over the past 20 years is clear<figure><img src="https://images.theconversation.com/files/281903/original/file-20190630-94684-avcnv7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Melting on top of sea ice off northwestern Greenland, June 2019.</span> <span class="attribution"><a class="source" href="https://twitter.com/RasmusTonboe/status/1139504201615237120">Steffen M. Olsen/Twitter</a></span></figcaption></figure><p>Greenland has <a href="https://www.bbc.com/news/world-europe-48674797">been in the news a bit lately</a>. From Huskies seemingly walking on water, to temperatures soaring to 20°C above average for the time of year, to predictions of the vast ice sheet being <a href="https://advances.sciencemag.org/content/5/6/eaav9396">lost entirely</a>, what is going on?</p>
<p>At its most simple: ice melts when it gets too warm. </p>
<p>Of course, some ice melts every time summer rolls around, but the amount of Arctic ice that melts each summer is growing, and we’re waiting to see whether this turns out to be a record-breaking year for Greenland ice melt.</p>
<p>No part of the planet is free from the impacts of human-caused climate change. But Greenland, and the Arctic more generally, is experiencing the impacts particularly severely. Temperatures in the planet’s extreme north are <a href="https://arctic.noaa.gov/Report-Card">rising twice as fast as the global average</a>. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/282182/original/file-20190702-28321-b5pbwt.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/282182/original/file-20190702-28321-b5pbwt.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/282182/original/file-20190702-28321-b5pbwt.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=199&fit=crop&dpr=1 600w, https://images.theconversation.com/files/282182/original/file-20190702-28321-b5pbwt.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=199&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/282182/original/file-20190702-28321-b5pbwt.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=199&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/282182/original/file-20190702-28321-b5pbwt.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=250&fit=crop&dpr=1 754w, https://images.theconversation.com/files/282182/original/file-20190702-28321-b5pbwt.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=250&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/282182/original/file-20190702-28321-b5pbwt.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=250&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Amplification of climate change in the Arctic.</span>
</figcaption>
</figure>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/ice-melt-in-greenland-and-antarctica-predicted-to-bring-more-frequent-extreme-weather-111082">Ice melt in Greenland and Antarctica predicted to bring more frequent extreme weather</a>
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<p>Greenland is warming so rapidly because of what climate scientists refer to as a “positive feedback”. Despite the name, these are not good. A better term might be “climate change amplifier”.</p>
<p>The Arctic has many “positive feedbacks” or “amplifiers” that worsen the effects of climate change here. For example, as snow and ice begin to melt, the surface darkens, allowing it to absorb more heat and thus melt even more. </p>
<p>This effect is most dramatic when snow and ice are lost completely, as in the case of the dramatic <a href="https://nsidc.org/arcticseaicenews/">loss of the sea ice covering the Arctic ocean</a>. Arctic sea ice loss is one of the major factors that explains why the Arctic is warming so much faster than the rest of the planet.</p>
<p>Another worrisome characteristic of climate change in the Arctic is the <a href="https://www.nature.com/articles/d41586-018-07617-1">potential for ice melt to accelerate</a>. The temperature threshold at which ice begins to melt means that once the climate has warmed enough to start melting ice, any further warming will rapidly cause an even larger amount of melting to occur. That is the reality beginning to play out in Greenland.</p>
<h2>Beginning of the 2019 summer melt season</h2>
<p>Last month, ice melt across the surface of Greenland made headlines. Surface melting spiked rapidly and was unusually strong for June. Melting was most intense around the edges of the Greenland ice sheet, and about 40% of the entire ice sheet surface was affected to some extent.</p>
<p><img width="100%" src="https://media.giphy.com/media/hrFM2stFhIqtSHAUNz/giphy.gif"></p>
<p>Greenland ice melt is typically very irregular during each summer, spiking as weather systems bring warm air masses over the ice sheet. Given this variability, it is not yet clear whether 2019 is going to be an unusually bad year for melting over Greenland – and whether it will rival the <a href="http://nsidc.org/greenland-today/2013/02/greenland-melting-2012-in-review/">worst year on record</a>, 2012, when the entire surface of the ice sheet experienced melting. </p>
<p>But what is very clear from <a href="https://nsidc.org/greenland-today/">observations since the 1970s</a> (and completely consistent with simple physics) is that as the Arctic climate warms, the Greenland summer melt season is starting earlier, lasting longer, and becoming more intense. </p>
<p>Samples of <a href="https://www.nature.com/articles/d41586-018-07617-1">older ice from inside Greenland’s ice sheet</a> paint an even clearer picture of the changes that climate warming is causing. The amount of summer melting first began to increase in the mid-1800s, <a href="https://theconversation.com/the-industrial-revolution-kick-started-global-warming-much-earlier-than-we-realised-64301">not long after human-driven climate warming began</a>. Summer melt over the past two decades has reached levels roughly 50% higher than before the Industrial Revolution, and the speed of ice loss from the Greenland sheet has increased nearly sixfold since the 1980s.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/282175/original/file-20190702-28338-1yq2hld.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/282175/original/file-20190702-28338-1yq2hld.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=205&fit=crop&dpr=1 600w, https://images.theconversation.com/files/282175/original/file-20190702-28338-1yq2hld.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=205&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/282175/original/file-20190702-28338-1yq2hld.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=205&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/282175/original/file-20190702-28338-1yq2hld.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=258&fit=crop&dpr=1 754w, https://images.theconversation.com/files/282175/original/file-20190702-28338-1yq2hld.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=258&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/282175/original/file-20190702-28338-1yq2hld.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=258&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Greenland melt intensity over the past 350 years.</span>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-industrial-revolution-kick-started-global-warming-much-earlier-than-we-realised-64301">The Industrial Revolution kick-started global warming much earlier than we realised</a>
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<hr>
<h2>Choices for the future</h2>
<p>An ice sheet has existed on Greenland for millions of years. But the geological timescales of ice sheet growth and renewal are vastly outpaced by the human-caused changes we see today.</p>
<p>A study <a href="https://advances.sciencemag.org/content/5/6/eaav9396">published in June this year</a>, at the same time surface melting of the ice sheet was spiking, predicts that if human greenhouse emissions continue unabated, by the end of this century ice loss from the Greenland ice sheet could see the ocean rise by up to 33cm. </p>
<p>If all of the Greenland ice sheet were to melt, global sea level would rise by more than 7 metres. According to the same study, that could potentially happen within 1,000 years.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/cold-and-calculating-what-the-two-different-types-of-ice-do-to-sea-levels-59996">Cold and calculating: what the two different types of ice do to sea levels</a>
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<hr>
<p>The evidence is abundantly clear: the rising temperature of the planet is causing more Arctic ice to melt during the northern summer. We cannot avoid further ice loss in coming decades, and people and ecosystems will have to adapt to this. </p>
<p>But there is still a window of opportunity to avoid the worst impacts of future climate change in the longer term. The evidence tells us that the only way to prevent the destruction of the Greenland ice sheet, and multi-metre rises in global sea level, is to make rapid, deep cuts to greenhouse gas emissions. That is a choice we still have a chance to make.</p><img src="https://counter.theconversation.com/content/119307/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Nerilie Abram receives funding from the Australian Research Council, through the Centre of Excellence for Climate Extremes and a Future Fellowship. </span></em></p>Greenland’s ice made headlines in June, as warm weather made for unseasonably widespread melting. And though this summer is still unfolding, the human fingerprint on Greenland’s ice can’t be denied.Nerilie Abram, ARC Future Fellow, Research School of Earth Sciences; Chief Investigator for the ARC Centre of Excellence for Climate Extremes, Australian National UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1174332019-06-07T12:24:39Z2019-06-07T12:24:39ZDisappearing sea ice is changing the whole ecosystem of the Arctic Ocean<figure><img src="https://images.theconversation.com/files/275683/original/file-20190521-23841-wri7sm.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">outdoorsman / shutterstock</span></span></figcaption></figure><p>I drafted this while looking north over the frozen Lincoln Sea, at the northernmost tip of Ellesmere Island in Canada. I was at Alert, a Canadian Forces Station which, at 82°N, is the most northerly permanently inhabited place on Earth. Just 815km away, across the Arctic Ocean, lay the North Pole. </p>
<p>It was May, and the sea should have still been frozen, but this year the bridge of sea ice between Ellesmere and Greenland <a href="https://nsidc.org/arcticseaicenews/">broke up early</a>, and Arctic ice began flowing down the narrow Nares Channel and south into Baffin Bay. All across the Arctic Ocean, the amount and persistence of sea ice is <a href="https://nsidc.org/arcticseaicenews/">declining</a> – September ice cover has fallen around 30% since 1980. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/275679/original/file-20190521-23835-bmw8b7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/275679/original/file-20190521-23835-bmw8b7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/275679/original/file-20190521-23835-bmw8b7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=298&fit=crop&dpr=1 600w, https://images.theconversation.com/files/275679/original/file-20190521-23835-bmw8b7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=298&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/275679/original/file-20190521-23835-bmw8b7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=298&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/275679/original/file-20190521-23835-bmw8b7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=375&fit=crop&dpr=1 754w, https://images.theconversation.com/files/275679/original/file-20190521-23835-bmw8b7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=375&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/275679/original/file-20190521-23835-bmw8b7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=375&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Alert (red dot) is at the northern end of Canada’s most northerly island.</span>
<span class="attribution"><span class="source">NASA/Goddard Space Flight Center</span></span>
</figcaption>
</figure>
<p>The Arctic is <a href="https://nsidc.org/news/newsroom/arctic-sea-ice-has-been-decline-decades-according-new-scientific-paper">warming at twice the rate</a> of the rest of the planet, and images of polar bears on small ice floes capture the imagination. But those images represent (excusing the pun) only the tip of the iceberg – the consequences of ice loss are profound and start from the very bottom of the food chain, in the microbial processes that drive the biology of the ocean.</p>
<h2>Arctic food chains sometimes start in sea ice</h2>
<p>Sea ice forms when seawater temperature falls below -1.8°C. As the ice crystals form, salt is forced out and ice brines and other dissolved constituents become trapped in a honeycomb of small channels in the ice. Cold salty water draining from the ice also sinks deep to the bottom of the oceans and <a href="https://www.nature.com/articles/nclimate3353">drives water circulation</a> across the globe.</p>
<p>As the air grows colder, the ice thickens downwards and, in the brine channels and across the ice bottom, specialised algae and bacteria grow. When sunlight returns to the Arctic in the spring and penetrates through the ice (which is rarely more than a few metres thick) these ice-algal communities start to photosynthesise, producing algal biomass and abundant <a href="https://aslopubs.onlinelibrary.wiley.com/doi/full/10.1002/lno.10260">dissolved organic matter</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/278406/original/file-20190606-98045-12jy4zx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/278406/original/file-20190606-98045-12jy4zx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/278406/original/file-20190606-98045-12jy4zx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=373&fit=crop&dpr=1 600w, https://images.theconversation.com/files/278406/original/file-20190606-98045-12jy4zx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=373&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/278406/original/file-20190606-98045-12jy4zx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=373&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/278406/original/file-20190606-98045-12jy4zx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=469&fit=crop&dpr=1 754w, https://images.theconversation.com/files/278406/original/file-20190606-98045-12jy4zx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=469&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/278406/original/file-20190606-98045-12jy4zx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=469&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Ice algae growing on the bottom of an ice core.</span>
<span class="attribution"><span class="source">Graham Underwood</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>This feeds a wide range of microscopic creatures known as zooplankton, which graze across the bottom of the ice. These zooplankton in turn feed larger animals and drive the food chain throughout spring.</p>
<p>When the ice melts more of this material flows out into the seas, providing more food resources at the bottom of food chains. In a recent study published in <a href="https://www.nature.com/articles/s41558-018-0391-7">Nature Climate Change</a>, colleagues and I showed how the different components of this organic matter derived from ice-algae are used by different species of bacteria and at different rates in underlying seawater, so that more melting ice will change the patterns of organic matter turnover in surface waters during spring. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/278411/original/file-20190606-98022-19yt6il.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/278411/original/file-20190606-98022-19yt6il.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/278411/original/file-20190606-98022-19yt6il.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/278411/original/file-20190606-98022-19yt6il.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/278411/original/file-20190606-98022-19yt6il.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/278411/original/file-20190606-98022-19yt6il.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/278411/original/file-20190606-98022-19yt6il.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/278411/original/file-20190606-98022-19yt6il.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"></a>
<figcaption>
<span class="caption">Ice-algae diatoms, right at the bottom of the Arctic food chain.</span>
<span class="attribution"><span class="source">Graham Underwood</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Different food chains may develop</h2>
<p>Not all sea ice melts each summer – or at least it didn’t. <a href="https://nsidc.org/cryosphere/seaice/characteristics/multiyear.html">Multi-year ice</a> can go through a number of years of melting and growing, getting thicker and more structurally complex. But, over time, this multi-year ice has become rarer. In the 1980s, around one-third of the Arctic’s ice cover was more than four years old – today, such ice is almost nonexistent. Instead, more <a href="https://nsidc.org/cryosphere/glossary/term/first-year-ice">first-year ice</a> will form and completely melt each year, providing new food inputs into areas of ocean that were previously permanently covered in ice.</p>
<p>This has significant consequences. Less ice cover in summer means more open ocean water, which – as it is darker – absorbs more sunlight and heat, making it harder to freeze in the autumn. Open water also means the wind can stir up the sea and slow the process of <a href="https://science.sciencemag.org/content/356/6335/285.abstract">refreezing</a>. More open water in summer will change the plankton communities, and then the animals that feed on them. </p>
<p>Some species are moving north. Already the Barents Sea between Norway and Svalbard is now rarely covered in ice in winter – and North Atlantic species such as <a href="https://www.nature.com/articles/s41598-019-42097-x.pdf">cod</a> and top predators such as orca are moving in. Specialist species that rely on ice such as polar bears, ringed seals, walrus and <a href="https://www.wur.nl/en/newsarticle/Strong-link-between-polar-cod-and-sea-ice-of-the-Arctic-Ocean.htm">Arctic cod</a> are losing their habitats, while non-indigenous species are expanding their <a href="https://onlinelibrary.wiley.com/doi/pdf/10.1111/gcb.14469">range</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/278403/original/file-20190606-97994-nnzd0i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/278403/original/file-20190606-97994-nnzd0i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/278403/original/file-20190606-97994-nnzd0i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=395&fit=crop&dpr=1 600w, https://images.theconversation.com/files/278403/original/file-20190606-97994-nnzd0i.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=395&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/278403/original/file-20190606-97994-nnzd0i.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=395&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/278403/original/file-20190606-97994-nnzd0i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=496&fit=crop&dpr=1 754w, https://images.theconversation.com/files/278403/original/file-20190606-97994-nnzd0i.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=496&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/278403/original/file-20190606-97994-nnzd0i.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=496&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 author, at 82ºN.</span>
<span class="attribution"><span class="source">Graham Underwood</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>For some, a warmer Arctic brings opportunities. Reduced ice cover means ships can use the north-east and north-west passages, significantly shortening journey times between the Atlantic and the Pacific. New fisheries may develop, and less ice means access to oil and gas resources becomes <a href="https://link.springer.com/article/10.1007/s13280-017-0959-x">possible</a>.</p>
<p>But these benefits to some, come at potentially huge costs. In addition to the changes in the ocean, a warmer Arctic could disrupt ocean circulation and global weather systems, while permafrost will continue to thaw, potentially releasing greenhouse gases currently locked up in frozen soils. </p>
<p>A whole ecosystem, rich in specialist species – many barely studied – is changing before our eyes. The Arctic is a beautiful and harsh place, posing serious logistical challenges for scientific investigation. But even there, on the top of the world, far from centres of human population, our impact is evident.</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">
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<span class="caption"></span>
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</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=Imagineheader1117433">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/117433/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Graham Underwood's work on sea ice microbiology has been funded by the UK Natural Environment Research Council, and recent field work in Alert Canada in 2019 with Dr Christine Michel was supported by the Canadian Department of Fisheries and Oceans, Multidisciplinary Arctic Programme Last Ice program. </span></em></p>Algae at the bottom of the Arctic food chain relies on sea ice.Graham J. C. Underwood, Professor of Marine and Freshwater Biology, University of EssexLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1075902018-11-26T13:17:11Z2018-11-26T13:17:11ZThe Arctic is turning brown because of weird weather – and it could accelerate climate change<figure><img src="https://images.theconversation.com/files/247232/original/file-20181126-140537-1i6tn11.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">'Brow-raising browning.</span> <span class="attribution"><span class="source">Rachael Treharne</span>, <span class="license">Author provided</span></span></figcaption></figure><p>Over the last few years Arctic scientists have reported a surprising finding: large areas of the Arctic are turning brown. This is in part due to extreme events linked to winter weather, such as sudden, short-lived periods of extreme warmth. These events are occurring as the climate warms, which is happening <a href="https://www.amap.no/documents/doc/Snow-Water-Ice-and-Permafrost.-Summary-for-Policy-makers/1532">twice as fast</a> in the Arctic compared with the rest of the planet. Extreme events are therefore happening more and more often, with increasingly severe effects – including widespread damage and death in Arctic plants.</p>
<p>This “browning” of plant communities has happened over thousands of square kilometres or more. However, until recently we knew very little about what this might mean for the balance between carbon uptake and release in Arctic ecosystems. Given that the <a href="https://www.nature.com/articles/nature08031">Arctic stores twice as much carbon</a> as the atmosphere, this is a pressing concern.</p>
<p>Now, <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/gcb.14500">our study</a> has shown that extreme climatic events can significantly reduce the ability of Arctic ecosystems to take up carbon –- with implications for whether the Arctic will help combat climate change, or accelerate it.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/247235/original/file-20181126-140531-ps6709.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/247235/original/file-20181126-140531-ps6709.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/247235/original/file-20181126-140531-ps6709.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/247235/original/file-20181126-140531-ps6709.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/247235/original/file-20181126-140531-ps6709.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/247235/original/file-20181126-140531-ps6709.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/247235/original/file-20181126-140531-ps6709.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">Dead and brown vegetation on a heathland in Norway.</span>
<span class="attribution"><span class="source">Rachael Treharne</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>The carbon cost of extreme weather</h2>
<p>To understand how extreme events are affecting Arctic heathlands, we travelled to the Lofoten Islands in northern Norway where coastal, sub-Arctic plant communities act as a bellwether for future climate change in the far north by exhibiting the effects of warming in the region first.</p>
<p>Here we found the effects of two extreme winter weather events. First, “frost drought” had caused extensive plant dieback. Frost drought occurs when the insulating layer of snow which usually protects plants from the harsh Arctic winter is melted, typically by unusually high winter temperatures. If plants remain exposed to cold, windy conditions for long enough, they continually lose water and are unable to replace it from the frozen soil. Eventually, they succumb to drought.</p>
<p>The second event was “extreme winter warming” – a sudden burst of high temperatures during winter which melts the snow and tricks evergreen plants into preparing for spring by shedding their cold tolerance. When the warm period is over, the return of cold temperatures usually kills the plant. In this case, however, we found something unexpected. Heathland plants had survived this extreme winter warming event, but were showing evidence of severe stress, visible as a deep, persistent dark red colour in shoots and leaves.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/247227/original/file-20181126-140522-19j2ysc.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/247227/original/file-20181126-140522-19j2ysc.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/247227/original/file-20181126-140522-19j2ysc.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/247227/original/file-20181126-140522-19j2ysc.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/247227/original/file-20181126-140522-19j2ysc.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/247227/original/file-20181126-140522-19j2ysc.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/247227/original/file-20181126-140522-19j2ysc.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1005&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Deep red pigmentation indicates that this plant is under stress from the unpredictable climate.</span>
<span class="attribution"><span class="source">Rachael Treharne</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>We measured how much carbon dioxide was being taken in and released by the plants in three vegetation types: damaged heathland (where the dominant evergreen species had been killed by frost drought), stressed heathland, and healthy, green heathland which had escaped the effects of either extreme event. This was done in three measurement periods across the growing season.</p>
<p>We found that these extreme winter conditions reduced how much carbon was absorbed in heathland ecosystems <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/gcb.14500">by up to 50%</a> across the entire growing season. This is a huge reduction in the ability of a widespread Arctic ecosystem to remove carbon from the atmosphere. </p>
<p>Surprisingly, this was the case both in damaged heathland, where a large part of the vegetation had been killed, and in stressed heathland. Although the processes driving this change were different in each type of heathland, this clearly shows that we need to consider the role of plant stress in limiting plant carbon uptake to fully appreciate the consequences of extreme climatic events.</p>
<h2>The Great Brown North</h2>
<p>What does this mean for the Arctic? We now know that extreme climatic events could significantly reduce the ability of Arctic ecosystems to take up carbon and combat climate change.</p>
<p>This is especially concerning as the impacts of browning are in stark contrast to those of a better understood response of Arctic ecosystems to climate change: “<a href="https://pubs.rsc.org/en/content/articlelanding/2009/em/b911677j/unauth#!divAbstract">Arctic greening</a>”, or the tendency for plants to become taller and more productive as Arctic summers warm.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/247237/original/file-20181126-140522-vkjk57.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/247237/original/file-20181126-140522-vkjk57.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/247237/original/file-20181126-140522-vkjk57.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/247237/original/file-20181126-140522-vkjk57.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/247237/original/file-20181126-140522-vkjk57.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/247237/original/file-20181126-140522-vkjk57.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/247237/original/file-20181126-140522-vkjk57.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">Instruments measuring carbon uptake and release at the test site.</span>
<span class="attribution"><span class="source">Rachael Treharne</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Many climate models currently assume <a href="https://www.nature.com/articles/nclimate2697">arbitrary levels of greening</a> across the Arctic, and therefore that Arctic ecosystems will take up more carbon in the future – slowing climate change. The scale of the browning we’ve seen in recent years combined with the negative impacts on carbon uptake reported here suggests that the reality may be more complex, calling into question our understanding of the role of the Arctic in the Earth’s climate.</p>
<p>What does this mean for us? The impact of extreme weather events in the Arctic has global consequences. It is clear that our current efforts to tackle climate change are dangerously inadequate, but ambitious action now could cut how much the Arctic is expected to <a href="https://www.amap.no/documents/doc/Snow-Water-Ice-and-Permafrost.-Summary-for-Policy-makers/1532">warm by as much as 7°C</a>. This is critical to minimising the impacts of climate change both in Arctic ecosystems and worldwide.</p><img src="https://counter.theconversation.com/content/107590/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Rachael Treharne receives funding from Adapting to the Challenges of a Changing Environment (ACCE) doctoral training partnership, funded by the Natural Environment Research Council.</span></em></p>Extreme climatic events are harming plant communities in the Arctic. The resulting colour change is bad news for the region’s carbon storage.Rachael Treharne, PhD Researcher in Arctic Ecology, University of SheffieldLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1050322018-10-22T10:37:35Z2018-10-22T10:37:35ZIn Alaska, everyone’s grappling with climate change<figure><img src="https://images.theconversation.com/files/241493/original/file-20181019-105754-1mij805.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">2016's warm winter meant not enough snow for the start of the Iditarod sled dog race in Anchorage, so it was brought by train from 360 miles north.</span> <span class="attribution"><a class="source" href="http://www.apimages.com/metadata/Index/Iditarod-Snow-Train/647a26a12fba4787b94c80059f176526/1/0">AP/Rachel D'Oro</a></span></figcaption></figure><p>Coastal villages are washing into the Bering Sea, trees are sprouting in the tundra and shipping lanes are opening in an ocean that was once locked in ice. In Alaska, <a href="https://www.globalchange.gov/explore/alaska">climate change isn’t a distant or abstract concern</a>.</p>
<p>As a climate change researcher at the <a href="https://uaf-iarc.org/">International Arctic Research Center</a> at the <a href="https://www.uaf.edu/uaf/">University of Alaska, Fairbanks</a>, I see a lot of compelling data – and also hear a lot of compelling stories. Both data and stories are important. </p>
<p>For everyone from the National Park Service to the military, from the oil industry to city managers to traditional hunters, adapting to climate change is the new reality in Alaska.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/241496/original/file-20181019-105776-ih2nqc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/241496/original/file-20181019-105776-ih2nqc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/241496/original/file-20181019-105776-ih2nqc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=286&fit=crop&dpr=1 600w, https://images.theconversation.com/files/241496/original/file-20181019-105776-ih2nqc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=286&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/241496/original/file-20181019-105776-ih2nqc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=286&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/241496/original/file-20181019-105776-ih2nqc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=359&fit=crop&dpr=1 754w, https://images.theconversation.com/files/241496/original/file-20181019-105776-ih2nqc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=359&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/241496/original/file-20181019-105776-ih2nqc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=359&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 Aggie Creek Fire near Fairbanks in 2015.</span>
<span class="attribution"><a class="source" href="https://www.noaa.gov/media-release/scientists-strong-evidence-human-caused-climate-change-intensified-2015-heat-waves">NOAA/Philip Spor</a></span>
</figcaption>
</figure>
<h2>It’s happening – and fast</h2>
<p>Almost 12 years ago, we embarked upon a new research effort at our state university. The idea was simple: Meet the needs of those planning for our state’s future by providing information on climate change that was local, relevant and scientifically valid. </p>
<p>First named the <a href="https://www.snap.uaf.edu/">Scenarios Network for Alaska Planning (SNAP)</a>, we soon had to add the word “Arctic” to our name, because we realized that Canada and other countries from the polar region were as eager for long-term forecasts of climate change trends as Alaska was. </p>
<p>In the Arctic and sub-Arctic, climate change is accelerated and its effects are profound. This is primarily the result of what is known as the “albedo effect”: As we lose reflective ice and snow due to warming, more heat-absorbing dark ground and water are exposed. Thus, <a href="https://www.climate.gov/teaching/resources/earths-albedo-and-global-warming">local warming gets even more extreme</a>.</p>
<p>Just where climate change effects are extreme, data is often limited. Few weather stations offer long-term reliable histories. Populations are sparse. So we glean information from a variety of sources and <a href="https://www.snap.uaf.edu/methods/overview">combine that with</a> historical data and the accumulated knowledge of people who live on the landscape. All point <a href="https://www.commerce.alaska.gov/web/dcra/climatechange.aspx">incontrovertibly to a warming environment</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/241465/original/file-20181019-105776-17op69u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/241465/original/file-20181019-105776-17op69u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/241465/original/file-20181019-105776-17op69u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=415&fit=crop&dpr=1 600w, https://images.theconversation.com/files/241465/original/file-20181019-105776-17op69u.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=415&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/241465/original/file-20181019-105776-17op69u.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=415&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/241465/original/file-20181019-105776-17op69u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=522&fit=crop&dpr=1 754w, https://images.theconversation.com/files/241465/original/file-20181019-105776-17op69u.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=522&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/241465/original/file-20181019-105776-17op69u.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=522&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 ‘drunken forest,’ where trees lean and tilt when the permafrost under them thaws.</span>
<span class="attribution"><a class="source" href="https://www.nps.gov/wrst/learn/nature/permafrost.htm">National Park Service</a></span>
</figcaption>
</figure>
<h2>Widespread effects</h2>
<p>The ways in which this change plays out are as diverse as the people and landscapes of Alaska. </p>
<p>Our state includes not only Arctic tundra underlain by the permanently frozen ground called “permafrost,” but also vast stretches of spruce, birch, aspen, alder and willow trees: the boreal forest. To the west, the windy Aleutian islands stretch out into the Pacific, and to the southeast, Alaska hugs the coast of British Colombia and boasts dense and towering coastal rainforest.</p>
<p>Across the state, hundreds of small communities – primarily Alaska Native villages – are not connected to the road system. Accessible only by air, sea, river or winter trails, these communities maintain traditional <a href="https://www.nativefederation.org/subsistence/">subsistence lifestyles</a> based on <a href="http://www.adfg.alaska.gov/index.cfm?adfg=subsistence.main">hunting, fishing and gathering food and other resources</a>. </p>
<p>Meanwhile, the state’s coffers are enriched by money from oil and gas extraction – which are both primary sources of climate change, an <a href="https://www.nytimes.com/2018/05/15/climate/alaska-climate-change.html">irony that has not gone unnoticed</a> by those struggling to craft long-term plans for Alaska.</p>
<p>With 6,640 miles of coastline, Alaska is an ocean-dependent state. Due to loss of <a href="http://seaiceatlas.snap.uaf.edu/">sea ice</a> that protects soft soils from seasonal storms, huge stretches of this coastline are washing into the Bering Sea. For communities at risk of erosion, all other concerns pale in comparison. At stake are not only structures and money, but also traditions, a sense of place, and even lives. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/241491/original/file-20181019-105776-gvu8dh.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/241491/original/file-20181019-105776-gvu8dh.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/241491/original/file-20181019-105776-gvu8dh.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=363&fit=crop&dpr=1 600w, https://images.theconversation.com/files/241491/original/file-20181019-105776-gvu8dh.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=363&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/241491/original/file-20181019-105776-gvu8dh.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=363&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/241491/original/file-20181019-105776-gvu8dh.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=456&fit=crop&dpr=1 754w, https://images.theconversation.com/files/241491/original/file-20181019-105776-gvu8dh.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=456&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/241491/original/file-20181019-105776-gvu8dh.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=456&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Thawing permafrost caused this buckling on the Alaska Highway.</span>
<span class="attribution"><a class="source" href="https://www.fhwa.dot.gov/publications/publicroads/10mar/05.cfm">USDA/NRCS/Joe Moore</a></span>
</figcaption>
</figure>
<p>In <a href="https://www.cnn.com/2017/03/29/us/sutter-shishmaref-esau-tragedy/index.html">Shishmaref</a>, an Inupiat village with about 500 residents, homes have slipped off cliff edges and a hunter fell through thin ice. <a href="https://www.nytimes.com/interactive/2016/11/29/science/alaska-global-warming.html">Relocation</a> is costly and <a href="https://www.scientificamerican.com/article/alaskas-coast-is-vanishing-1-storm-at-a-time/">a last-ditch option</a>. </p>
<p>On the coast of the Arctic Ocean, <a href="https://www.mmc.gov/priority-topics/arctic/climate-change/">walruses, seals and polar bears</a> are no longer finding the ice they need to rest, hunt, mate and breed. The <a href="https://www.theguardian.com/environment/2016/dec/19/alaska-sea-ice-vanishing-climate-change-indigenous-people">shortening sea ice seasons</a> are also threatening <a href="https://www.pri.org/stories/2018-02-22/subsistence-hunters-adapt-warming-alaska-new-tools">traditional hunting practices</a>. </p>
<p>Even for inland residents, the health of the ocean is crucial, because the <a href="https://www.sciencemag.org/news/2014/07/worsening-ocean-acidification-threatens-alaska-fisheries">salmon caught in Alaska’s rivers</a> fatten in the open ocean. Should climate change render the <a href="https://www.aoos.org/alaska-ocean-acidification-network/">ocean too acidic</a> due to changing atmospheric carbon, the tiny sea snails on which the salmon feed would be at risk because they may no longer be able to form their shells.</p>
<p><iframe id="wcrbO" class="tc-infographic-datawrapper" src="https://datawrapper.dwcdn.net/wcrbO/4/" height="400px" width="100%" style="border: none" frameborder="0"></iframe></p>
<p>In the interior of the state, <a href="https://www.washingtonpost.com/news/energy-environment/wp/2015/07/26/alaskas-terrifying-wildfire-season-and-what-it-says-about-climate-change/?noredirect=on&utm_term=.00d1e7922d53">forest fires are burning bigger and hotter</a> than in the past. The <a href="https://globalforestatlas.yale.edu/boreal-forest/boreal-ecoregions-ecology/fire-boreal">boreal forest system</a> is dependent on the renewal of young vegetation after a burn. But with hotter, drier spring weather, <a href="https://akfireinfo.com/about/">sparks from dry lightning have torched</a> <a href="https://news.nationalgeographic.com/2017/06/lightning-wildfires-boreal-forest-climate-change-global-warming/">millions more acres than usual</a>. Neighborhoods have been evacuated, and dense palls of smoke <a href="https://www.usatoday.com/story/news/2015/06/15/sockeye-wildfire-burns-alaska/71264046/">have spread across the state</a>. </p>
<p>Such fires also accelerate the other major inland change: <a href="https://www.nytimes.com/interactive/2017/08/23/climate/alaska-permafrost-thawing.html">permafrost thaw</a>. On the newly soft, water-saturated ground, roads buckle and foundations fail as <a href="http://discovermagazine.com/2018/jun/something-stirs">once-frozen soils slump and shift</a>. <a href="http://onlinepubs.trb.org/onlinepubs/trnews/trnews284alaska.pdf">Roads, runways and bridges can sustain costly damage</a>. Here in Fairbanks, <a href="https://www.bbc.com/news/science-environment-34540414">tilted and sinking homes</a> are a common sight. </p>
<p>As organic soils thaw, they start to decay, which in turn releases carbon into the atmosphere. These carbon releases, which exacerbate climate change, <a href="https://www.newsweek.com/arctic-permafrost-lakes-bubbling-methane-nasa-1119624">are particularly potent in the form</a> of <a href="https://www.adn.com/arctic/2018/09/24/across-the-arctic-lakes-are-leaking-dangerous-greenhouse-gases/">methane bubbling from lakes</a>.</p>
<h2>Urban problems too</h2>
<p>About half the population of Alaska lives in Anchorage. Here, livelihoods tend to be more urban, but <a href="http://climate.gi.alaska.edu/YearlyWeather">recreation often depends on snow</a> – <a href="https://www.newyorker.com/culture/culture-desk/the-end-of-winter">snow that is not showing up</a>. </p>
<p>The <a href="https://www.climate.gov/news-features/features/low-snow-drives-iditarod-north-third-time">Iditarod sled dog race</a> has had to move its starting line and reroute mushers. Tourism businesses are suffering. The city, like many communities around the state, is working on a <a href="http://climatechange.gov.alaska.gov/wp-content/uploads/sites/11/2018/08/Climate-Action-Plan-v4_072718.pdf">climate change adaptation plan</a>. </p>
<p>Meanwhile, around the state capital of Juneau and other Southeast Alaska communities, the mountains are losing their snow caps early and gaining them late. Water is flowing downstream out of season, which may impact everything from <a href="https://thefishsite.com/articles/alaska-fish-factor-new-study-investigates-climate-changes-impact-on-alaskan-salmon">salmon stocks</a> to hydroelectric <a href="http://www.juneau.org/sustain/climate-action-plan/">power generation</a>. Iconic yellow cedar trees are dying due to lack of <a href="https://www.fs.fed.us/pnw/research/climate-change/yellow-cedar/">protective snow cover on their roots</a>. </p>
<p>Here, as elsewhere in the north, <a href="https://www.nationalgeographic.com/environment/2018/09/plastics-birds-climate-change-alaska-news/">whole ecosystems are changing</a>, putting some migratory birds such as eiders and some small Arctic mammals such as pikas and marmots <a href="https://www.adn.com/wildlife/article/changing-climate-will-transform-wildlife-habitat-northwestern-alaska-study-says/2015/03/28/">at risk</a>. Also threatened are lifestyles and livelihoods linked to Alaska’s caribou herds, which may be <a href="http://www.adfg.alaska.gov/index.cfm?adfg=wildlifenews.view_article&articles_id=356">losing the lichen they need to survive</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/241495/original/file-20181019-105761-89dksk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/241495/original/file-20181019-105761-89dksk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/241495/original/file-20181019-105761-89dksk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=311&fit=crop&dpr=1 600w, https://images.theconversation.com/files/241495/original/file-20181019-105761-89dksk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=311&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/241495/original/file-20181019-105761-89dksk.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=311&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/241495/original/file-20181019-105761-89dksk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=390&fit=crop&dpr=1 754w, https://images.theconversation.com/files/241495/original/file-20181019-105761-89dksk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=390&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/241495/original/file-20181019-105761-89dksk.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=390&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 airstrip in Kivalina, an Alaska Native village, is in danger of being wiped out by erosion.</span>
<span class="attribution"><a class="source" href="https://toolkit.climate.gov/case-studies/relocating-kivalina">US Climate Resilience Toolkit/ Millie Hawley,</a></span>
</figcaption>
</figure>
<h2>Mitigation, adaptation and change</h2>
<p>Although mitigation of climate change via reductions in global greenhouse gas emissions is crucial, even the most optimistic scenarios include substantial shifts in temperature for many decades into the future. While adapting to this change is likely to be costly, failing to adapt will be costlier still.</p>
<p>Recognizing this, Alaska’s communities and land managers are taking action. </p>
<p>For the past year, <a href="https://www.juneauempire.com/news/gov-accepts-climate-change-plan/">a statewide plan</a> has been in development. The University of Alaska and <a href="http://www.muni.org/Departments/Mayor/AWARE/resilientanchorage/pages/climateactionplan.aspx">the municipality of Anchorage</a> are creating a Climate Action Plan to address issues as diverse as invasive beetles, cultural loss and lack of skiing opportunities. For the village of <a href="http://www.alaskajournal.com/2018-05-23/federal-fund-injection-boosts-effort-relocate-newtok#.W8mRpPlReM8">Newtok</a>, planning meant seeking federal funding for total relocation.</p>
<p>When <a href="https://www.adn.com/alaska-news/environment/2017/08/04/retreating-exit-glacier-has-become-an-icon-of-climate-change/">a glacier at the heart of a National Park is rapidly melting</a>, the thaw itself becomes part of the educational mission of the park. Federal agencies, including <a href="https://www.nps.gov/articles/aps-v12-i2-c1.htm">the National Park Service</a>, the Department of Defense, <a href="https://landscape.blm.gov/geoportal/catalog/REAs/REAs.page">the Bureau of Land Management</a> and <a href="https://www.fs.usda.gov/detail/chugach/home/?cid=stelprdb5281977">the Forest Service</a> are working with <a href="https://www.snap.uaf.edu/">my planning group</a> and other partners to incorporate climate change into their visions of the future. </p>
<p>For those who live and work in Alaska, adapting to such profound changes in our state is hard. Failing to do so would likely be catastrophic.</p><img src="https://counter.theconversation.com/content/105032/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Nancy Fresco receives climate change research funding via grants from diverse governmental and non-governmental sources, including but not limited to the US Department of Agriculture, the US National Park Service, the Government of the Northwest Territories, the US Bureau of Land Management, the Alaska Department of Transportation, and the US Department of Defense.</span></em></p>For everyone from traditional hunters to the military, the National Park Service to the oil industry, climate change is the new reality in Alaska. Government, residents and businesses are all trying to adapt.Nancy Fresco, SNAP Coordinator, Research Faculty, University of Alaska FairbanksLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1023122018-09-04T22:51:16Z2018-09-04T22:51:16ZAs ice recedes, the Arctic isn’t prepared for more shipping traffic<figure><img src="https://images.theconversation.com/files/234337/original/file-20180830-195331-rhsave.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The Canadian Coast Guard icebreaker Louis S. St-Laurent sails past a iceberg in Lancaster Sound in 2008.
</span> <span class="attribution"><span class="source">THE CANADIAN PRESS/Jonathan Hayward</span></span></figcaption></figure><p>I was aboard the 364-foot Russian research-cruise ship <em>Akademik Ioffe</em> when it came to a violent stop after <a href="https://www.cbc.ca/news/canada/north/kugaaruk-passenger-ship-refloated-arctic-1.4799050">grounding on a shoal in a remote region of the Gulf of Boothia</a> in Canada’s Arctic. Fortunately, none of the 102 passengers and 24 crew members were injured. Chemical contaminants that may or may not have been pumped out with the bilge water seemed to be minor. </p>
<p>It could have ended up a lot worse. I was on the ship representing <a href="https://e360.yale.edu/">Yale Environment 360</a>, which commissioned me to report on climate change in the Arctic and the research that scientists and students with the <a href="https://northwestpassageproject.org/">U.S. National Foundation sponsored Northwest Passage Project</a> were to be conducting on that three-week voyage.</p>
<p>It took nearly nine hours for a Hercules aircraft to fly in from the Canadian National Defence Joint Rescue Centre in Trenton, Ont., 12 hours for another DND plane to come in from Winnipeg and 20 hours for a Canadian Coast Guard helicopter to fly over. By then we were boarding the <em>Akademik Vavilov</em>, a Russian sister ship that had come to the rescue. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/234338/original/file-20180830-195304-1o04hzd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/234338/original/file-20180830-195304-1o04hzd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=398&fit=crop&dpr=1 600w, https://images.theconversation.com/files/234338/original/file-20180830-195304-1o04hzd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=398&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/234338/original/file-20180830-195304-1o04hzd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=398&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/234338/original/file-20180830-195304-1o04hzd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=500&fit=crop&dpr=1 754w, https://images.theconversation.com/files/234338/original/file-20180830-195304-1o04hzd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=500&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/234338/original/file-20180830-195304-1o04hzd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=500&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Passengers aboard the Russian research/cruise ship Akademik Ioffe watch a Canadian military aircraft fly overhead as they wait to be rescued after running aground on a shoal in the Arctic.</span>
<span class="attribution"><span class="source">Edward Struzik</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Dangerous scenarios</h2>
<p>Had the weather not worked in our favour and had there been thick ice such as the kind we had sailed through hours earlier, we would have faced a number of challenging and potentially dangerous scenarios.</p>
<p>Powerful winds could have spun us around on that rock, possibly ripping a hole into the hull that might have been bigger than the one that was presumably taking in the water we saw being pumped out of the ship. Thick ice grinding up against the ship would have made it almost impossible to get everyone off into lifeboats. </p>
<p>I had warned about a scenario like this in my book <em><a href="https://www.ubcpress.ca/future-arctic">Future Arctic, Field Notes from A World On The Edge</a></em>. Only 10 per cent of the Arctic Ocean in Canada, and less than two per cent of the Arctic Ocean in the United States, is charted. Only 25 per cent of the Canadian paper charts are deemed to be good. Some of the U.S. charts go back to the days of Captains Cook and Vancouver and the time when the Russians owned Alaska.</p>
<p>I’m not the only one who has been raising the red flag. Arctic experts such as <a href="https://arctic.ucalgary.ca/research-associate/rob-huebert">Rob Huebert</a>, <a href="http://lackenbauer.ca/">Whitney Lackenbauer</a>, <a href="http://byers.typepad.com/arctic/2008/11/poli-369a-3-arctic-sovereignty-and-international-relations.html#more">Michael Byers</a> and the federal Commissioner of the Environment and Sustainable Development have all highlighted the rising risks of shipping in the Arctic, and the formidable challenges associated with timely search and rescues and the staging of oil spill cleanups.</p>
<h2>Groundings have increased</h2>
<p>Since the <a href="https://www.theatlantic.com/photo/2014/03/the-exxon-valdez-oil-spill-25-years-ago-today/100703/">catastrophic grounding of the <em>Exxon Valdez</em></a> off the coast of Alaska in 1989, the list of groundings of fuel tankers, drilling ships, cargo ships and passenger vessels plying the waters of the North American Arctic has risen significantly.</p>
<p>Most notable among them were the cruise ship <em>Hanseatic</em>, which <a href="https://www.theglobeandmail.com/opinion/canadas-not-ready-to-have-the-world-in-the-arctic/article4481519/">ran aground in the Canadian Arctic in 1996</a>, the <em>Clipper Adventurer</em> which <a href="https://www.cbc.ca/news/canada/north/cruise-ship-clipper-adventurer-nunavut-judgement-1.3973937">ran aground in Coronation Gulf in 2010</a> and the <em>Nanny</em>, a fuel tanker that <a href="https://www.cbc.ca/news/canada/north/mv-nanny-aground-chesterfield-inlet-tsb-report-1.3490781">ran aground near Baker Lake in 2012 </a>in an area where marine investigators say there is little margin for error. It was the fifth grounding in that area since 2007.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/234339/original/file-20180830-195325-1h17ve9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/234339/original/file-20180830-195325-1h17ve9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/234339/original/file-20180830-195325-1h17ve9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/234339/original/file-20180830-195325-1h17ve9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/234339/original/file-20180830-195325-1h17ve9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/234339/original/file-20180830-195325-1h17ve9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/234339/original/file-20180830-195325-1h17ve9.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">Passengers disembark the Akademik Ioffe after the Russian ship ran aground in the Canadian Arctic.</span>
<span class="attribution"><span class="source">Edward Struzik</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>As sea ice continues to recede in the Arctic, it provides cruise, cargo and tanker companies with new opportunities, and emboldens small vessels to venture into uncharted areas. A recent analysis suggests that <a href="https://psmag.com/environment/retreating-arctic-ice-has-shifted-shipping-routes-180-miles-closer-to-the-north-pole">the average Arctic ship route has moved more than 180 miles closer to the North Pole in the past seven years</a>. Mines such as the one at Mary River on Baffin Island are planning to use ships to transport their ore. Bigger cruise ships such as the <em>Crystal Serenity</em> that sailed through the Northwest Passage with 1,000 passengers and 600 crew members in 2017<a href="http://www.crystalcruises.com/northwest-passage-cruise"> are beginning to test these opportunities</a>.</p>
<h2>No rescue ports</h2>
<p>There are other factors portending future disasters. There are no ports in the North American Arctic from which to stage a rescue or an oil spill cleanup.</p>
<p>Icebreakers are few and far between. The U.S. Coast Guard has just one in operation. Canada has a few more, but many of them are well on their way to being decommissioned. </p>
<p>Weather forecasting capabilities are poor due to the shortage of meteorological stations and the increasingly unpredictable nature of Arctic weather. Powerful summers storms such as the <a href="https://earthobservatory.nasa.gov/images/78812/2012-arctic-cyclone">record-breaking summer cyclone that tore through the Arctic in 2012 </a>are on the increase. Stable shorefast ice is letting go in unpredictable ways.</p>
<p>Our ship, for example, was forced to make a last-minute change to the starting route because of ice that was blocking passage into Resolute Bay. Recognizing the challenges, two cruise companies reportedly cancelled their expeditions this year on short notice. </p>
<p>There is a lot that can and needs to be done to reduce future risks. The Canadian government could compel ships to use forward looking multi-beam sonar with Bluetooth technology. Charts can and need to be updated rapidly. More weather stations are needed. The dumping of bilge water should be banned. A search and rescue team should be seasonally based in a strategic part of the Arctic. An Arctic port is needed sooner rather than later.</p>
<p>There is also a need to determine what impact future shipping will have on beluga and narwhal migrations. </p>
<p>There is time to play catch-up because there are few signs that shipping companies are in a hurry to exploit the short cuts that the Northwest Passage offers between the Atlantic and the Pacific. But the number of partial transits will increase as cruise ships, mining companies and future oil and gas activity focus their eyes on the Arctic.</p>
<p>As things stand now, we are not prepared.</p><img src="https://counter.theconversation.com/content/102312/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Edward Struzik 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>New shipping opportunities are opening up in the Arctic as sea ice continues to recede. But travel is still dangerous and the region isn’t equipped to deal with more vessel traffic.Edward Struzik, Fellow, Queen's Institute for Energy and Environmental Policy, School of Policy Studies, Queen's University, OntarioLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1006282018-08-30T10:05:19Z2018-08-30T10:05:19ZExtreme weather in Europe linked to less sea ice and warming in the Barents Sea<figure><img src="https://images.theconversation.com/files/233304/original/file-20180823-149481-edw6o8.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/ice-barents-sea-arctic-ocean-1049664986?src=m2dlM9kfoPiV9xMdP1Onww-1-86">Vladimir Lugai/Shutterstock</a></span></figcaption></figure><p>The cold, remote Arctic Ocean and its surrounding marginal seas have experienced climate change at a rate not seen at lower latitudes. Warming air, land and sea temperatures, and large declines in seasonal Arctic sea ice cover are all symptoms of the changing Arctic climate. Although these changes are occurring in relatively remote locations, there is <a href="https://theconversation.com/a-melting-arctic-and-weird-weather-the-plot-thickens-37314">growing evidence to link</a> Arctic sea ice retreat to <a href="https://theconversation.com/is-warming-in-the-arctic-behind-this-years-crazy-winter-weather-89740">increasingly erratic weather patterns</a> over <a href="https://theconversation.com/beast-from-the-east-and-freakishly-warm-arctic-temperatures-are-no-coincidence-92774">the northern hemisphere</a>.</p>
<p>As sea ice declines, areas of open water increase, allowing the ocean to lose more heat to the atmosphere. Heat lost from the ocean to the atmosphere reduces the atmospheric pressure which provides more energy to storms and increases their cloud content through evaporation. </p>
<p>Water flowing north from the Atlantic Ocean provides a major source of heat to the Arctic Ocean and surrounding continental shelf seas. While the Atlantic Water (the particular water mass in the Arctic ocean) carries enough heat to melt all the floating Arctic sea ice in less than five years, it is currently insulated from the surface by a lighter, fresher layer of water over most of the central Arctic Ocean. </p>
<p>However, this paradigm appears to be changing. North of Svalbard, Atlantic Water heat has been mixed up towards the surface, resulting in increased surface heat lost to the atmosphere over the ever greater area of open ocean. This change has recently been <a href="https://theconversation.com/heat-from-the-atlantic-ocean-is-melting-arctic-sea-ice-further-eastwards-than-ever-before-76108">shown to enhance the rate</a> of sea ice loss eastwards. </p>
<h2>Barents Sea changes</h2>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/233302/original/file-20180823-149490-17wt79g.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/233302/original/file-20180823-149490-17wt79g.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/233302/original/file-20180823-149490-17wt79g.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=548&fit=crop&dpr=1 600w, https://images.theconversation.com/files/233302/original/file-20180823-149490-17wt79g.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=548&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/233302/original/file-20180823-149490-17wt79g.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=548&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/233302/original/file-20180823-149490-17wt79g.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=689&fit=crop&dpr=1 754w, https://images.theconversation.com/files/233302/original/file-20180823-149490-17wt79g.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=689&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/233302/original/file-20180823-149490-17wt79g.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=689&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Location of the Barents Sea.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Barents_Sea_map.png">Wikimedia</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>A key Arctic region for Atlantic Water heat exchange with the atmosphere is the Barents Sea. Atlantic Water flowing east through the Barents Sea Opening – between Bear Island, and northern Norway – remains exposed to the atmosphere as it circulates through the central Barents Sea. It gradually cools and becomes fresher (due to sea ice melting) as it moves eastwards to the Kara Sea. </p>
<p>In the Barents Sea, sea ice forms every autumn and melts in late spring/summer. In the northern part of the sea, a north-south change from cold to warm sea surface temperatures signals the presence of the Polar Front, which separates cold Arctic water from the warm Atlantic water. The meeting of the two water masses, its location and the temperature difference across it reflects changes in Barents Sea circulation.</p>
<p>During years with low seasonal sea ice concentrations (when there’s more heat loss from more exposed open water), the north-south differences in atmospheric temperatures across the Barents Sea are reduced. These conditions have been linked to <a href="https://journals.ametsoc.org/doi/abs/10.1175/jcli-d-11-00449.1">wintertime cyclones</a> travelling further south into western Europe, instead of their tendency to move eastwards towards Siberia, as well as more frequent <a href="https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2009JD013568">cold winter extremes at middle latitudes</a>.</p>
<h2>Ice and weather</h2>
<p><a href="https://journals.ametsoc.org/doi/full/10.1175/JPO-D-18-0003.1">For our recent study</a>, we looked at satellite measurements of sea ice and sea surface temperature, to determine how ocean and ice conditions have evolved between 1985 and the end of 2016. We found that prior to 2005, sea ice extended south of the Polar Front every winter, but that since 2005 this has not been the case. </p>
<p>At the same time, the sea surface temperature difference across the Polar Front has increased, with southern temperatures increasing at a faster rate than those to the north. The average between 1985 and 2004 was -1.2°C in the north and 1.5°C in the south, while between 2005 and 2016 it was -0.6°C in the north and 2.6°C in the south. Clearly, from 2005 the Barents Sea has become too warm for sea ice to exist south of the Polar Front. The question then is why is the Barents Sea getting warmer?</p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/233244/original/file-20180823-149490-irxkcl.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/233244/original/file-20180823-149490-irxkcl.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/233244/original/file-20180823-149490-irxkcl.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=386&fit=crop&dpr=1 600w, https://images.theconversation.com/files/233244/original/file-20180823-149490-irxkcl.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=386&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/233244/original/file-20180823-149490-irxkcl.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=386&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/233244/original/file-20180823-149490-irxkcl.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=485&fit=crop&dpr=1 754w, https://images.theconversation.com/files/233244/original/file-20180823-149490-irxkcl.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=485&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/233244/original/file-20180823-149490-irxkcl.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=485&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Winter-averaged sea surface temperature and sea ice extent as observed in the Barents Sea by satellites from 2005 and 2016.</span>
<span class="attribution"><span class="license">Author provided</span></span>
</figcaption>
</figure>
<p><a href="https://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-12-00266.1">Long-term oceanographic measurements</a> of water temperature and salinity near the Barents Sea Opening have shown that inflowing Atlantic Water temperatures have increased over the last 30 years, with what appears to be a <a href="https://journals.ametsoc.org/doi/full/10.1175/JPO-D-18-0003.1">small but persistent rise around 2005</a> – likely to be due to upstream changes in the North Atlantic sources (though it must be noted that our study did not explore this question). An impact of the warmer water entering the Barents Sea is a warmer atmosphere, which in turn insulates the warmer surface water allowing the Atlantic Water heat to penetrate further to the north, preventing winter sea ice formation and import (that is sea ice that has formed farther north that has drifted southwards) to the region south of the Polar Front. </p>
<p>We believe that this represents a long-term shift in the climate of the Barents Sea, a region already identified as influential on lower-latitude European weather. Furthermore, we believe that the 2005 regime shift we observed over the Barents Sea may have contributed to the increasingly frequent extreme weather events experienced over Europe in the past decade or so.</p><img src="https://counter.theconversation.com/content/100628/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Yueng-Djern Lenn currently receives and has had previous research grant funding from the Natural Environment Research Council, UK. She has also previously been supported by the National Science Foundation, USA. </span></em></p><p class="fine-print"><em><span>Benjamin Barton receives funding from the UK-France PhD programme managed by The Defence Science and Technology Laboratory (Dstl), UK and the Direction Générale de l’Armement (DGA), France. </span></em></p><p class="fine-print"><em><span>Camille Lique works for Ifremer (Institut Francais de Recherche pour l'Exploitation de la Mer). She has received funding from the UK Defence Science and Technology Laboratory (Dstl), UK and the Direction Générale de l’Armement (DGA), as well as from the French INSU-LEFE programme, the European CMEMS programme and the French 'Agence Nationale de la Recherche'. </span></em></p>Since 2005, the Barents Sea has become too warm for sea ice to exist south of the Polar Front.Yueng-Djern Lenn, Senior Lecturer in Physical Oceanography, Bangor UniversityBenjamin Barton, PhD Researcher, Bangor UniversityCamille Lique, Research scientist in physical oceanography, IfremerLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/761082017-04-13T13:58:16Z2017-04-13T13:58:16ZHeat from the Atlantic Ocean is melting Arctic sea ice further eastwards than ever before<figure><img src="https://images.theconversation.com/files/165121/original/image-20170412-25870-sfsu6n.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Sea ice in the Arctic.</span> <span class="attribution"><span class="source">Tom Rippeth</span>, <span class="license">Author provided</span></span></figcaption></figure><p>The seasonal sea-ice retreat across the Arctic Ocean is perhaps one of the most conspicuous indicators of climate change. In September 2012, a <a href="http://nsidc.org/arcticseaicenews/">new record was set</a> for the time that we have been tracking sea ice with satellites: the minimum sea ice extent was some 50% below the climatic average for that month. Four years on, and the <a href="http://nsidc.org/arcticseaicenews/">September 2016 record</a> tied with 2007 for the second lowest sea ice extent since measurements began in 1978.</p>
<p>The seasonal retreat of sea ice is largely because the atmosphere in the Arctic is heated under 24 hours of daylight in the summer, and this makes the ice melt. In the cold of the perpetual darkness of winter, the sea ice extent returns to its winter norm: the only heat available to slow sea ice growth is from winds and ocean currents moving warm air and water in from the south. </p>
<p>However, during the winter of 2016/17 the sea ice did not return to its winter norm. In fact, the sea ice extent was the <a href="http://nsidc.org/arcticseaicenews/">lowest ever recorded</a> for this time of year.</p>
<p>Though the Arctic is not exactly in the UK’s backyard, the changes in sea ice coverage are thought to be at least partly responsible for the recent <a href="http://www.nature.com/ngeo/journal/v7/n9/full/ngeo2234.html">run of severe weather events</a> experienced across the northern hemisphere. These include <a href="http://www.nature.com/ngeo/journal/v7/n12/abs/ngeo2277.html">unusually cold winter weather</a> across parts of Europe and the US, and <a href="http://advances.sciencemag.org/content/3/3/e1602751.full">deadly smogs</a> in parts of China.</p>
<p>The Arctic is warming about <a href="http://arctic.noaa.gov/Report-Card/Report-Card-2016">twice as fast</a> as the rest of the world. As the difference between atmospheric temperatures in the Arctic and mid-latitudes (<a href="https://www.spaceweatherlive.com/en/help/the-low-middle-and-high-latitude">which includes</a> the UK, part of North America, and a band of northern Europe and Asia) decreases, the speed at which weather systems (depressions) track across the Atlantic to northwestern Europe is reduced. This means that snow and rain can persist for longer, and high pressure systems are “harder to shift”, which can lead to further reductions in air quality.</p>
<h2>Warming warning</h2>
<p>The largest oceanic heat input to the Arctic comes from water that has been in the Atlantic Ocean, and has travelled through the Fram Strait and around Svalbard. This “Atlantic water” circulates around the Arctic in an anti-clockwise direction. This water is currently the <a href="http://instaar.colorado.edu/%7Emarchitt/reprints/spielhagenscience11.pdf">warmest it has been for 2,000 years</a> and now contains enough heat to completely melt the sea ice within a couple of years. </p>
<p>However, while this water is warmer than the ambient Arctic water, it is also saltier, and so heavier, too. It sits at depths of 100 to 400 metres across much of the Arctic Ocean. This means that the Atlantic water heat is insulated from the surface by a layer of lighter, colder and fresher Arctic Ocean water which sits above it.</p>
<p>Atlantic water contact with the sea surface – which then melts the sea ice impacting coverage and thickness – has <a href="http://www.nature.com/ngeo/journal/v8/n3/abs/ngeo2350.htmlhttp://www.nature.com/ngeo/journal/v8/n3/abs/ngeo2350.html">previously been restricted</a> to the region around Svalbard, where the Atlantic water enters the Arctic Ocean. However, new measurements reported by a team of international scientists have shown, for the first time, that previously insulated Atlantic water heat is now being <a href="http://science.sciencemag.org/content/early/2017/04/05/science.aai8204">stirred up to the sea surface</a>. This results in enhanced sea ice melt, much further to the east, north of Siberia. </p>
<p>We previously measured the upward Atlantic water heat flux in this region <a href="http://onlinelibrary.wiley.com/doi/10.1029/2008GL036792/">in 2007 and 2008</a>. At the time it was very modest. However, the new measurements estimate this flux to have increased by two to four times over the winters of 2013/14 and 2014/15. The result of this increase is that sea ice thickness has been reduced by between 18 and 40cm. This exceeds the impact of the atmospheric heat on sea ice melt alone (estimated to be 18cm). </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/165260/original/image-20170413-25901-lmhenr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/165260/original/image-20170413-25901-lmhenr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=413&fit=crop&dpr=1 600w, https://images.theconversation.com/files/165260/original/image-20170413-25901-lmhenr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=413&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/165260/original/image-20170413-25901-lmhenr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=413&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/165260/original/image-20170413-25901-lmhenr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=520&fit=crop&dpr=1 754w, https://images.theconversation.com/files/165260/original/image-20170413-25901-lmhenr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=520&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/165260/original/image-20170413-25901-lmhenr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=520&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A polar bear walks on the ice floes north of Svalbard.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/polar-bear-walking-across-vast-expanse-428511568?src=cTGuD0yuLx83f8SBBYu5HQ-1-3">wildestanimal/Shutterstock</a></span>
</figcaption>
</figure>
<p>The researchers attribute the change to a reduction in the vertical density gradient within the overlying Arctic water layer. The Atlantic water has moved closer to the sea surface, and created conditions much more like those found around Svalbard, where there is less sea ice. Lead researcher Igor Polyakov describes the change as the “atlantificiation” of this part of the Arctic Ocean.</p>
<p>These important new results highlight the increasing role of heat coming from the Atlantic Ocean in driving sea ice retreat in the Arctic Ocean. They are a profound sign of the planet’s changing climate, and show that there is a link between retreating Arctic sea ice and the severe weather that has been witnessed in mid-latitude countries.</p>
<p>Furthermore, they show that the impact of Atlantic water heat on sea ice is highly variable across the Arctic Ocean, with significant heat fluxes restricted to geographic “<a href="https://theconversation.com/potential-hot-spots-for-sea-ice-melting-identified-in-the-arctic-ocean-66233">hot spots</a>”. The identification of these hot spots will be key to improving how we forecast the weather in the northern hemisphere and understand how the retreat of Arctic sea ice impacts on it.</p><img src="https://counter.theconversation.com/content/76108/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Tom Rippeth receives funding from the Natural Environmental Research Council and Bangor University. He is affiliated with the Liberal Democrats. </span></em></p>The link between melting sea ice and extreme weather has been known for a while, but now it’s happening further afield.Tom Rippeth, Professor of Physical Oceanography, Bangor UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/706482016-12-21T19:03:16Z2016-12-21T19:03:16ZYes, the Arctic’s freakishly warm winter is due to humans’ climate influence<figure><img src="https://images.theconversation.com/files/151164/original/image-20161221-14203-1ksx4bd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">An Arctic iceberg, pictured in 2015. This year, ice coverage has reached record lows for the early northern winter.</span> <span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File%3AIceberg_in_the_Arctic_with_its_underside_exposed.jpg">AWeith/Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>For the Arctic, <a href="https://theconversation.com/2016-is-likely-to-be-the-worlds-hottest-year-heres-why-59378">like the globe as a whole</a>, 2016 has been exceptionally warm. For much of the year, Arctic temperatures have been much higher than normal, and sea ice concentrations have been at <a href="https://theconversation.com/climate-shenanigans-at-the-ends-of-the-earth-why-has-sea-ice-gone-haywire-69485">record low levels</a>.</p>
<p>The Arctic’s seasonal cycle means that the lowest sea ice concentrations occur in September each year. But while September 2012 had less ice than September 2016, this year the ice coverage has not increased as expected as we moved into the northern winter. As a result, since late October, Arctic sea ice extent has been at <a href="http://nsidc.org/arcticseaicenews/2016/12/arctic-and-antarctic-at-record-low-levels/">record low levels for the time of year</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/151155/original/image-20161221-13147-yynqko.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/151155/original/image-20161221-13147-yynqko.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/151155/original/image-20161221-13147-yynqko.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=468&fit=crop&dpr=1 600w, https://images.theconversation.com/files/151155/original/image-20161221-13147-yynqko.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=468&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/151155/original/image-20161221-13147-yynqko.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=468&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/151155/original/image-20161221-13147-yynqko.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=588&fit=crop&dpr=1 754w, https://images.theconversation.com/files/151155/original/image-20161221-13147-yynqko.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=588&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/151155/original/image-20161221-13147-yynqko.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=588&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Late 2016 has produced new record lows for Arctic ice.</span>
<span class="attribution"><span class="source">NSIDC</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>These record low sea ice levels have been associated with exceptionally high temperatures for the Arctic region. November and December (so far) have seen record warm temperatures. At the same time Siberia, and <a href="http://www.usatoday.com/story/news/2016/12/16/bitter-cold-grips-us-plains-new-england/95511250/">very recently North America</a>, have experienced conditions that are slightly cooler than normal.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/151158/original/image-20161221-14216-p6zlsy.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/151158/original/image-20161221-14216-p6zlsy.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/151158/original/image-20161221-14216-p6zlsy.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=497&fit=crop&dpr=1 600w, https://images.theconversation.com/files/151158/original/image-20161221-14216-p6zlsy.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=497&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/151158/original/image-20161221-14216-p6zlsy.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=497&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/151158/original/image-20161221-14216-p6zlsy.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=624&fit=crop&dpr=1 754w, https://images.theconversation.com/files/151158/original/image-20161221-14216-p6zlsy.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=624&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/151158/original/image-20161221-14216-p6zlsy.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=624&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Temperatures have been far above normal over vast areas of the Arctic this November and December.</span>
<span class="attribution"><span class="source">Geert Jan van Oldenborgh/KNMI/ERA-Interim</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Extreme Arctic warmth and low ice coverage affect the <a href="http://rsbl.royalsocietypublishing.org/content/12/8/20160198">migration patterns of marine mammals</a> and have been linked with <a href="https://www.newscientist.com/article/2112958-80000-reindeer-have-starved-to-death-as-arctic-sea-ice-retreats/">mass starvation and deaths among reindeer</a>, as well as affecting <a href="https://www.carbonbrief.org/polar-bears-and-climate-change-what-does-the-science-say">polar bear habitats</a>.</p>
<p>Given these severe ecological impacts and the <a href="https://www.theguardian.com/environment/2015/jun/01/rapid-arctic-ice-loss-linked-to-extreme-weather-changes-in-europe-and-us">potential influence of the Arctic on the climates of North America and Europe</a>, it is important that we try to understand whether and how human-induced climate change has played a role in this event.</p>
<h2>Arctic attribution</h2>
<p>Our <a href="https://wwa.climatecentral.org/">World Weather Attribution group</a>, led by <a href="https://www.climatecentral.org/">Climate Central</a> and including researchers at the <a href="http://earthsci.unimelb.edu.au/">University of Melbourne</a>, the <a href="http://www.eci.ox.ac.uk/">University of Oxford</a> and the Dutch Meteorological Service (<a href="https://www.knmi.nl/over-het-knmi/about">KNMI</a>), used three different methods to assess the role of the human climate influence on record Arctic warmth over November and December. </p>
<p>We used forecast temperatures and heat persistence models to predict what will happen for the rest of December. But even with 10 days still to go, it is clear that November-December 2016 will certainly be record-breakingly warm for the Arctic.</p>
<p>Next, I investigated whether human-caused climate change has altered the likelihood of extremely warm Arctic temperatures, using state-of-the-art climate models. By comparing climate model simulations that include human influences, such as increased greenhouse gas concentrations, with ones without these human effects, we can estimate the role of climate change in this event. </p>
<p>This technique is similar to that used in previous analyses of <a href="https://theconversation.com/the-human-role-in-our-angry-hot-summer-15596">Australian record heat</a> and the sea temperatures associated with the <a href="https://theconversation.com/great-barrier-reef-bleaching-would-be-almost-impossible-without-climate-change-58408">Great Barrier Reef coral bleaching event</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/151160/original/image-20161221-14185-4yy2jo.gif?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/151160/original/image-20161221-14185-4yy2jo.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/151160/original/image-20161221-14185-4yy2jo.gif?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=424&fit=crop&dpr=1 600w, https://images.theconversation.com/files/151160/original/image-20161221-14185-4yy2jo.gif?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=424&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/151160/original/image-20161221-14185-4yy2jo.gif?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=424&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/151160/original/image-20161221-14185-4yy2jo.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=533&fit=crop&dpr=1 754w, https://images.theconversation.com/files/151160/original/image-20161221-14185-4yy2jo.gif?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=533&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/151160/original/image-20161221-14185-4yy2jo.gif?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=533&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 November-December temperatures of 2016 are record-breaking but will be commonplace in a few decades’ time.</span>
<span class="attribution"><span class="source">Andrew King</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>To put it simply, the record November-December temperatures in the Arctic do not happen in the simulations that leave out human-driven climate factors. In fact, even with human effects included, the models suggest that this Arctic hot spell is a 1-in-200-year event. So this is a freak event even by the standards of today’s world, which humans have warmed by roughly 1°C on average since pre-industrial times.</p>
<p>But in the future, as we continue to emit greenhouse gases and further warm the planet, events like this won’t be freaks any more. If we do not reduce our greenhouse gas emissions, we estimate that by the late 2040s this event will occur on average once every two years.</p>
<h2>Watching the trend</h2>
<p>The group at KNMI used observational data (not a straightforward task in an area where very few observations are taken) to examine whether the probability of extreme warmth in the Arctic has changed over the past 100 years. To do this, temperatures slightly further south of the North Pole were incorporated into the analysis (to make up for the lack of data around the North Pole), and these indicated that the current Arctic heat is unprecedented in more than a century.</p>
<p>The observational analysis reached a similar conclusion to the model study: that a century ago this event would be extremely unlikely to occur, and now it is somewhat more likely (the observational analysis puts it at about a 1-in-50-year event).</p>
<p>The Oxford group used the very large ensemble of <a href="http://www.climateprediction.net/weatherathome/">Weather@Home</a> climate model simulations to compare Arctic heat like 2016 in the world of today with a year like 2016 without human influences. They also found a substantial human influence in this event.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/151193/original/image-20161221-14208-2uqgdn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/151193/original/image-20161221-14208-2uqgdn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/151193/original/image-20161221-14208-2uqgdn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=844&fit=crop&dpr=1 600w, https://images.theconversation.com/files/151193/original/image-20161221-14208-2uqgdn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=844&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/151193/original/image-20161221-14208-2uqgdn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=844&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/151193/original/image-20161221-14208-2uqgdn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1060&fit=crop&dpr=1 754w, https://images.theconversation.com/files/151193/original/image-20161221-14208-2uqgdn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1060&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/151193/original/image-20161221-14208-2uqgdn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1060&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Santa struggles with the heat. Climate change is warming the North Pole and increasing the chance of extreme warm events.</span>
<span class="attribution"><span class="source">Climate Central</span></span>
</figcaption>
</figure>
<p>All of our analysis points the finger at human-induced climate change for this event. Without it, Arctic warmth like this is extremely unlikely to occur. And while it’s still an extreme event in today’s climate, in the future it won’t be that unusual, unless we drastically curtail our greenhouse gas emissions. </p>
<p>As we have already seen, the consequences of more frequent extreme warmth in the future could be devastating for the animals and other species that call the Arctic home.</p>
<p><em>Geert Jan van Oldenborgh, Marc Macias-Fauria, Peter Uhe, Sjoukje Philip, Sarah Kew, David Karoly, Friederike Otto, Myles Allen and Heidi Cullen all contributed to the research on which this article is based.</em></p>
<p><em>You can find more details on all the analysis techniques <a href="https://wwa.climatecentral.org/analyses/">here</a>. Each of the methods used has been peer-reviewed, although as with the Great Barrier Reef bleaching study, we will submit a research manuscript for peer review and publication in 2017.</em></p><img src="https://counter.theconversation.com/content/70648/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Andrew King receives funding from the ARC Centre of Excellence for Climate System Science.</span></em></p>The end of 2016 has brought balmy Arctic temperatures and record low ice extent for the time of year. It’s a freak event even by modern standards, and climate models point the finger firmly at humans.Andrew King, Climate Extremes Research Fellow, The University of MelbourneLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/696542016-12-05T07:27:19Z2016-12-05T07:27:19ZWhy is China so quiet in negotiations about fisheries in the central Arctic Ocean?<p>China has become <a href="http://en.ccg.org.cn/china-expected-to-take-larger-role-in-global-governance/">more active in global governance issues</a>. Its involvement in new regulations about the changing environment of the Arctic is no exception.</p>
<p>Arctic ice is melting at an alarming rate; according to <a href="https://www.nasa.gov/feature/goddard/2016/arctic-sea-ice-is-losing-its-bulwark-against-warming-summers">a recent report from NASA</a>, the Arctic has lost almost 95% of its older ice cover since 1984. Due to this loss and other impacts of climate change, the marine ecosystems of the Arctic Ocean are also evolving. </p>
<p><a href="https://www.regjeringen.no/globalassets/departementene/ud/vedlegg/folkerett/declaration-on-arctic-fisheries-16-july-2015.pdf">It’s now widely recognised</a> that fish stocks in the Arctic Ocean may occur both within areas under current fisheries’ jurisdiction of the coastal states, and in the <a href="https://theconversation.com/historic-un-talks-could-save-the-high-seas-56449">high seas</a> portion of the central Arctic Ocean.</p>
<p>It would be a disaster for fish stocks if there’s no governance regime when fishing starts in the central Arctic Ocean. </p>
<h2>Arctic 5+5 process</h2>
<p>The coastal states of the Arctic Ocean, the so-called Arctic Five – United States, Russia, Canada, Norway and Denmark – <a href="http://www.oceanlaw.org/downloads/arctic/Ilulissat_Declaration.pdf">believe they have a stewardship role</a> in the conservation and management of Arctic marine living resources.</p>
<p>But freedom of fishing in the high seas is enshrined by the <a href="http://www.un.org/depts/los/convention_agreements/convention_overview_convention.htm">United Nations Convention on the Law of Sea</a>, which is applicable to all the world’s oceans. So, to achieve sustainable management of fisheries in the high seas portion of the central Arctic Ocean, non-Arctic states, especially high sea fishing states, such as China and the European Union, must also be involved in any regulatory efforts. </p>
<p>On July 16 2015, the Arctic Five adopted the Declaration Concerning the Prevention of Unregulated High Sea Fishing in the Central Arctic Ocean, or the <a href="https://www.regjeringen.no/globalassets/departementene/ud/vedlegg/folkerett/declaration-on-arctic-fisheries-16-july-2015.pdf">Oslo Declaration</a>. It acknowledges the interest of other states in preventing unregulated high seas fisheries in the central Arctic Ocean and starts a so-called “broader process” of developing fisheries management measures for the central Arctic Ocean with non-Arctic states. </p>
<p>As a result, China, the EU, Iceland, Japan and the Republic of Korea – the five leading non-Arctic fishing states – were invited to help develop a regional fisheries organisation or arrangement for the central Arctic Ocean.</p>
<p>Known as the Arctic 5+5, the group held its first meeting on fisheries in <a href="http://www.state.gov/e/oes/rls/pr/250352.htm">Washington</a> in December 2015. A series of follow-up meetings has been held since in <a href="https://www.afsc.noaa.gov/Arctic_fish_stocks_fourth_meeting/pdfs/Chairman's_Statement_from_Washington_Meeting_April_2016-2.pdf">Washington (again)</a>, <a href="http://naalakkersuisut.gl/%7E/media/Nanoq/Files/Attached%20Files/Fiskeri_Fangst_Landbrug/Eng/Chairmans%20Statement%20from%20Iqaluit%20Arctic%20HS%20Meeting%20July%202016.pdf">Iqualuit in Canada</a> and <a href="http://arcticjournal.com/press-releases/2733/meeting-high-seas-fisheries-central-arctic-ocean">Torshavn, in the Faroe Islands</a>. </p>
<p>During the last meeting in Faroe Islands, all delegations reaffirmed their commitment to prevent unregulated commercial high seas fishing in the central Arctic Ocean. They also committed to promoting the conservation and sustainable use of living marine resources, and to safeguard healthy marine ecosystems in the area. </p>
<p>But a formal agreement has not yet been reached; another meeting will be held in Iceland next year.</p>
<h2>A tale of two poles</h2>
<p>As the world’s <a href="http://www.fao.org/3/a-i5555e.pdf">largest fishing nation</a>, China now has global interests from West Africa to Antarctica. </p>
<p>Until 2015, the country was openly opposed to <a href="https://theconversation.com/how-china-came-in-from-the-cold-to-help-set-up-antarcticas-vast-new-marine-park-67911">the establishment of marine protected areas in Antarctica</a> at the Annual Meetings of Commission for Conservation of Antarctic Marine Living Resources (CCAMLR), partly due to its krill fishing interest in the Southern Ocean.</p>
<p>But it has, so far, been very quiet in the central Arctic Ocean fisheries negotiations. Why is China’s behaviour in the two poles so dramatically different? </p>
<h2>A weak Arctic connection</h2>
<p>China is undoubtedly interested in the Arctic, especially the potential for developing resources in the region. The country started <a href="http://www.chinadailyasia.com/chinafocus/2016-11/16/content_15527219_2.html">building its first research station in Iceland</a> to study the northern lights recently, sign-posting its possible Arctic ambitions. </p>
<p>But the fact remains that China’s capacity to participate in Arctic affairs is still weak. It has just one Arctic research station (<a href="http://www.chinare.gov.cn/en/index.html?pid=stations&st=yellow">Yellow River</a>) in the Norwegian archipelago of Svalbard, compared to four research stations in Antarctica (<a href="http://en.people.cn/n/2015/0112/c98649-8834787.html">a fifth</a> is on its way). </p>
<p>Only recently, in the summer of 2012, did the Chinese Icebreaker Xue Long sail across the Northern Sea route along Russian Coastal line. Chinese scientists entered into Russian Exclusive Economic Zone of the Arctic Ocean for the first time in August 2016, while conducting their first <a href="http://arctic.ru/international/20160209/296401.html">joint research with Russian colleagues</a>. </p>
<p>China may simply not be confident enough to provide proposals based on its own scientific data in the fisheries negotiation. </p>
<h2>Part of the conversation</h2>
<p>No fishing is happening in the central Arctic Ocean yet. The current negotiations are merely about emerging interest, which probably means less influence from the industry on the Chinese delegation. </p>
<p>The fisheries industry usually plays a vital role in China’s policy process regarding fisheries. The Chinese delegation to the annual meeting of the CCAMLR and other regional fisheries management organisations, for instance, are <a href="https://www.ccamlr.org/en/system/files/e-cc-xxxv-v2.pdf">full of fisheries officials, scientists and industry representatives</a>. </p>
<p>Indeed, China’s participation in the central Arctic Ocean fisheries negotiations seems to be more symbolic, an attempt to not be left behind. At this point at any rate, it seems China is generally satisfied with the fact of being invited to attend the meetings. </p>
<h2>Gaining trust</h2>
<p>China has been working hard to gain the trust of the five Arctic states to facilitate collaboration in resources development in the region. </p>
<p>China finally entered into the “Arctic Club” in 2013 by <a href="https://oaarchive.arctic-council.org/bitstream/handle/11374/93/MM08_Final_Kiruna_declaration_w_signature.pdf?sequence=1&isAllowed=y">becoming an observer of the Arctic Council</a>, the most important regional forum for discussion of Arctic issues. </p>
<p><a href="http://www.arctic-council.org/index.php/en/about-us/arctic-council/observers">The criteria set by the Arctic Council to determine observer status</a> include the recognition of Arctic states’ sovereignty, sovereign rights and jurisdiction in the Arctic; and the recognition that an extensive legal framework applies to the Arctic Ocean including, notably, the Law of the Sea. Observers must recognise that this framework provides a solid foundation for responsible management of the ocean. </p>
<p>Its accession to the group suggests China has decided to embrace rather than fundamentally challenge the current regime in the Arctic. </p>
<p>Its quiet voice in the central Arctic Ocean fisheries negotiations is another example of the country showcasing its willingness to be a collaborative partner in the region. </p>
<p>China is likely to continue on this path in the foreseeable future, with strong interests and growing capacity in the fast-changing Arctic region.</p><img src="https://counter.theconversation.com/content/69654/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Nengye Liu 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>China has been very quiet in negotiations over fisheries regulations for the central Arctic Ocean. Why is the country’s behaviour there so dramatically different from what it pursues in Antarctica?Nengye Liu, Senior Lecturer in Law, University of New EnglandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/256212014-04-14T14:50:16Z2014-04-14T14:50:16ZTitanic twist: 1912 wasn’t a bad year for icebergs after all<p>At 11.40pm local time on the cold, moonless night of 14 April 1912, the crow’s nest lookouts on board the RMS Titanic sighted a large iceberg only 500m ahead. Despite quick action, the iceberg still struck the ship aft of the bows and water flooded into the ship across several compartments. In little more than two and a half hours the Titanic sunk, taking with her 1,514 lives. </p>
<p>The dramatic and sudden sinking of the ship that was touted to be unsinkable provoked a great search over the next 100 years to understand how the fateful crash happened. And whether or not there was a greater risk from the number of icebergs in 1912 has been a major cause for debate.</p>
<p>Theories linking exceptional iceberg numbers to effects such as <a href="http://onlinelibrary.wiley.com/doi/10.1002/j.1477-8696.2000.tb04034.x/abstract">sunspots</a> or <a href="http://www.txstate.edu/news/news_releases/news_archive/2012/March-2012/Titanic030512.html">extreme tides</a> on the coast of Greenland have perpetuated the idea that 1912 was an exceptional year for icebergs, stacking the cards against the Titanic on her maiden voyage. Indeed, ships travelling through the northwest Atlantic in the days leading up to the tragedy did exchange a number of reports of ice. </p>
<p>But our <a href="http://onlinelibrary.wiley.com/enhanced/doi/10.1002/wea.2238">recent research</a>, using the iceberg records of the International Ice Patrol and an iceberg-ocean model, counters this accepted view. We’ve found that the number of icebergs in the region was neither exceptional nor unprecedented.</p>
<p>Following the Titanic disaster, the <a href="http://www.navcen.uscg.gov/?pageName=IIPHome">International Ice Patrol</a> was established to monitor ice hazards and warn ships in the northwest Atlantic. One way they measure the iceberg hazard is by reporting the number of icebergs seen south of 48°N, a latitude extending out into the Atlantic from the south of Newfoundland. This recording has continued since 1913, and ship reports prior to this gives data reaching back to 1900 of ice in the area that the Titanic sank. </p>
<p>In 1912, 1,038 icebergs were reported crossing this latitude circle. In a record that varies between no icebergs and well over two thousand a year, this qualifies as a significant number. But there are several years in surrounding decades with similar numbers, including five years with at least 700 icebergs crossing the region between 1901 and 1920. The iceberg risk in 1912 then, was significant, but not unprecedented, and has been much greater in recent decades.</p>
<h2>Source of the titanic iceberg</h2>
<p>Our iceberg-ocean model also allows us to suggest a likely origin for the iceberg that collided with the Titanic. The longstanding view of iceberg movement in the northwest Atlantic is that icebergs from successive glaciers feed into the ocean current. Following it, they flow south along the east Greenland coast and then north along the west Greenland coast, finally circling Baffin Bay and heading south along the Labrador coast towards the Atlantic shipping lanes.</p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/46368/original/rz27gz8g-1397476169.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/46368/original/rz27gz8g-1397476169.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=495&fit=crop&dpr=1 600w, https://images.theconversation.com/files/46368/original/rz27gz8g-1397476169.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=495&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/46368/original/rz27gz8g-1397476169.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=495&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/46368/original/rz27gz8g-1397476169.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=622&fit=crop&dpr=1 754w, https://images.theconversation.com/files/46368/original/rz27gz8g-1397476169.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=622&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/46368/original/rz27gz8g-1397476169.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=622&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Route taken by Arctic icebergs toward Atlantic shipping lanes.</span>
<span class="attribution"><span class="source">Grant Bigg</span></span>
</figcaption>
</figure>
<p>There is no way to say from which point along this long journey the infamous iceberg might have originated – it suddenly appeared out of the night and then disappeared after colliding with the Titanic. But our model allows us to use the winds and currents of the time to give the likely origins and routes for icebergs reaching the vicinity of the Titanic sinking in mid-April 1912. </p>
<p>It is very likely that the Titanic iceberg calved (broke off) from a glacier in one of the fjords of the southwest corner of Greenland during the late summer or early autumn of 1911 and took a more direct path, across the northern Labrador Sea, to its rendezvous with the ship.</p>
<p>Placing total faith in model results without supporting observations is problematic. And, even the model suggests there is a small possibility the iceberg originated from further north, in Baffin Bay, so the question of the Titanic iceberg’s origin can never be resolved with absolute certainty. But descriptions of the iceberg from survivors and the fact that five sixths of the icebergs modelled as passing 48°N latitude calved from southwest Greenland in 1912 support our model.</p>
<h2>Icebergs ahead</h2>
<p>More localised iceberg models are used on a regular basis by the International Ice Patrol to track icebergs in the NW Atlantic today, in combination with satellite and radar data. Even though there have been years of much greater iceberg numbers in the recent past, this constant monitoring has meant the risk to shipping is now much reduced. </p>
<p>Icebergs are still a threat, however, and the risk in regions without this constant monitoring is significant. As recently as 2007, the cruise ship <a href="http://www.theguardian.com/world/gallery/2007/nov/23/antarctica">MV Explorer sank</a> after a collision with an iceberg in the Weddell Sea, off Antarctica and collisions elsewhere occur from time to time. </p>
<p>Indeed, icebergs will remain a real risk for years to come. Their number is likely to increase as Arctic glaciers respond to global warming and the sea-ice retreats. With shipping routes planned for the Arctic and the construction of coastal installations, monitoring iceberg hazards continues to be important to prevent more titanic disasters in the future.</p><img src="https://counter.theconversation.com/content/25621/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Grant Bigg receives funding from the Natural Environment Research Council.</span></em></p>At 11.40pm local time on the cold, moonless night of 14 April 1912, the crow’s nest lookouts on board the RMS Titanic sighted a large iceberg only 500m ahead. Despite quick action, the iceberg still struck…Grant Bigg, Professor in Earth Systems Science, University of SheffieldLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/197312013-10-31T13:09:03Z2013-10-31T13:09:03ZIf next summer is rained off, blame the melting Arctic<figure><img src="https://images.theconversation.com/files/34179/original/wfpy9j2s-1383221427.jpg?ixlib=rb-1.1.0&rect=0%2C228%2C1001%2C718&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Another great British summer.</span> <span class="attribution"><span class="source">[Duncan]</span></span></figcaption></figure><p>Most people saw the warm dry weather from June to September as a welcome, but freak, occurrence. Because, as anyone who invested in floaty dresses, barbecues or expensive sunglasses in previous years will know, recent summers in Britain and north-western Europe have been unusually wet.</p>
<p>From 2007 to 2012, sunshine has been lower and rainfall higher than average, with 2012 - the summer that never was - the wettest for more than a century. With rainfall 80% higher than average, there were frequent floods, substantial damage to property, deaths and serious consequences for farming and tourism.</p>
<p>At the same time, during these summers, the amount of Arctic sea ice was very low. The summers between 2007 and 2012 were the six lowest years on record, with 2012 an all-time low. Could melting sea ice and wet summers be related?</p>
<p>In my <a href="http://iopscience.iop.org/1748-9326/8/4/044015/article">recent study</a> I used a climate model to investigate what impact the loss of Arctic sea ice has on weather patterns over Europe. The amount of sea ice cover in the model was changed in a controlled manner while other factors known to influence European weather were held constant. This allowed me to isolate and measure the affects of melting sea ice.</p>
<p>The model confirmed that when sea ice cover shrunk, the UK and north-western Europe experienced wetter summers. The pattern of rainfall anomalies in the model looked very similar to those observed in recent years. It seems reasonable to conclude that the loss of Arctic sea ice is one contributing factor in these washed-out summers.</p>
<h2>Jet stream</h2>
<p>Another factor that strongly influences the quality of European summers is the position of the <a href="http://www.metoffice.gov.uk/learning/wind/what-is-the-jet-stream">jet stream</a>. Jet streams are currents of strong winds, around 10km up in the atmosphere. Generally these winds blow from west to east, carrying weather systems and rain with them. During the summer, the jet stream normally lies between Scotland and Iceland, so heavy weather is carried through the Atlantic north of the British Isles. But when the jet stream shifts south, as it did for prolonged periods during the summers between 2007 and 2012, that unseasonable wet weather makes landfall in the UK.</p>
<p>The model confirmed that melting sea ice causes the jet stream to shift further south than normal, increasing the frequency of cloudy, cool and wet summers over north-western Europe. In contrast, Mediterranean Europe experienced drier conditions as sea ice was reduced.</p>
<h2>The bigger picture</h2>
<p>However, missing sea ice is only partially to blame for these soggy summers. A <a href="http://www.nature.com/ngeo/journal/v5/n11/full/ngeo1595.html">previous study</a> showed how European rainfall is influenced by a slow natural cycle of warming and cooling in the uppermost levels of the North Atlantic. Since the late 1990s, the Atlantic has been in the warm phase of that cycle - known as the <a href="http://www.cgd.ucar.edu/cas/catalog/climind/AMO.html">Atlantic Multidecadal Oscillation</a> - which is thought to bring with it greater risk of wet summers. So the combination in recent years of low Arctic sea ice and a warmer Atlantic have further increased the odds of wet summers. Together these two factors help explain our lack of sunshine and booming welly sales through the last few summers.</p>
<p>But there is one other factor that cannot be ignored: the natural, chaotic and completely unpredictable element of weather systems - not least in Britain, which has always had a more than average amount of unpredictable weather. Atmospheric variability can, and often does, exceed the influence of Arctic sea ice. Melting sea ice may increase the odds of a wet summer, but it will not lead to a wet summer every year. Buying extra lottery tickets increases your chances of winning, but clearly does not guarantee success.</p>
<p>This summer just gone is perhaps a timely reminder - despite warmer-than-average sea surface temperatures in the Atlantic and lower-than-average Arctic sea ice cover, summer 2013 turned out to be quite warm, dry and sunny. The Met Office reports that the UK’s 2013 summer was [the driest since 2003](http://www.metoffice.gov.uk/climate/uk/2012/summer.html](http://www.metoffice.gov.uk/climate/uk/2012/summer.htm).</p>
<h2>Future implications</h2>
<p>What does this all mean for future summers? Will there be opportunity to wear those dresses again before the moths get to them? The Atlantic Ocean will return to its cool phase in the next decade, which is expected to bring with it warmer and drier summers. But Arctic sea ice on the other hand is expected to <a href="http://www.theguardian.com/uk/2012/jul/18/wet-weather-boosts-cinemas-indoor">continue melting</a>, favouring potentially wetter summers. The outcome of this climate tug-of-war is uncertain and hard to predict - and in that respect, it’s business as usual for the British weather.</p><img src="https://counter.theconversation.com/content/19731/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>James Screen receives funding from the Natural Environment Research Council, UK.</span></em></p>Most people saw the warm dry weather from June to September as a welcome, but freak, occurrence. Because, as anyone who invested in floaty dresses, barbecues or expensive sunglasses in previous years will…James Screen, Research Fellow, Exeter Climate Systems Group, University of ExeterLicensed as Creative Commons – attribution, no derivatives.