Changes in Urban Landscape Can Cut Smog

According to a pair of studies by the University ofCalifornia's Lawrence Berkeley National Laboratory, doubling the number of mature trees and resurfacing dark-colored roofs and roads with heat-reflecting material in Sacramento County would almost halve

1 minute read

October 10, 2000, 7:00 AM PDT

By California 2000


Funded by the U.S. Environmental Protection Agency, the study used aerial photographs taken with infrared cameras to make temperature maps; the images showed that rooftops and blacktops were the hottest areas in a city, while parks were the coolest. Preliminary releases indicate that on a hot day, the population center of the county is 1 to 2 degrees hotter than less-developed areas. As increased temperatures speed the formation of smog, lowered temperatures would decrease the amount of smog produced. The study calculated that doubling the number of trees along with cooling roof and pavement surfaces would result in a temperature drop of 2 to 3 degrees, and cause a 6 to 8 percent drop in ozone levels.

Thanks to California 2000 Project

Tuesday, October 10, 2000 in The Sacramento Bee

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