Nature Climate Change study suggests that greater use of white roofs could combat the worst excesses of global warming
Imagine you have driven from St. Bees to Carlisle. You couldn’t be bothered with the train, so you chose to drive the distance, in spite of its marginal difference in journey time. One thing you would have noticed is that Carlisle is a little warmer due to a phenomena known as urban heat islands. Dark roofs and tarmac roads have been hailed as a culprit. According to a peer-reviewed letter in Nature Climate Change magazine, white roofs have been hailed as an answer to reversing these issues.
In the letter, it is stated that white roofs and lightly coloured roofs absorb less heat than darker roofs. For example, slate roofs or dark metal roofs. Francisco Estrada, W. J. Wouter Botzen, and Richard S. J. Tol, co-signatories to the letter have recommended that light coloured or white roofs should be used in cities and major towns.
Why cities and major towns? Urban heat islands, caused by built-up areas absorb more energy, and increase temperatures. In the study, it was said that a rural area, a short distance from London, was 4°C cooler than the capital. Opting for white roofs would bridge these gaps, cutting the temperatures of Carlisle, Manchester, Glasgow, or countless other cities by 2°C.
Around the world, cities cover 1% of the Earth’s surface and over half the world’s population. They produce 80% of the Gross World Product and consume 78% of the world’s energy. Richard S. J. Tol from Sussex University said: “People have talked about global climate change, but there is local climate change as well. Cities are warmer than the countryside surrounding it, so it exacerbates the negative effects of climate change.”
D and A Plumbing and Electrical Contractors, 31 May 2017.