The Paris Agreement could provide a forum for international cooperation on risky, planet-scale engineering to cool the Earth.
It's increasingly likely that at some point, the world's nations will need to broach the fraught discussion of geoengineering. The UN climate accord was a natural forum to do it.
Sherman Cahal / shutterstock
Scientists want to exploit a natural process of carbon storage.
pisaphotography / shutterstock
It's a daunting technical challenge. But the key question is whether such engineering is socially acceptable.
We still don’t know enough about questions such as where the tipping points are for Arctic ice melt.
Christine Zenino/Wikimedia Commons
The Paris agreement has given us some solid targets to aim for in terms of limiting global warming. But that in turn begs a whole range of new scientific questions.
Will the world resort to ‘solar radiation management’ to slow the Earth’s heating?
Yes, we blunt the effects of climate change by getting off fossil fuels. But countries' most ambitious targets imply use of climate engineering schemes – and that discussion should be done in public.
Clearing mulga woodland in Queensland to open up land for cattle during drought.
We're going to have to adapt to climate change, but some of the options on the table could do more harm than good if they destroy the ecosystems that protect us.
Geoengineering could help regions affected by climate change deal with the problem.
Patrick Pleul / EPA
Sometime soon we'll need to take more carbon out of the atmosphere than we emit – but how?
Volcanoes produce large amounts of a gas that interacts with air to produce sulfate aerosols, which act as tiny mirrors in the atmosphere to reflect sunlight – and heat.
Blocking the sun by injecting tiny particles in the atmosphere – called solar geoengineering – can lower the Earth's temperature but has some real costs. Economists run the numbers.
Volcanic eruptions lead to global cooling – could we mimic them?
Beawiharta Beawiharta / Reuters
Though climate engineering has lots of problems we need to do more than simply cut emissions.
Spot the opera house.
The dust storm that turned Sydney red in 2009 triggered plankton blooms in the Tasman Sea, demonstrating how we might fertilise the ocean to take up more carbon dioxide.
Ittiz / wiki
Imagine building a dam across the Strait of Gibraltar and draining the Mediterranean in order to generate vast amounts of hydroelectricity and create fertile new lands.
Geoengineering the climate may be more palatable if it supports natural processes.
Tree planting image from www.shutterstock.com
No matter how much we reduce greenhouse gas emissions, it will not be enough to keep global warming below 2C. Does this mean we should give up? Not at all.
Replanting forests is one way to remove carbon dioxide from the atmosphere. This is a site in China.
New research shows that we'll have to remove carbon from the atmosphere for any chance of keeping warming below 2C.
Trees remove carbon dioxide naturally: can we do better?
Coconino National Forest
Like it or not we are going to have to figure out how to suck lots of carbon out of the atmosphere.
Few of Nepal’s houses use modern anti-earthquake engineering.
Diego Azubel / EPA
Encasing old buildings in cheap plastic packaging mesh can keep them upright for long enough for those inside to escape.
If we’re going to mess with the weather, better know what we’re doing first.
The publication of a hefty two-volume report on geoengineering by the US National Research Council represents a marked shift in the global debate over how to respond to global warming. To date, the debate…
Just mimic this a few dozen times and we’ll be right. Right?
Taro Taylor/Wikimedia Commons
Some people might argue that the greatest moral challenge of our time is serious enough to justify deliberately tampering with our climate to stave off the damaging effects of global warming. Geoengineering…
The engineers’ realm extends far beyond construction – it bridges the gap between research and practical application.
AUSTRALIA 2025: How will science address the challenges of the future? In collaboration with Australia’s chief scientist Ian Chubb, we’re asking how each science discipline will contribute to Australia…
The future is in your hands, tread carefully.
This is a transcript of a speech given at the British Science Festival in Newcastle on September 12. It’s always a pleasure to speak at the British (Science) Association, but there are two special reasons…