The Associated Press has a fascinating, must-read report today about an international gathering of scholars convened last month by Britain’s Royal Society to consider the last-ditch prospect of preventing global warming by developing ways of blocking out the sun.
The meeting brought together 80 earth and atmospheric scientists, legal and political scholars and philosophers to consider ways it could be done, possible side effects, political fallout and moral implications of massive “geo-engineering” projects. It was co-sponsored by a German environmental group and a federation of developing-world scientific societies,
The organizing premise was that the international community won’t be able to summon the political will to stop global warming before it reaches catastrophic levels, in large part because of U.S. rejection of the underlying scientific finding that the danger exists. The sun-blocking ideas are in the nature of desperate measures, a sort of literal Hail Mary pass.
Some possible technologies are purely speculative, like putting giant mirrors into orbit. Others are already being tested experimentally, including salting the upper atmosphere with sulfate particles that would reflect the sun’s rays back into space. Engineers at the University of Bristol are experimenting with the idea of pouring sulfates into space via a gigantic hose held up by balloons. They worry, though, that this would also reduce the ozone layer and raise the threat of cancer from ultra-violet radiation.
Another idea, soon to be tested by scientists at the Woods Hole center in Massachusetts, is to add iron to the oceans in order to increase their ability to suck carbon dioxide out of the atmosphere.
One of the worries is that if any of these shows promise it would simply give politicians another excuse to delay action against carbon emissions.
The AP reporter said the dominant mood at the conference was not excitement but gloom.