Cool Your City
Urban areas have more buildings, roads, parking lots and sidewalks than rural areas. These hard surfaces trap heat, raising temperatures in cities by as much as five degrees Fahrenheit. Higher temperatures in cities – known as “heat islands” – can increase the amount of energy used for air conditioning, increase air pollution levels and raise the risk for heat-related illnesses. Hot pavement can also heat up rain water runoff as it passes over – when this warmer water reaches our streams and rivers, it can shock fish and other animals that depend on specific water temperatures to survive.
Viewer Tip: An easy way to help minimize summer heat islands is to plant trees and shrubs around your property. Trees help cool urban climates through shading and evapotranspiration (the process of evaporation and water loss through different parts of a plant). The roots of trees and shrubs also absorb rain water runoff, helping to slow the flow of storm water into our rivers and streams.
For more information on using trees and vegetation in urban landscapes, visit http://www.epa.gov/hiri/resources/pdf/TreesandVegCompendium.pdf
Season: Summer
(Source: U.S. Environmental Protection Agency, http://www.epa.gov/hiri/resources/pdf/TreesandVegCompendium.pdf; NASA. “Coastal Cities Turn Up the Heat on Rainfall.” http://www.nasa.gov/centers/goddard/news/topstory/2003/0523urbanrainfall.html)