What does the urban heat island effect refer to?

The urban heat island effect refers to the phenomenon where urban areas experience higher temperatures compared to their surrounding rural areas, primarily due to human activities. This occurs because cities, with their extensive concrete surfaces, asphalt roads, and buildings, absorb and retain heat more than natural landscapes like forests and fields, which can cool more effectively through vegetation and soil.

This effect is intensified by factors such as reduced vegetation, waste heat from vehicles and buildings, and changes in land use that replace natural landscapes with impervious surfaces. Urban areas, therefore, can be significantly warmer—sometimes by several degrees—particularly during the night when heat retained by buildings and roads is slowly released into the atmosphere. In contrast, rural areas, which often have more vegetation and open spaces, benefit from cooler temperatures.

Understanding this effect is essential for urban planning and public health, as it highlights the importance of integrating green spaces and sustainable practices in cities to mitigate temperature increases and promote more comfortable urban living conditions.