- News Home
17 April 2014 12:48 pm ,
Vol. 344 ,
Officials last week revealed that the U.S. contribution to ITER could cost $3.9 billion by 2034—roughly four times the...
An experimental hepatitis B drug that looked safe in animal trials tragically killed five of 15 patients in 1993. Now,...
Using the two high-quality genomes that exist for Neandertals and Denisovans, researchers find clues to gene activity...
A new report from the Intergovernmental Panel on Climate Change (IPCC) concludes that humanity has done little to slow...
Astronomers have discovered an Earth-sized planet in the habitable zone of a red dwarf—a star cooler than the sun—500...
Three years ago, Jennifer Francis of Rutgers University proposed that a warming Arctic was altering the behavior of the...
- 17 April 2014 12:48 pm , Vol. 344 , #6181
- About Us
ScienceShot: Bright Roofs, Cool World
12 April 2012 7:01 pm
Making urban roofs and pavements more reflective could cool Earth's climate slightly but measurably at little or no cost, researchers say. Altogether, urban and suburban areas between the latitudes of 45°N and 45°S—a swath that stretches from near Minneapolis, Minnesota, to south-central Chile—cover about 2 million square kilometers, an area slightly larger than Mexico. Because roofs and pavements account for more than 60% of urban surfaces (see image), using lighter-colored roofing materials (concrete versus asphalt, for example) could boost average albedo, or reflectivity, enough to drop global average temperature by as much as 0.07°C, the researchers report online today in Environmental Research Letters. Achieving the same amount of cooling by slashing carbon dioxide emissions would require taking every automobile on the planet off the road for about 50 years, the researchers estimate. Although brightening all of the roofs and pavements in every urban and suburban area worldwide sounds like a Herculean task, it could be done rather easily and relatively quickly with little added expense: Roofs are typically replaced or resurfaced every 20 to 30 years, and streets and roads are repaved every 10 years or so, with brighter alternatives often costing little or no more than the materials now in place, the researchers claim.
See more ScienceShots.