Urban heat effect: Why are larger cities warmer than rural communities?

(Photo: WKRN)

NASHVILLE, Tenn. (WKRN) – If you pay attention to local forecasts in Middle Tennessee, you may have noticed the difference in temperature between larger cities like Nashville and smaller more rural communities like Portland or Lawrenceburg.

This is caused by a phenomenon known as urban heat island effect. But what does that mean?

An urban heat island is a metropolitan area that is a lot warmer than surrounding rural areas. As the sun shines down across Middle Tennessee, the temperature will increase across all areas.

Plants, buildings, sidewalks, cars, and even people absorb this solar energy. Some materials, like concrete and steel are more efficient at absorbing and holding this heat energy from the sun.

Have you ever walked across an asphalt parking lot in the middle of summer? You can actually feel the heat coming off the ground.

This causes temperatures in cities to be higher than rural communities. This is known as the urban heat island effect.

Smaller cities have more trees, grass, and soil which has a smaller heat capacity than building materials found in a city.