摘要
应用观测资料分析和数值模拟的方法来研究城市中水体的微气候效应,结果表明,城市中的水体对其周边的小气候有着明显的调节作用。城市中商业区温度最高、湿度最小;交通区次之;水体附近温度最低、湿度最大,平均湿度比商业区高出约10%。水体区的月平均温度日较差比其他功能区明显大。水体区的月平均温度比其他功能区低0.37-1.15℃。水体对环境的影响主要发生在上风岸2 km以内和下风岸9 km以内,以2.5 km以内最为明显。水体的面积和布局是影响小气候效应的重要因素。水体面积越大对环境影响越大,单块的小于0.25 km2的水体对环境的影响不明显,但是多块、密集分布的小面积水体会对环境的降温增湿效果更显著。在本文个例中,与其他湖泊邻近的面积为1.25 km2的水体,可以使2.5 km之内温差达到0.2-1.0℃,水汽比湿增加0.1-0.7 g/kg。相对孤立的面积为2 km2的水体,可以使1.0 km范围内降温幅度0.6℃,水汽比湿增加0.1-0.4 g/kg。水体可以使地面风速增加,一般能使风速增加0.1-0.2 m/s。
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 kin, especially within 2. 5 kin. The size and the distribution of the water body contribute greatly to microclimate effects. Single water body less than 0. 25 krn2 almost has no iniluence on the environment, while multiple, dense water body can obviously affect the microclimate. The water body with area of 1.25 km2 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 km2 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 kin. The water body also has effects on wind. The wind speed near the water body may increase by 0. 1 - 0. 2 m/s.
出处
《大气科学》
CSCD
北大核心
2008年第3期552-560,共9页
Chinese Journal of Atmospheric Sciences
基金
国家自然科学基金资助项目40652001、40505002
北京市自然科学基金项目8051002
中国科学院大气物理研究所中层大气与全球环境探测实验室资助
关键词
城市中的水体
微气候效应
数值模式
water body in a city, microclimate effect, numerical model
