London is surrounded by a green belt
Jonathan Wilson / Alamy Stock Photo
Preserving a “green belt” of countryside around urban areas helps keep cities cool during the hottest times of the year, suggesting that new UK plans to build on currently unoccupied land could affect urban temperatures.
We already know that many cities experience an urban heat island effect, as buildings and other human-made objects retain more heat than rural land. But as warm air rises in a city, it creates a layer of low pressure near the ground, which draws in cooler air from the surrounding countryside.
