2009年陕西春季层状云增雨卫星观测分析  

Satellite Observation on Rainfall Enhancement in Stratiform Clouds over Shaanxi Province in Spring 2009

作　　者：刘贵华[1] 余兴[1] 贾玲[2] 岳治国[2] 戴进[1] 

机构地区：[1]陕西省气象科学研究所,陕西西安710014 [2]陕西省人工影响天气中心,陕西西安710014

出　　处：《干旱区研究》2011年第4期699-704,共6页Arid Zone Research

基　　金：国家自然科学基金(40975087);科技部公益项目(2005DIB3J099);陕西省科技攻关项目(2009K11-05)共同资助

摘　　要：通过对2009年2月7～8日陕西层状云降水过程的分析,用MODIS极轨卫星资料反演云系微物理特征。结果表明:①2月7日白天云顶温度-10℃,云滴有效半径(Re)为10μm左右,云体较厚,含有丰富过冷水,冰晶或大滴不足;②夜间在有高云参与的情况下,产生了较好的降水;③持续稳定的中低层状云系存在较好的增雨作业机会。用FY2C静止卫星跟踪云系的演变发现:云系维持时间达30 h,7日白天到夜间云层增厚,Re稳定,降水少,这类云的自然降水过程较弱,具有较好的增雨作业潜力。综合分析得到适宜过冷层状云人工增雨作业条件的初步卫星判据为:云厚达2 km以上,云顶温度-10～-20℃,云顶Re小于15μm。为卫星在人工增雨的条件选择上提供了新的应用途径。Because of the advantages of cloud detection with satellite,the cloud structure and precipitation formation process can be analyzed from different configurations of cloud thickness,particle size and cloud top properties by the retrieval and multi-spectral analysis of satellite data,and consequently the potential of rainfall enhancement can be investigated based on the assumptions of rainfall enhancement and the available research achievements.A new applicable tool will be provided for satellite detection of the conditions of precipitation enhancement.A precipitation process of stratiform clouds from 7 to 8 February,2009 was selected to analyze rainfall enhancement with MODIS polar orbiting satellite data.The retrieval microphysical characteristics of the clouds are as follows：（1） The cloud top temperature was about-10 ℃,the effective radius（Re） of cloud top was around 10 μm,the cloud body was thick,and the clouds were rich in supercooled water but lack of ice crystals or large drops at daytime of 7 February;（2） Rainfall occurred under the participation of high clouds;（3） There was a good opportunity for rainfall enhancement because of the existence of sustained and stable low-level stratiform clouds.Cloud tracking with FY2C geostationary satellite revealed that the cloud system lasted for 30 hours,in which clouds grew thick gradually with stable Re and less rainfall from the daytime to the night of 7 February.Although precipitation process of such clouds was weak,there was a good potential for precipitation enhancement operation.After the comprehensive analysis,the suitable criteria for detecting rainfall enhancement of supercooled stratiform clouds with satellite can be summarized as： the thickness of clouds is about 2 km,and cloud top temperature ranges from-10 ℃ to-20 ℃ with Re less than 15 μm.

关 键 词：卫星反演 层状云 人工增雨条件 过冷云 卫星判据 陕西 

分 类 号：P481[天文地球—大气科学及气象学]