heat island

Also known as: heat island effect

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Last updated

June 29, 2026

Quick Summary

A heat island is an urban area that is significantly warmer than its surrounding rural environments. This phenomenon occurs because urban structures like buildings and paved surfaces absorb and retain more solar energy than natural landscapes. Additionally, cities have less greenery, which reduces the cooling effect of evaporation and transpiration.

During the day, urban materials store heat and release it at night, keeping cities warmer. In winter, heat generated from buildings, vehicles, and industry further contributes to higher urban temperatures. This temperature difference between urban and rural areas is known as the "urban heat island effect."12

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urban climate
…influence the formation of this “heat island.” During summer, urban masonry and asphalt absorb, store, and reradiate more solar energy per unit area than do the vegetation and soil typical of rural areas. Furthermore, less of this energy can be used for evaporation in urban areas, which characteristically exhibit greater…
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…influence the formation of this “heat island.” During summer, urban masonry and asphalt absorb, store, and reradiate more solar energy per unit area than do the vegetation and soil typical of rural areas. Furthermore, less of this energy can be used for evaporation in urban areas, which characteristically exhibit greater…
Read More