08 Mar 2012:
New York Roof Study Shows
Drastic Cooling with White Surfaces
A New York City roof covered in a white synthetic membrane was on average 43 degrees F cooler than surrounding black tar and asphalt roofs
during times of peak heat last summer, according to a study by scientists from Columbia University and NASA. On the hottest day of the summer — July 22, 2011,
when the city set a record for electricity usage during a heat wave — the dark surfaces of some New York City roofs reached 170 degrees F, while temperatures on the white test roof peaked at less than 130 degrees F. The city’s CoolRoofs initiative
is working to install “living roofs” with plants and to convert many tar and asphalt roofs to a white color using membranes or white paint. The goal, the city says, is to help reduce the urban “heat island” effect, which can boost temperatures by 5 to 7 degrees F, especially at night. Lowering the heat island effect would reduce demand for air conditioning and cut illnesses and deaths during heat waves. Converting roofs to white is cheaper than planting “living roofs,” and research showed said that the white membrane roof performed well over numerous years of the study. “Bright is the new black,” said Stuart Gaffin, a Columbia research scientist and lead author of the study, published in Environmental Research Letters.
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Tribal people and ranchers join together to stop a project that would haul coal across their Montana land. Watch the video.
is now available for mobile devices at e360.yale.edu/mobile
An aerial view of why Europe’s per capita carbon emissions are less than 50 percent of those in the U.S. View the photos.
Ugandan scientists monitor the impact of climate change on one of Africa’s most diverse forests and its extraordinary wildlife. Learn more.
video series looks at the staggering amount of food wasted in the U.S. – a problem with major human and environmental costs. Watch the video.
video goes onto the front lines with Colorado firefighters confronting deadly blazes fueled by a hotter, drier climate. Watch the video.
A three-part series Tainted Harvest
looks at the soil pollution crisis in China, the threat it poses to the food supply, and the complexity of any cleanup. Read the series.