With the planet facing potentially severe impacts from global warming in coming decades, a government-sponsored scientific panel called for more research on geoengineering – technologies to deliberately intervene in nature to counter climate change.
The panel said earlier this week the research could include small-scale outdoor experiments, which many scientists say are necessary to better understand whether and how geoengineering would work.
Some environmental groups and others say such projects could have unintended damaging effects, and could set society on an unstoppable path to full-scale deployment of the technologies.
But the National Academy of Sciences panel said that with proper governance, which it said needed to be developed, and other safeguards, such experiments should pose no significant risk.
In two reports, the panel – which was supported by NASA and other federal agencies, including what the reports described as the “U.S. intelligence community” – noted that drastically reducing emissions of carbon dioxide and other greenhouse gases was by far the best way to mitigate the effects of a warming planet.
But the panel, in making the case for more research into geoengineering, said, “It may be prudent to examine additional options for limiting the risks from climate change.”
“The committee felt that the need for information at this point outweighs the need for shoving this topic under the rug,” Marcia K. McNutt, chairwoman of the panel and the editor in chief of the journal Science, said at a news conference in Washington.
Geoengineering options generally fall into two categories: capturing and storing some of the carbon dioxide that already has been emitted so that the atmosphere traps less heat, or reflecting more sunlight away from the Earth so there is less heat to start with.
The panel said that while the first option, called carbon dioxide removal, was relatively low risk, it was expensive, and even if it were pursued on a planetwide scale, it would take many decades to have a significant impact on the climate. But the group said research was needed to develop efficient and effective methods to both remove the gas and store it so it remains out of the atmosphere indefinitely.
The second option, called solar radiation management, is far more controversial. Most discussions of the concept focus on the idea of dispersing sulfates or other chemicals high in the atmosphere where they would reflect sunlight.
The process would be relatively inexpensive and should quickly lower temperatures, but it would have to be repeated indefinitely and would do nothing about another carbon dioxide-related problem: the acidification of oceans.
