According to an environmental report in today's Guardian U.K., Los Angeles may go green by painting its roofs and roads white. The article features U.C. Berkeley scientist Hashem Akbari, whose mission is to reduce “urban heat islands” by painting rooftops, parking lots and roads with reflective paint that would bounce back the sun's light, instead of letting it get absorbed.
Above: Palm Springs bakes.
Photo: Alamy/Guardian UK
Since 2005, California has required flat-topped warehouses to
paint their roofs white. Akbari calculates that by covering the earth's
urban surfaces and roads — which account for 2.4 percent of the
planet's dry land — we could bounce back about .03 of the sun's rays.
That would be enough to noticeably slow the upward temperature climb in an age of global
One objection that has been raised in the past is the desirability of having white-surfaced roads that shimmer and streets
of houses with glaring roofs. Akbari notes, however, that merely moving
from near-black asphalt to gray will increase the reflection of
sunlight and that there are materials that can be used in darker paints
that will reflect more infrared light that is currently being bounced
“Computer simulations of Los Angeles,” the article
notes, “show that resurfacing about two-thirds of roads and rooftops
with reflective surfaces, as well as planting more trees, could cool
the city by 2-3C. That would reduce LA smog as much as a total ban on
cars and lorries, and cooler roofs could also save a fortune in