‘New research indicates that hacking the atmosphere — pumping microscopic particles into the stratosphere or clouds to block sunlight and offset global warming caused by greenhouse gases — is imminently possible. The problem is we could never, ever stop doing it.
Climate scientists Damon Matthews of Concordia University and Ken Caldeira of Stanford ran the numbers on atmospheric geo-engineering through a climate simulation and found that while cranking out carbon dioxide at business-as-usual rates we can geo-engineer our way back toward pre-industrial temperatures in short order, reaching 1900 levels in about five years. Not only that, it would be fairly cheap and easy to do.
Pumping 20 to 25 liters of aerosols per second to keep enough particles in the stratosphere would cool temperatures, causing the planet’s carbon sinks to suck more carbon dioxide out of the atmosphere.
“That kind of flow rate can be handled by a single fire hose,” said Caldeira. “For something like $100 million a year you could probably keep a hose in the stratosphere suspended by an array of balloons with pumps along the way.”
The problem is what happens if we stop short or screw it up.’