Another post for you, written by Ben from Big Green Smile. This time he talks about painting your roof…
“Drive smaller cars, install efficient light bulbs, insulate our lofts, plant trees and don’t fly. Most of us are familiar with the dos and don’ts of climate change but here is something new for your arsenal in the fight. Paint your roof white. A little bit ‘out there’ perhaps but this is the vision of Hashem Akbari, a US scientist based at the Lawrence Berkeley National Laboratory in California.
“The Greeks have been doing this to their beautiful villages for centuries of course but Hashem Akbari believes that painting the grey and let’s face it rather dull buildings of our own towns and cities white will have a tangible benefit in curbing global warming. White/light roofs reflect approximately 50% of the sunlight whereas on black/dark surfaces this is just 10-20%.
“Akbari calculates that a mass movement to paint our roofs white could result in 0.03% additional sunlight being bounced off the earth; enough to cancel out a tremendous 44bn tonnes of CO2, which is the projected increase for the next decade.
“With carbon emissions still rising, painting everything white is not the only answer, by Akbari’s own admission. The idea needs mass contribution for it to be effective but compared to other measures it is relatively simple, does not need protracted long negotiations for it to be effective and is relatively cheap.
“Studies in Los Angeles have shown that replacing two thirds of rooftops and road surfaces with reflective surfaces would cool the city by 2-3C. Although the UK does not have the hot climate of California there are benefits to be had anywhere that has need of air conditioning, and that certainly counts London. Akbari would ultimately like to see his idea included in carbon offsetting schemes and has calculated that every 10 square meters of re-painted reflective surface is preventing the release of a ton of carbon dioxide.
“Time to get the painting clothes on then.”