Analysis of Microclimate Effects of Water Body in a City

Abstract

The microclimate effects of water body are studied by means of automatic meteorological observing station data analysis and numerical simulation.The results show that: The water body in a city contributes greatly to microclimate effects.Business areas have the maximum temperature and the minimum humidity,traffic areas take second place,and water body areas have the lowest temperature and the maximum humidity.The monthly-mean daily range of temperature in water body areas is obviously larger than that in other areas.Mean temperature in water body areas is 0.37-1.15℃ lower than that in other areas.The water body's microclimate effects are most obvious at the upwind shore within 2 km and at the lee shore within 9 km,especially within 2.5 km.The size and the distribution of the water body contribute greatly to microclimate effects.Single water body less than 0.25 km~(2) almost has no influence on the environment,while multiple,dense water body can obviously affect the microclimate.The water body with area of 1.25 km~(2) which abuts on other water bodies can make the temperature decrease by 0.2-1.0℃ and make the water vapour content increase by 0.1-0.4 g/kg within 2.5 km.An isolated water body with area of 2 km~(2) can lead to 0.6℃ decrease in the temperature and 0.1-0.4 g/kg increase in the water vapour content within 1.0 km.The water body also has effects on wind.The wind speed near the water body may increase by 0.1-(0.2 m/s.)