More and more prominent climate and energy scientists have expressed support for studies into various geoengineering approaches, such as sequestering carbon in the ocean by growing large swaths of algae.
And in the last 6 months, top institutions have launched efforts to study the subject. The U.K. Royal Society has a study due out in the summer; the U.S. National Academies is hosting a workshop in the summer as well. The semisecret JASONS group will be discussing the topic in a session in the coming months; the British Parliament has a commission examining whether the U.K. government should fund research into the matter.
No mainstream scientists are advocating using geoengineering techniques right now, but more and more researchers feel that a worsening picture of global climate change warrants studying such interventions in case of a climate emergency in the future. "We don't want to do geoengineering, but we're in increasingly dire straits," says climate expert Michael MacCracken of the Climate Institute in Washington D.C., who has advocated publicly for research into geoengineering. He says that DARPA support for such work "could be good for the field."
But other scientists worry that military support for the work could create the public impression that the work was meant to harm. “The last thing we need is to have DARPA developing climate-intervention technology,” says Caldeira. He says he agreed to go to the meeting “to try to get DARPA not to develop geoengineering techniques. Geoengineering is already so fraught with social, geopolitical, economic, and ethical issues; why would we want to add military dimensions?” He adds, however, that he would support DARPA studying the topic in case an adversary were to use it.