Indian Cities Are Becoming Urban Heat Islands

This June, about two-thirds of India experienced heat-wave conditions. Indian cities witnessed unusually high temperatures, which caused a spike in heat-related deaths. Although India is no stranger to heat waves, in recent years they have become more frequent, more intense, and of longer duration. This is partly because of the urban heat island effect.

An urban heat island is an area that is substantially warmer than its suburban and rural surroundings. This warming effect depends on various factors—a city’s weather conditions, its geophysical characteristics, and the heat from its buildings, vehicles, and inhabitants. The effect is more severe at night than in the daytime, and intensifies during heat waves. It can operate on different scales: It might occur around a single building, in a neighborhood, or citywide.