上海及周边地区气溶胶对云和降水的影响初探  

Tentative discussion on the impact of aerosol on cloud and precipitation over Shanghai and its surrounding areas

作　　者：彭杰[1,2] 

机构地区：[1]北京师范大学,北京100875 [2]上海气象科学研究所,上海200030

出　　处：《暴雨灾害》2015年第4期324-334,共11页Torrential Rain and Disasters

基　　金：国家重点基础研究发展计划(2013CB955804);公益性行业(气象)科研专项(GYHY210406023);国家自然科学基金项目(41375080;41275021);上海市科委项目(13231201400)

摘　　要：利用2000年4月—2013年9月搭载于Aqua和Terra卫星上的中分辨率成像光谱仪（moderate-resolution imaging spectroradiometer,MODIS）遥感资料,首先分析上海及周边地区气溶胶光学厚度（AOD）的长期统计特性,而后配合地面自动气象站降水资料,分析气溶胶与不同类型云的特征参数和地面降水之间的关系,研究该地区气溶胶与云和降水的相互作用。结果表明：上海及周边地区AOD年均值从2000—2009年和2011—2013年分别呈现增强、减弱趋势,而2010年出现明显低值。随着气溶胶增多,该地区浅薄水云的发生频率减少15.5%~32.4%,而深厚混合云的发生频率增加2.1%~10.0%。气溶胶增多对水云云滴粒子有效半径变化的影响受环境水汽条件影响很大,当水汽条件充分（不足）时,气溶胶增多会导致水云云滴粒子有效半径增加（减弱）。深厚混合云的云顶温度随AOD增加而显著减少。气溶胶较多时,降雨量小于1.0 mm·h-1的较弱降水发生频率减少,而降雨量大于等于1.0 mm·h-1的较强降水发生频率增加,说明气溶胶增多会抑制弱降水发生而加强强降水发生。Based on retrievals from the moderate-resolution imaging spectroradiometer（MODIS） abroad on satellite Aqua and Terra from April 2000 to September 2013 and rainfall records from automatic weather stations, we investigated the long term statistical properties of aerosol optical depth（AOD） over Shanghai and its surrounding areas. Then we analyzed the relationship between AOD and feature parameters for different types of clouds and surface precipitation. Lastly, we studied the interaction between aerosol and cloud and precipitation. Results show that the annual mean AOD has an increase and a decrease trend from 2000 to 2009 and 2011 to 2013, respectively, but a significant decrease in 2010 over Shanghai and its surrounding areas. With the increase of aerosol, the occurrence frequency of shallow liquid clouds reduces by 15.5%-32.4%, while that of deep mixed-phase clouds enhances by 2.1%-10.0%. The effect of the increasing aerosol loading on cloud liquid effective radius strongly depends on the environmental moisture conditions. Increasing aerosol loading tends to enhance（reduce） the liquid effective radius with sufficient（insufficient） moisture. The cloud top temperature of deep mixed-phase clouds decreases significantly with the increase of AOD. When aerosol loading is high, the occurrence frequency of relatively weak precipitation（hourly precipitation of less than 1.0 mm） reduces, while that of relatively strong precipitation（hourly precipitation of more than or equal to 1.0 mm） enhances, which indicates that the increase of aerosol loading will inhibit the occurrence of weak precipitation but strengthen that of strong precipitation.

关 键 词：气溶胶 云 降水 上海 

分 类 号：P426.6[天文地球—大气科学及气象学]