As the climate continues to change and humans are implicated as the cause, the one major back up plan has been geoengineering—somehow devising a way to reduce the impacts of a warming world. Avoiding it al together would be the simplest response, just by turning down the world’s furnace. Collectively we burn some 83 million barrels of oil each day, not to mention coal and natural gas, production of which are sharply increasing. But as the will remains elusive to get the biggest polluters to agree to knock it off, environmental advocates have started to consider Plan B—geoengineering—the new Plan A.
The leading method is known as stratospheric aerosol injection (SAI) and effectively shoots particles into the stratosphere that act as tiny mirrors. They reflect sunlight back into space, keeping heat out before it can warm the Earth. As long as there are particles in the stratosphere, we on Earth can burn fossil fuels for hundreds of years (or until they simply run out). It’s not a terrible idea. Being told you can still pollute and emit without consequences is like being told that you can eat nothing but junk food and avoid exercise and still not get fat. It sounds great, but it comes with a nagging feeling that it’s probably not sustainable.
Indeed it isn’t. A new paper from the Global Catastrophic Risk Institute looks at the long term demands of SAI engineering. Everything’s fine as long as you keep injecting particles. But the moment you stop, the particles start to settle back to earth and the planet would see drastic warming—much faster than on the gradual path we’re on. A global catastrophe like a health pandemic, world war, or, god forbid, an asteroid strike, could cripple humanity’s ability to keep injecting particles upward. The sudden and dramatic warming of the planet would provide a quick second punch when the world is already on its knees. It’s not a very uplifting thought, yet it does underscore the truism that you can never truly Scotch-tape your problems away. When you’ve been eating too much junk food, the most effectively strategy is always frustratingly simple: change your habits.