Cancun climate change summit: UN consider putting mirrors in space - Telegraph

Addressing the opening conference, Dr Pachauri said if mankind continues to pump out greenhouse gases at the current rate the world could experience catastrophic warming within the next fifty years.

He said the threat is so great that the fifth assessment report (AR5), due to be presented to the UN in 2014, will look at "geo-engineering options".
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Options include putting mirrors in space to reflect sunlight or covering Greenland in a massive blanket so it does not melt.

Sprinkling iron filings in the ocean "fertilises" algae so that it sucks up CO2 and "seeding clouds" means that less sunlight can get in.

Other options include artificial "trees" that suck carbon dioxide out of the air, painting roofs white to reflect sunlight and man-made volcanoes that spray sulphate particles high in the atmosphere to scatter the sun's rays back into space.

Scientists Considered Pouring Soot Over the Arctic in the 1970s to Help Melt the Ice - In Order to Prevent Another Ice Age → Washington's Blog

On April 28, 1975, Newsweek wrote an article stating:

Climatologists are pessimistic that political leaders will take any positive action to compensate for the climatic change, or even to allay its effects. They concede that some of the more spectacular solutions proposed, such as melting the Arctic ice cap by covering it with black soot or diverting arctic rivers, might create problems far greater than those they solve. But the scientists see few signs that government leaders anywhere are even prepared to take the simple measures of stockpiling food or of introducing the variables of climatic uncertainty into economic projections of future food supplies. The longer the planners delay, the more difficult will they find it to cope with climatic change once the results become grim reality.