[Ed. – Personally, I like the one about scattering gemstones. Where’s Mel Brooks when we need him?]
Some proposals are uncontroversial, such as using charcoal to lock carbon dioxide into soil or scattering carbon-absorbing gemstones. Richard Branson, the billionaire chairman of Virgin Group Ltd., has offered a $25 million prize for the best solution in the field known as geoengineering.
Other ideas to cool the planet have scientists worried about unintended consequences. There are proposals, untested at scale and with uncertain costs, to block the sun’s rays with airborne particles or seed the oceans with carbon-absorbing iron. That they’re even being considered reveals both frustration over government inaction and skepticism that policy alone will solve the problem.
“For the last 20 to 30 years, governments, at the back of their minds, have assumed that mitigation is the main way forward,” said Mark Maslin, a fellow at the U.K.’s Royal Geographical Society. Researchers now realize that the planet needs “other urgent ways of dealing with CO2.” …
There is a sense of urgency. Researchers are seeking to limit warming to 2 degrees Celsius (3.6 degrees Fahrenheit) from pre-industrial times.
“To achieve that we will have to actually do some sort of geoengineering,” Maslin said.
Global surface temperatures have already risen about 0.85 degrees Celsius since 1880, according to a 2014 UN report. The researchers found that while the unintended consequences of manipulating the climate may be significant, “some basic inquiry does seem appropriate.”