基于卫星探测资料的珠江三角洲城市群对降水影响的观测研究

Urbanization Effects on Precipitation over the Pearl River Delta Based on Satellite Data

利用卫星观测TRMM降水以及QuikSCAT风场资料,对珠江三角洲地区及临近区域降水的分布特征进行了探讨,结果表明:(1)同一纬度相比,珠江三角洲城市群所处的区域降水明显多于其周边地区,表明了城市化可能会使所处区域的降水增加;(2)珠江三角洲城市群所处区域降水的增加存在明显的季节变化特征,在前汛期城市所处区域的降水增多较其它季节明显;(3)珠江三角洲城市化对降水的影响与风场的分布密切关联,降水增多的区域通常位于城市群所在之处及其下风方向的邻近地区;(4)珠江三角洲城市化使城市群所处区域的降水时次减少,而降水强度则加强;(5)珠江三角洲城市群的天气、气候效应只对对流性降水产生影响,而层状降水的分布则与城市群的位置没有明显关联。

The urbanization effects on precipitation over the Pearl River Delta area based on TRMM and QuikSCAT data are studied. It is found that： 1） The Pearl River Delta area is a rainfall centre where there is more precipitation than its surrounding area. It is suggested that the urbanization may result in the increase in precipitation over the Pearl River Delta area. 2） The increase in precipitation over the Pearl River Delta area exhibits significant seasonal variabilities. The urbanization-induced precipitation is most remarkable during the first rainy season over South China. 3） The urbanization-induced precipitation is closely related to the wind field. The rainfall centre is located over the leeward area of the city group. 4） The urbanization leads to the strengthening in the intensity of precipitation and the reduction in the rainfall frequency over the Pearl River Delta area. 5） Urbanization seems to affect significantly the convection rainfall rather than the stratiform rainfall.