Climate change experts argue for international geoengineering effort

Internationally coordinated research and field-testing on 'geoengineering' the planet's atmosphere to limit risk of climate change should begin soon along with building international governance of the technology, say scientists from the University of Calgary and the United States.

Collaborative and government-supported studies on solar-radiation management, a form of geo-engineering, would reduce the risk of nations' unilateral experiments and help identify technologies with the least risk, says U of C scientist David Keith, in an article published in the Jan. 27 online edition of Nature. Co-authors of the opinion piece are Edward Parson at the University of Michigan and Granger Morgan at Carnegie Mellon University.

"Solar-radiation management may be the only human response that can fend off rapid and high-consequence climate change impacts. The risks of not doing research outweigh the risks of doing it," says Keith, director of the Institute for Sustainable Energy, Environment and Economy's energy and environmental systems group and a professor in the Schulich School of Engineering.

Solar-radiation management (SRM) would involve releasing megatonnes of light-scattering in the to reduce Earth's absorption of solar energy, thereby cooling the planet. Another technique would be to release particles of sea salt to make low-altitude clouds reflect more solar energy back into space.

SRM should not take the place of making deep cuts in industrial and taking action to adapt to , Keith and his American colleagues stress. However, they say: "We must develop the capability to do SRM in a manner that complements such cuts, while managing the associated environmental and political risks."

The scientists propose that governments establish an international research budget for SRM that grows from about $10 million to $1 billion a year between now and the end of 2020. They urge that research results be available to all and risk assessments be as transparent and international as possible to build sound norms of governance for SRM.

Long-established estimates show that SRM could offset this century's predicted global average temperature rise more than 100 times more cheaply than achieving the same cooling by cutting emissions, Keith notes. "But this low price tag raises the risks of single groups acting alone, and of facile cheerleading that promotes exclusive reliance on SRM."

SRM would also cool the planet quickly, whereas even a massive program of carbon dioxide emission cuts will take many decades to slow global warming because the CO2 already accumulated in the atmosphere will take many years to naturally break down. The 1991 eruption of Mount Pinatubo, for example, cooled the planet by about 0.5 degrees Celsius in less than a year by injecting sulphur into the stratosphere.

But a world cooled by managing sunlight will present risks, the scientists note. The planet would have less precipitation and less evaporation, and monsoon rains and winds might be weakened. Some areas would be more protected from temperature changes than others, creating local 'winners' and losers.'

"If the world relies solely on SRM to limit (global) warming, these problems will eventually pose risks as large as those from uncontrolled emissions," they warn.

Field tests of SRM are the only way to identify the best technologies and potential risks, Keith says. He and the American scientists propose carefully controlled testing that would involve releasing tonnes - not megatonnes - of aerosols in the stratosphere and low-altitude clouds.

"If SRM proves to be unworkable or poses unacceptable risks, the sooner we know the less moral hazard it poses; if it is effective, we gain a useful additional tool to limit climate damages.".

Responsible management of climate risks requires deep emission cuts and research and assessment of SRM technologies, the scientists say. "The two are not in opposition. We are currently doing neither; action is urgently needed on both."

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Jan 27, 2010
AGW nutjobs are going to destroy the earth.

Jan 27, 2010
Strange it should come from the U of C ..... that is a hot bed of (oil company financed) denier psudo-science from a bunch called "The Friends of Science".

Jan 27, 2010
Any person who still believes in AGW is either ignornant of the facts, or just a nutjob.

Jan 27, 2010
These geoengineering scenarios appear to be nothing more than end-runs around the central problem. Why spend billions or trillions of dollars on projects of doubtful efficacy, when there is already technology available to accomplish the same end? Renewable energy, biofuels/catalysis, biochar, et c- this is just advance for the typical corporate money grab.

Jan 27, 2010
Any sane person here still believes in AGW? I have more information about how scientists hid climate data.


Jan 28, 2010
I'm more afraid we would botch any geoengineering either due to political compromises, or just plain human-error (albeit on a massive scale).

I want to see real scientific work done by apolitical groups.

There will always be those that stand staunchly on one side or the other. Those that scream "Global warming is here and we are hiding it!" and those who also scream "Global warming is a hoax!" may never be persuaded from their beliefs, but real scientific discourse is needed.

I don't know who's number are right (if any). I just know that we need to do a better job at getting these numbers in a way that is not politically biased.

Jan 28, 2010
These geoengineering scenarios appear to be nothing more than end-runs around the central problem. Why spend billions or trillions of dollars on projects of doubtful efficacy, when there is already technology available to accomplish the same end? Renewable energy, biofuels/catalysis, biochar, et c- this is just advance for the typical corporate money grab.

While the geoengineering of a chaos driven system is just plain brain-dead, these alternatives are no more economically feasible. They would produce an unreliable (in the case of wind and solar) that would cost a minimum of ten times the cost of current electrical generation.
It's like CFLs, sure they use less electricity than incandescent or halogen lights but they have a higher environmental impact (mercury and electronics) than incandescent bulbs and, in my experience, are not lasting that much longer (shoddy manufacturing) while costing twice as much.

Jan 31, 2010
If they start "geoengineering" I think I'll find a nice deep hole to crawl into. Maybe then I'll be safe from the "experts".

Feb 01, 2010
It is irreponsible to act without some expectation of outcome. For geoengineering actions, we would need a very precise expectation of outcome. We are probably 100 years away from developing a reliable climate model that could be used for doing virtual geoengineering experiments.

Feb 01, 2010
It seems the AGW "Crazyplane" is about to reach takeoff speed! Too bad it's running out of tarmac.

If we only spend 100 Quintillion dollars, we can actually FORCE weather to behave like our models for 1990 climate!

If any of these idiots actually attempts to damage the ecosystem with these kind of ideas, they need to be dealt with militarily.

Can you imagine the horrible aftermath of some outlandish "solar aerosol" experiment gone wrong? What if these bozos damage the plankton growth cycle of the oceans? If they think AGW is a problem, wait until the entire ecosystem comes crashing down because they meddled with nature in ignorance. Not only will that ignite a global resource war as the nations began to starve, but the planet would take hundreds or even thousands of years to recover.

Feb 01, 2010
I'm surprised to hear David Keith espousing this idea. I associate him with carbon capture and sequestration. Has he abandoned that tack and chosen a new heading?

Feb 04, 2010
Technologically, we can do it.
Socially, we're not evolved enough to do it.

When a country develops nuclear technology everyone takes pause due to the destruction they could cause.

Just imagine the amount of destruction that someone could cause by perverting a geoengineering project.

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