What defines urban heat islands?

Urban heat islands refer to urban areas that experience significantly higher temperatures than their rural surroundings due to various human activities. This phenomenon occurs primarily because built environments, such as roads, buildings, and other infrastructure, absorb and retain heat more than natural landscapes. Surfaces like asphalt and concrete have lower albedo, meaning they reflect less solar energy and instead store it as heat, which ultimately raises the local temperature.

Additionally, factors such as reduced vegetation, which typically provides cooling through shade and evapotranspiration, further contribute to the temperature differences. As urbanization increases, the concentration of buildings and vehicles, along with industrial activities, leads to more heat generation, exacerbating the urban heat island effect. This understanding is crucial when addressing climate change and energy consumption in cities, as it can impact energy demands, air quality, and public health.