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Heat Island EffectContact Us Share
Heat Island Mitigation Strategies
How to Keep Your Cool
Learn about the five strategies to reduce the heat island effect: trees and vegetation, green roofs, cools roofs, cool pavements, and smart growth.
What Communities are Doing to Reduce Heat Islands
Communities are Taking Action!
Find out what state and local entities across the country are doing to reduce the urban heat island effect.
Heat Island Compendium
Learn how you can reduce the urban heat island effect in your community.
A transcript, recording, and slides are now available from the September 12, 2018 webcast Cool Fixes for Hot Cities Part 2: Los Angeles.
Check out our newly sprouted webpage, Using Green Roofs to Reduce Heat Islands!
Heat Island Effect
The term "heat island" describes built up areas that are hotter than nearby rural areas. The annual mean air temperature of a city with 1 million people or more can be 1.8–5.4°F (1–3°C) warmer than its surroundings. In the evening, the difference can be as high as 22°F (12°C). Heat islands can affect communities by increasing summertime peak energy demand, air conditioning costs, air pollution and greenhouse gas emissions, heat-related illness and mortality, and water quality.
Learn About Heat Islands
Reduce the Risks
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