“The amount of material we would release is tiny… For example, if we tested sulphates, we would put less material into the stratosphere than a typical commercial aircraft does in one minute.” Photograph: ISS/Nasa
David W Keith and Gernot Wagner Wednesday 29 March 2017 04.30 EDT
Models suggest solar geoengineering could reduce climate change and our independently assessed studies are vital to understanding its full potential
Even if the world were to cut emissions to zero tomorrow, global temperatures and sea levels would rise for decades. If our roll of the climate dice is unlucky, they could rise for centuries. It is in this context that some climate researchers have begun to reluctantly take seriously ideas first proposed in the 1960s: the possibility of using solar geoengineering to help restore the world’s climate, alongside aggressive actions to reduce greenhouse-gas (GHG) emissions to zero and below.
Fear of solar geoengineering is entirely healthy. Its mere prospect might be hyped by fossil fuel interests to thwart emissions cuts. It could be used by one or a few nations in a way that’s harmful to many. There might be some yet undiscovered risk making the technology much less effective in reality than the largely positive story told by computer models.
Yet that healthy fear can distort discussion in unhealthy ways. A reader glancing at recent coverage in the Guardian, especially a piece by Martin Lukacs, might assume we were capitalistic tools of Donald Trump, eager to geoengineer the planet, democracy and justice be damned.