Heat islands are urbanized areas that experience higher temperatures than outlying areas. Structures such as buildings, roads, and other infrastructure absorb and re-emit the sun’s heat more than natural landscapes such as forests and water bodies. Urban areas, where these structures are highly concentrated and greenery is limited, become “islands” of higher temperatures relative to outlying areas. Daytime temperatures in urban areas are about 1–7°F higher than temperatures in outlying areas and nighttime temperatures are about 2–5°F higher. Learn more about the impacts and how to measure heat islands.

• What are Heat Islands?

  

  Learn about heat island causes, characteristics, impacts, and solutions to reduce them.

  Explore the Causes and Impacts

• Measuring Heat Islands

  

  Find key considerations for assessing local heat island effects.

  Discover Measurement Frameworks