White roofs make cities cooler

Posted by Laura Grant on September 17, 2008
Posted in Green News

Researchers at the Lawrence Berkeley National Laboratory in California have calculated that 1.5 years of man-made carbon emissions could be offset simply by making roofs and roads in the world’s cities white, reports Science Daily News. The roofs would reflect some of the sun’s radiation back to space (albedo effect) and the inside of houses would be cooler, needing less air conditioning, and thus saving energy – the bulk of which is generated by burning fossil fuels.

The researchers estimate that, globally, roofs account for 25 percent of the surface of most cities, and roads accounts for about 35 percent. If all of these were replaced with reflective material – such as lighter-coloured concrete or white or more reflective paint – in 100 major urban areas, it would offset 44 gigatons of greenhouse gases, reports the LA Times. This is reportedly a bigger saving than you’d get from halting the deforestation of tropical forests. And it’s more than the 28 gigatons per year or so that the world currently emits from fossil fuels, ScienceNow Daily News reports.

Lighter surfaces would also help to lower the temperature in cities, making them cooler places to live.

For more information: Heat Island Group, Global Cooling: Increasing worldwide urban albedos to offset CO2


One Response to “White roofs make cities cooler”

  1. Alfred Hayter
    February 15th, 2009 @ 7:04 pm

    So simple. Why is legislation not passed requiring all new roofs to be white or of reflective material, and all repainting of roofs be white? It would at least spare us the faux tiled Tuscan horrors. And can tar be made white – or whiter? I got crapped on when I mentioned this to a friend: “There’d be so much glare, you wouldn’t be able to see where you’re going.” Wear shades?

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