Roads are normally paved with darker shades of grey – the color of concrete and asphalt. But if you happen to pass by Los Angeles in California and see white or light grey ones, do not be surprised for that color has its purpose.
Initiated by Los Angeles Mayor Eric Garcetti, painting the Los Angeles roads as white aims to help cool the city.
A reflective white coating called CoolSeal was originally developed by engineers for military air bases to keep spy planes cool while they rest on the tarmac. But it was discovered that the same material could keep streets and parking lots a lot cooler than usual.
“We found that on average the area covered in CoolSeal is 10 degrees cooler than black asphalt on the same parking lot,” said Greg Spotts, the assistant director of the Bureau of Street Services for San Fernando Valley, one of the hottest spots in Greater LA. The coating was first tested in 2015 in this part of the town.
Photo via LA Street Services
A city like Los Angeles is prone to a phenomenon called urban heat island effect. This means that the shortage of trees, which provide shade, and the black pavement, which absorbs heat from the sun, have a tremendous effect in the overall temperature of the area.
The CoolSeal is quite an investment. For $40,000 per mile and lasting for seven years, it is hoped to result in cooler streets which in turn could cool homes, keeping energy costs and health risks low.
The long-term goal of the city mayor is to reduce the city’s average temperature by 3 degrees Fahrenheit over the next 20 years.
Photos via LA Street Services
While painting the roads white is its primary initiative to keep the city warm, Los Angeles urges its residents to plant more trees and apply white paint to rooftops for those who do not have solar panels.
Mayor Garcetti realizes the need for this kind of initiatives. “This is an urgent challenge, and it’s much bigger than one person,” he said in a statement.
“Climate change is a fact of life that people in Los Angeles and cities around the world live with every day,” he added.