藏东南墨脱地区云中过冷水的毫米波雷达观测  

Retrieval of Supercooled Liquid Water in Clouds over the Medog Region of Southeastern Tibet Using Millimeter-wave Radar Measurements

作　　者：周港又 王改利[2] 郑佳锋[1] 任涛 张静怡 谢冰洁 ZHOU Gang-you;WANG Gai-li;ZHENG Jia-feng;REN Tao;ZHANG Jing-yi;XIE Bing-jie(School of Atmospheric Sciences,Chengdu University of Information Technology,Chengdu 610225,China;State Key Laboratory of Severe Weather,Chinese Academy of Meteorological Sciences,Beijing 100081,China;Henan Provincial Atmospheric Exploration Data Center,Zhengzhou 450003,China)

机构地区：[1]成都信息工程大学大气科学学院,成都610225 [2]中国气象科学研究院灾害天气国家重点实验室,北京100081 [3]河南省气象探测数据中心,郑州450003

出　　处：《科学技术与工程》2023年第31期13243-13253,共11页Science Technology and Engineering

基　　金：第二次青藏高原综合科学考察研究项目(2009QZKK0105);中国气象科学研究院科技发展基金(2023KJ041);国家自然科学基金(41775036)。

摘　　要：云中过冷水识别对于人工影响天气及预防飞机积冰具有重要意义,但过冷水的识别一直是气象探测中的难点,毫米波雷达是连续探测云结构和物理特征的有效工具。利用布设在藏东南水汽通道入口处墨脱地区的Ka波段毫米波云雷达基数据,结合微波辐射计温度资料,采用基于模糊逻辑法、阈值法进行过冷水识别,识别出的粒子相态包含冰、雪、过冷水及混合态。并利用同址的微波辐射计的液态水路径(liquid water paths,LWP)对墨脱云雷达观测的两个层积云过程的过冷水识别效果进行了分析和初步验证。结果表明:模糊逻辑法和阈值法识别的过冷水基本合理,但模糊逻辑法可以识别更多的过冷水,从定量分析来看,模糊逻辑法相对于阈值法识别的LWP更接近于微波辐射计。藏东南墨脱地区层积云中过冷水的微物理参数与其他地区较为一致,有效半径主要位于7~15μm,液态水含量(liquid water content,LWC)主要分布在0.01~0.3 g/m^(3),但墨脱地区过冷水的分布比其他地区更为丰富,往往云顶、云底及云中同时存在过冷水。The identification of supercooled liquid water(SLW)in clouds,is important for artificially influencing weather and preventing aircraft from freezing.However,it has always been a difficult area of meteorological sounding.Millimeter-wave radar is an effective tool for the continuous detection of cloud structures and physical features.Based on the observations from a Ka-band millimeter radar and a microwave radiometer in Mêdog,which is located at the entrance of the water vapor passage in southeastern Tibetan Plateau,a threshold method and a fuzzy logic algorithm were used to identify hydrometer phase in clouds,including ice,snow,SLW,and mixed phase.Two stratocumulus cloud cases were selected to analyze the effect of SLW identification.The SLW identification results were analyzed and initially assessed by comparing their liquid water paths(LWPs)with that from collocated microwave radiometer.Results showed that the SLW areas identified by both the fuzzy logic method and the threshold method are basically reasonable,and the fuzzy logic method can identify more SLW areas.From In terms of quantitative evaluation,the LWP of SLW from fuzzy logic method is closer to that from microwave radiometer than that form threshold method.The effective radius of SLW in stratocumulus clouds in Mêdog ranges from 7 to 15μm and the values of liquid water content are between 0.01 and 0.3 g/m^(3),which are relatively consistent with those in other regions.However,the distribution of SLW in Mêdog is usually located in cloud tops,cloud bottoms,and midclouds at the same time,which is more abundant than that in other areas.

关 键 词：藏东南 毫米波云雷达 过冷水 模糊逻辑法 阈值法 液态水路径 

分 类 号：P407.7[天文地球—大气科学及气象学]