Los Angeles is covering the blacktop asphalt of its streets with a more reflective “cool pavement” white treatment to reduce the urban warming heat island effect. What’s that? Are there island in Los Angeles? No no, the urban heat island effect means that the temperature in cities are higher than in the surrounding rural areas.
This island of heat is caused by a lack of trees casting shadow and a large amount of black asphalt that can absorb 90% of the sunlight and store this warmth.
LA’s mayor says that he expects to lower the temperature by three degrees in the next 20 years. This will be achieved by painting the streets with a white coating able to decrease the street temperature by 15 degrees. The process behind this is really simple, wear a black shirt in the sun and you will sweat, wear a white shirt in the sun and you will be nice and cool, because the light gets reflected instead of absorbed.
Installing ”cool roofs” on buildings, ”cool seal” coatings on the streets and more trees around the city might turn Los Angeles into a white dot visible from space.