Talk of manipulating Earth's climate via the boston globe

"We found that if you blocked 20 percent of the sunlight over the Arctic Ocean, it would be enough to restore sea ice," he said. "That would be blocking 1/300th of the entire sunlight hitting the Earth, but focusing it on the Arctic would prevent the ice from melting."

"We really have only a limited understanding in the world system, and how we impact it now, and how the Earth responds to the greenhouse gases now," he said. "The notion we would then intentionally do something to correct that, to change the balance of the Earth by some specific action, well, I'd be very cautious about that."