HTG-4型微波辐射计资料在贵阳机场夏季2次雷雨天气中的应用分析

【目的】该文旨在研究微波辐射计资料在雷雨天气的分析与预报中所发挥的作用。【方法】利用贵阳站探空数据、微波辐射计资料、常规观测资料、ERA5 0.250.25再分析资料,采用统计、对比和诊断分析的方法,探讨贵阳机场HTG-4型微波辐射计的探测效果,并对2022年夏季贵阳机场2次雷雨天气进行对比分析。【结果】微波辐射计探测资料与探空站数据的整体相关性较高,其对机场上空气温和低空露点的探测比较可靠。机场两次雷雨期间,微波辐射计探测到上空大气转为“上干冷、下暖湿”的温湿分布,IWV、LWP、LPR值出现激增,能量指数有显著波动,雷雨结束后IWV、LWP、LPR值快速回落,能量指数回归稳定状态,微波辐射计资料更为灵敏、直观地展现了雷雨期间温湿条件的变化。【结论】系统性雷雨与局地热对流的触发机制和水汽含量有所不同,微波辐射计对系统性雷雨的起止及演变可做到约20min的预警提前量,但对局地热对流的开始和结束则很难提前预警。

Application Analysis of HTG-4 Microwave Radiometer Data in Two Summer Thunderstorms at Guiyang Airport

This paper aims to study the role of microwave radiometer data in the analysis and prediction of thunderstorm weather. Using the sounding data from Guiyang observation station, and the microwave radiometer data, conventional observation data as well as ERA5 0.250.25 reanalysis data, we investigate the detection effect of HTG-4 microwave radiometer at Guiyang Airport and analyze the two thunderstorm processes at Guiyang Airport in summer 2022 by means of statistics, comparison and diagnostic analysis. The results show that the overall correlation of the microwave radiometer detection data and the sounding station data is high, and the detection of the temperature and low dew point above the airport is more reliable. During the two thunderstorms at the airport, the microwave radiometer detected that the atmosphere aloft turned into a distribution of "dry and cold above, warm and wet below", the values of IWV, LWP and LPR surged, and the energy index fluctuated significantly. After the thunderstorm ended, the values of IWV, LWP and LPR dropped rapidly, and the energy index returned to a stable state. The microwave radiometer data can show the changes of temperature and humidity conditions during a thunderstorm more sensitively and intuitively. So, it is concluded that the triggering mechanism and water vapor content of systemic thunderstorms and local geothermal convection are different. The microwave radiometer can provide about 20 min advance warning for the start, end and evolution of systemic thunderstorms, but it is difficult to give advance warning for the start and end of local thermal convection.