Final answer:
Temperatures over urban and metropolitan cities are generally lower than temperatures in the adjacent rural surroundings due to the urban heat island effect. This is caused by the absorption and retention of heat by buildings, roads, and other surfaces in cities. Lack of vegetation in urban areas also contributes to higher temperatures.
Step-by-step explanation:
Temperatures over urban and metropolitan cities are generally lower than temperatures in the adjacent rural surroundings. This phenomenon is known as the urban heat island effect. Urban areas tend to have more buildings, roads, and other surfaces that absorb heat and radiate it back into the environment. This leads to higher temperatures in cities compared to rural areas.
Furthermore, cities often lack vegetation, which plays a crucial role in cooling the environment through evapotranspiration. Without enough trees and plants, there is less shade and evaporation taking place, resulting in higher temperatures.
For example, during a hot summer day, the pavement in a city can reach temperatures much higher than the surrounding grassy fields or forests. This is caused by the absorption and retention of heat by concrete and asphalt surfaces.