Paint it white

Akbari is no architect and his grand plan is no conceptual art project. Based at the prestigious Lawrence Berkeley National Laboratory in California, Akbari is a scientist who has come up with a new way to fight global warming. It could be the easiest solution you've never heard of.
His big idea is based on principles as old as the whitewashed villages that scatter the hills of southern Europe and North Africa. Turn enough of the world's black urban landscape white, he says, and it would reflect enough sunlight to delay global warming, and grant us some precious breathing space in the global struggle to control carbon emissions.

Together, roads and roofs are reckoned to cover more than half the available surfaces in urban areas, which have spread over some 2.4% of the Earth's land area. A mass movement to change their colour, Akbari calculates, would increase the amount of sunlight bounced off our planet by 0.03%. And, he says, that would cool the Earth enough to cancel out the warming caused by 44bn tonnes of CO2 pollution. If you think that sounds like a lot, then you're right. It would wipe out the expected rise in global emissions over the next decade. It won't solve the problem of climate change, Akbari says, but could be a simple and effective weapon to delay its impact - just so long as people start doing it in earnest. "Roofs are going to have to be changed one by one and to make that effort at a very local level, we need to have an organisation in place to make it happen," he says. Groups in several US cities, including Houston, Chicago and Salt Lake City, are on board with his plan, and he is talking to others.

full article here:
http://www.guardian.co.uk/environment/2009/jan/16/white-paint-carbon-emissions-climate