Satellite Observations of Reflectivity Maxima above the Freezing Level Induced by Terrain

作     者：Aoqi ZHANG Weibiao LI Shumin CHEN Yilun CHEN Yunfei FU Aoqi ZHANG;Weibiao LI;Shumin CHEN;Yilun CHEN;Yunfei FU

作者机构：Guangdong Province Key Laboratory for Climate Change and Natural Disaster StudiesSchool of Atmospheric SciencesSun Yat-sen UniversityGuangzhou 510275China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China 

出 版 物：《Advances in Atmospheric Sciences》 (大气科学进展（英文版）)

年 卷 期：2021年第38卷第4期

页      面：627-640页

核心收录：

学科分类：07[理学] 070601[理学-气象学] 0706[理学-大气科学] 

基　　金：supported by the Special Program for Key Research and Development of Guangdong Province (Grant Number 2019B111101002) the Fundamental Research Funds for the Guangzhou Science and Technology Plan project (Grant Number 201903010036) National Natural Science Foundation of China (Grant Numbers 41675043, 41775094, and 42005062) the Fundamental Research Funds for the Central Universities (Grant Number 20lgpy27) 

主　　题：orographic precipitation reflectivity maxima above the freezing level precipitation structure TRMM PR 

摘      要：Previous studies have recognized reflectivity maxima above the freezing level(RMAF) within stratiform precipitation over mountain slopes, however, quantitative studies are limited due to the lack of adequate identification criteria. Here, we establish an identification method for RMAF precipitation and apply it to the Tropical Rainfall Measuring Mission(TRMM) Precipitation Radar(PR) observations. Using the TRMM 2A25 product from 1998 to 2013, we show that the RMAF structure in reflectivity profiles can be effectively identified. RMAF exists not only in stratiform precipitation but also in convective precipitation. RMAF frequency is positively correlated with elevation, which is thought to be caused by enhanced updrafts in the middle layers of stratiform precipitation, or in the low to middle layers of convective precipitation over mountains. The average RMAF heights in stratiform and convective precipitation were 1.35 and 2.01 km above the freezing level, respectively, which is lower than previous results. In addition, our results indicate that the RMAF structure increased the echo top height and enhanced precipitation processes above the RMAF height, but it suppressed the downward propagation of ice particles and the near-surface rain rate. Future studies of orographic precipitation should take into account the impact of the RMAF structure and its relevant dynamic triggers.