Urban Heat Islands

Cities are often several degrees warmer than the surrounding countryside. This phenomenon, known as the urban heat island effect, has several causes. Concrete and asphalt absorb heat during the day and release it slowly at night. Air conditioners, vehicles and factories add even more heat to the environment. The lack of trees means there is less shade and less natural cooling. During heatwaves, these higher temperatures can pose serious health risks. Planners are responding by planting trees and creating green roofs. Some cities are also painting surfaces in light colours to reflect sunlight. Such measures can make urban life more comfortable and sustainable.