“Never underestimate the power of a fresh coat of white paint.”
Jeremiah Brent, Designer
It is getting toastier around here (see graphic below). Why? Because humans are emitting carbon dioxide and other gases into the atmosphere. These gases act like a blanket and trap too much of the sun’s radiation close to Earth. Recently, I wrote about the concept of albedo, which is the percentage of the sun’s radiation reflected back by a given surface. Lighter colors reflect more sunlight back, lowering the surface temperature. Given that fact, painting the town white is one simple way to adapt to extreme heat.
Adapting to extreme heat
Cities bear the brunt of heat waves, partly because the dark asphalt and buildings absorb and trap the sun’s radiation. This is why cities are considered urban heat islands. High temperatures cause heat-related illness and death, and also create more demand for energy to keep buildings and people cool. Not good.
There are different adaptive solutions in the works to combat urban heat. One that has gained traction is planting more trees on streets and rooftops. Another idea caught my attention this week: what if, instead of absorbing the heat, roads and rooftops reflected it back? This concept is not new by any means. The beautiful whitewashed buildings in Greece are a great example of this simple strategy to cool things down.
Painting the town white
Cities around the country are starting to switch to reflective materials on roofs and roads. For example, New York City’s program called NYC CoolRoofs is striving to replace roofs with reflective alternatives. A reflective roof can decrease the temperature in a building by up to 9 degrees!
Painting things white helps too, but the whitest paint on the market reflects only 80-90% of sunlight. In an effort to improve upon that, researchers have been working to develop a more reflective paint. A group at Purdue University recently invented the world’s whitest paint. This miraculous substance reflects 98.1% of the sun’s radiation.
An idea worth spreading
Hotspots like Phoenix, LA, and Atlanta are giving reflective paint a try. Researchers in Phoenix found the cool pavement roads were up to 12 degrees cooler! What if all cities in warm climates took this approach? The Purdue researchers estimate that covering just 1% of the Earth’s surface with this ultra-reflective paint would be enough to offset the effects of climate change! This seems like an idea worth spreading.
Let’s do something about climate change. Learn about it. Think about it. Talk about it.