People living in the city will have such an experience, that is, the temperature of the city is higher than that of the suburbs. So why is this? Interest Knowledge Network tells you why the temperature in the city is higher than that in the suburbs.

The results of recent decades have shown that the temperature in the city is much higher than that in the suburbs. This is what people often call the “urban heat island effect”. For example, Shanghai and New York have an average annual temperature of 1.1 degrees Celsius higher than that of the suburbs, Berlin is 1.0 degrees Celsius, Philadelphia and the suburbs are 0.8 degrees Celsius, Moscow, Paris, and Los Angeles are 0.7 degrees Celsius higher, and Washington is 0.6 degrees Celsius.

Why is the temperature in the city higher than the suburbs? The main factors affecting the city temperature are the following: First, the factory is dense, the industrial heat source and energy utilization rate are low, and the large amount of heat discharged from automobiles and various motor vehicles; the second important reason is the bricks in the city. Stone, cement, and asphalt roads reflect less solar radiation, so they absorb more heat during the day. Third, because of the good drainage facilities in the city, the rainwater after rain is quickly lost from the artificial pipeline, thus losing evaporation. The amount of heat in the water is very small; the fourth is that the density of urban buildings is too large, the ventilation is not smooth, and the heat is difficult to escape.

In addition, the smoke that often appears over the city plays a role in heat preservation at night. Therefore, the urban heat island effect at night is much more obvious than the white day. On the rest day, the factory does not start construction, and the amount of heat emitted is small. The urban heat island effect is weaker than usual.