As the earth heats up, cities made hot by concrete are getting even hotter. The City of Los Angeles has declared war on rising temperatures. But the city still has a long ways to go.
This story was made possible with support from the Center for Health Journalism at the University of Southern California.
Photo: Los Angeles city workers spread "cool pavement" material that, once dried, immediately cools the ground 15-20 degrees. (Molly Peterson)