Even painting just 20 percent of roofs and pavements in a city could reduce air temperatures by 0.8C. Picture: Wikimedia Commons

The effects of global warming could be reduced by painting our roofs and pavements white, a study suggests.

Replacing dark-coloured surfaces in towns and cities could lower temperatures by as much as 2C, scientists claim.

Even painting just 20 percent of roofs and pavements in a city could reduce air temperatures by 0.8C.

Researchers from Sussex University said urban areas will bear the brunt of global warming as they are much hotter than surrounding countryside.

This is because dark, hard surfaces such as tarmac soak up heat, creating "urban heat islands". However, white and light-coloured surfaces reflect heat and light away, meaning less is absorbed, they wrote in journal Nature Climate Change.

Study co-author Richard Tol, Professor of Economics at the university, said: "London is about 4 degrees hotter than the surrounding countryside.

"If you painted all the roofs white, and carried out other measures, it could reduce the temperature by 2 degrees." Lighter building materials and more plants would also help.