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.

---

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

---

Etymology

Origin of heat island

First recorded in 1960–65

Example Sentences

People living in cities are more at risk from heatwaves than those in rural areas due to the urban heat island effect when heat is trapped by tall buildings, absorbed by tarmac and concrete and released by heating and air conditioning.

From BBC

In a statement, the WMO added: "The effect of heat on human health is more pronounced in cities as a result of the urban heat island effect. This is where urban environments are significantly warmer than surrounding rural areas, especially during hot periods, due to an abundance of paved surfaces, buildings, vehicles, and heat sources."

From BBC

That is because of something called the urban heat island effect.

From BBC

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

In cities, the trend is compounded by the fact that the built environment absorbs and retains more heat than the rural area around it, a phenomenon known as the urban heat island effect.

From Los Angeles Times