Can the Color of your Roof Impact Climate Change?
White roofs might not be in vogue but apparently they can positively impact climate change.
The cooling effect of white roofs is based on a simple principle of physics. The color “white” reflects sunlight, rather than absorbing it. As such, it also reflects the sun’s heat rather than trapping it. It’s the reason why wearing white clothes keep you cooler in warm climates or in the summer months. If the rooftops of houses and buildings in tropical cities were painted white, then they could potentially reflect enough sunlight back to space to offset huge amounts of carbon dioxide, perhaps more than one year’s worth of global carbon emissions. Hashem Akbari of the Lawrence Berkeley National Laboratory, published a paper last year, in the journal Climatic Change, estimating the “remarkable global cooling potentials” of white roofs in hot cities. According to Akbari, white roofing just “one per cent of the land area of the globe” would reflect enough sunlight to offset the “equivalent to all the world’s cars.” It would also improve smog and air quality (and the associated health care costs), and save $30 billion in energy every year.
So, if you live in a particularly warm climate, and are looking for some handy work around the house, you might consider getting to work with that can of paint.