Building green belts in the thermal cycle of cities and suburbs can purify the air blowing from suburbs to cities, produce ecological benefits, and play a good role in regulating temperature and increasing air humidity.
Urban heat island circulation is a meteorological term. The urban population is concentrated and the industry is developed. Residents' lives, industrial production and vehicles consume a lot of fossil fuels such as oil and natural gas every day, releasing a lot of waste heat, which leads to the temperature in the city being higher than that in the suburbs, making the city like a warm island, which is called "urban heat island".