heat island

American  

[heet ahy-luhnd] / ˈhit ˌaɪ lənd /

noun

1. an urban area having a higher average temperature than its rural surroundings owing to the greater absorption, retention, and generation of heat by its buildings, pavements, and human activities.

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heat-island British  

noun

1. meteorol the mass of air over a large city, characteristically having a slightly higher average temperature than that of the surrounding air

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Etymology

Origin of heat island

First recorded in 1960–65

Example Sentences

Dehydration and heat stroke can occur when temperatures rise, and urban heat island effects can also help to trap pollution leading to poor air quality.

From BBC • Jun. 28, 2025

Trees also help counteract the urban heat island effect, by which concrete, brick, asphalt and other hard surfaces absorb and reflect heat, increasing local temperatures by as much as 7 degrees.

From Los Angeles Times • Sep. 9, 2024

Ruese also suggested that local leaders improve urban infrastructure so that it reduces heat, and in particular the urban heat island effect.

From Salon • Apr. 15, 2024

"And in addition, you'll have this positive impact on the metropolitan-scale heat island effect."

From Science Daily • Feb. 12, 2024

Seattle has the fourth highest average urban heat island index per capita in the nation, according to Climate Central, and getting hotter with each new building project that paves former green space.

From Seattle Times • Jan. 18, 2024