Urban Heat Island

A built-up area that is warmer than the surrounding rural land due to its accumulation of heat. The consumption of energy by buildings and its 'waste' transfer to the environment, as well as heat generated by traffic, population size, the absorption, retention and conduction of heat from roads, pavings and buildings, all contribute to an increase in temperatures in the contained local environment, essentially creating an island of raised heat levels when compared with the surrounding land.

The urban heat island effect can result in significant differences of temperatures arising between urban and adjacent rural areas. One extensive study has shown that temperature differentials of <3°C to 10°C can exist between large urban areas and cities when compared to rural areas in the same localities. (Source: Sangiorgio, V., Fiorito, F. & Santamouris, M. Development of a holistic urban heat island evaluation methodology. Sci Rep 10, 17913 (2020). https://doi.org/10.1038/s41598-020-75018-4)