基于地基微波辐射计的大气液态水及水汽特征分析  

Analysis of the Characteristic of Liquid Water and Water Vapor Detected by Ground-based Microwave Radiometer

作　　者：张文刚[1] 徐桂荣[1] 万蓉[1] 贺文煌 冯光柳[1] 

机构地区：[1]中国气象局武汉暴雨研究所暴雨监测预警湖北省重点实验室,武汉430205 [2]湖北省咸宁市气象局,咸宁437100

出　　处：《暴雨灾害》2015年第4期367-374,共8页Torrential Rain and Disasters

基　　金：国家高技术研究发展计划(863)项目(2012AA120902);湖北省气象局年轻科技人员专项(2014Q03);湖北省气象局科技发展基金面上项目(2014Y06)

摘　　要：大气液态水及水汽的探测对研究灾害性天气具有重要作用,地基微波辐射计可同时获取高时空分辨力的液态水及水汽资料。利用湖北省内三个测站的微波辐射计资料,分析了三站液态水及水汽的时空分布及变化特征。对比武汉站微波辐射计与探空得到的大气可降水量(PWV,precipitable water vapor)发现,两者偏差较小且相关性较好。水汽密度(VD,vapor density)整体随高度递减,2 km以下部分高度的VD在降水时要小于阴天时。液态水含量(LWC,liquid water content)随高度先增后减,降水时其峰值高度明显高于阴天时。降水时,PWV的日变化呈现"一谷一峰"的特征,液态水总量(ILW,integrated liquid water)在白天先增后减,在午后出现峰值,在夜间变化波动较大。受地形影响,荆州液态水总量明显低于武汉、咸宁,咸宁ILW在秋冬季明显高于荆州、武汉。降水发生时,水汽主要在2 km以下积聚,之后被抬升至4 km左右高度凝结并降落。The liquid water and water vapor are important to the study of disastrous weather. High temporal and spatial resolution data of liquid water and water vapor can be obtained by ground-based microwave radiometer. Using the microwave radiometer data in 3 stations of Hubei, the temporal and spatial variations of water vapor and liquid water content retrieved by microwave radiometer are analyzed. Precipitable water vapor（PWV） obtained by microwave radiometer is firstly compared with the radiosonde observation, and the result shows that there is a good correlation between them with relatively small bias. In general, the vapor density（VD） decreases with height, and the vapor density below2 km in rainy condition is lower compare with that in cloudy condition. The liquid water content（LWC） firstly increases with height and then decreases, and the peak is larger in rainy condition than in cloudy condition. A clear diurnal variation of PWV is found in the rainy condition,with a character of＂one peak and one valley＂. The integrated liquid water（ILW） is volatile at night and has the peak value after midday. The ILW of Jing Zhou is significantly lower than that of Wu Han and Xian Ning as water vapor is difficult to condense with the influence of terrain.In autumn and winter, the ILW in Xian Ning is higher than that in Jing Zhou and Wu Han. The water vapor accumulates mainly below 2 km and condenses around 4 km height when precipitation.

关 键 词：微波辐射计 水汽 液态水 变化特征 

分 类 号：P41[天文地球—大气科学及气象学]