http://news.yahoo.com/s/ap/20110403/ap_on_hi_te/eu_the_sunshade_optionI just cut a few interesting bits from the article for those of you who dont want to read the whole thing.
CHICHELEY, England – To the quiet green solitude of an English country estate they retreated, to think the unthinkable.
Scientists of earth, sea and sky, scholars of law, politics and philosophy: In three intense days cloistered behind Chicheley Hall's old brick walls, four dozen thinkers pondered the planet's fate as it grows warmer, weighed the idea of reflecting the sun to cool the atmosphere and debated the question of who would make the decision to interfere with nature to try to save the planet.
The unknown risks of "geoengineering" — in this case, tweaking Earth's climate by dimming the skies — left many uneasy.
Those techniques are necessarily limited in scale, however, and unable to alter planet-wide warming. Only one idea has emerged with that potential.
"By most accounts, the leading contender is
stratospheric aerosol particles," said climatologist John Shepherd of Britain's Southampton University.
Many here worried that someone, some group, some government would decide on its own to conduct large-scale atmospheric experiments, raising global concerns — and resentment if it's the U.S. that acts, since it has done the least among industrial nations to cut greenhouse emissions. They fear some in America might push for going straight to "Plan B," rather than doing the hard work of emissions reductions.
In addition, "one of the challenges is identifying intentions, one of which could be
offensive military use," said Indian development specialist Arunabha Ghosh.
Experts point out, for example, that cloud experimentation or localized solar "dimming" could — intentionally or unintentionally — cause droughts or floods in neighboring areas, arousing suspicions and international disputes.
