Turning Up the Heat
Did you know that urban heat islands – where pavement and buildings absorb and trap heat, making cities feel warmer than surrounding natural areas – can actually affect Houston’s weather patterns? Scientists have found that urban heat islands cause warm air to rise, and when this air reacts with sea breezes, it creates more frequent, heavier rainfall in the city! As a matter of fact, analysis of Houston’s rain gauge data both before and during urbanization shows increased rainfall as more heat islands formed in the city.
Viewer Tip: Asphalt, tar, and other dark pavement and roof surfaces absorb and hold heat, even after the sun sets. If you are thinking about adding or replacing a walkway at your home, consider using materials that are less likely to absorb heat, such as gravel, grass, or mulch. Not only will these materials stay cool, but they’ll also allow rain water to soak into the ground instead of running off into the street.
Season: Summer
(Sources: NASA. 2003. “Coastal Cities Turn Up the Heat on Rainfall.” http://www.nasa.gov/centers/goddard/news/topstory/2003/0523urbanrainfall.html; US Department of Agriculture)
