'Cool' roofs could combat climate change

BERKELEY, Calif., July 20 (UPI) -- Light-colored rooftops and roads could significantly cut emissions and combat global climate change by cooling cities and the world, researchers say.

Scientists at Lawrence Berkeley National Laboratory in California say cool roofs and cool pavements in cities around the world could cancel the heating effect of up to two years of worldwide carbon dioxide emissions, ScienceDaily.com reported Tuesday.

U.S. Energy Secretary Steven Chu has announced efforts at the Department of Energy to implement cool roof technologies on department facilities and on buildings across the federal government, ScienceDaily said.

"Cool roofs are one of the quickest and lowest cost ways we can reduce our global carbon emissions and begin the hard work of slowing climate change," said Chu.

Berkeley Lab researchers found that increasing the reflectivity of roof and pavement materials in cities with a population greater than 1 million would achieve a one-time offset of CO2 emissions double the worldwide CO2 emissions levels in 2006.

"These offsets help delay warming that would otherwise take place if actual CO2 emissions are not reduced," Berkeley Lab scientist Surabi Menon said.

"Cool roofs have worked for thousands of years in the Mediterranean and Middle Eastern cities, where demand for air conditioning is low," Menon's colleague Hashem Akbari said. "If you have a cool roof on your house, that will reduce your energy use from air conditioning and it's a gift that keeps on giving for many, many years, for the life of the roof."