气象学报2024，Vol.82Issue(3)：306-318,13.DOI:10.11676/qxxb2024.20230072
2021年7月20-22日豫北地区暴雨过程中尺度低涡和垂直运动发展的位涡动力学诊断
Potential vorticity diagnosis of a mesoscale vortex development and associated vertical motions during the 20-22 July 2021 torrential rainfall in northern Henan
摘要
Abstract
A persistent torrential rain process occurred in Henan province from 17 to 23 July 2021(hereafter referred to as Henan"21.7"torrential rain).During 20-22 July,the center of the Henan"21.7"torrential rain moved to northern Henan,causing severe floods in Xinxiang,Hebi and other places on the east side of the Taihang mountains.Based on rainfall observations collected at automatic weather stations and ERA5 atmospheric reanalysis product,the thermodynamic mechanism for the mesoscale vortex and vertical motion development during the torrential rain event in northern Henan is diagnosed by using the Potential Vorticity(PV)tendency equation and the vertical motion decomposition method.The results show that the atmospheric diabatic heating caused by latent heat release during the precipitation process increased with height in the middle and lower troposphere,leading to the genesis of local PV and the development of mesoscale vortex.On the other hand,an intensified mesoscale vortex caused the isentropic surfaces to become more concave with more inclined surface,which enhanced the convergence and uplift of large-scale warm and moist southeasterlies in northern Henan.In particular,the isentropic-gliding ascending motion and the ascending motion induced by condensational latent heat release intensified,leading to further increases in precipitation.Therefore,the positive feedback loop formed between the mesoscale vortex and vertical motion and heavy precipitation development,resulting in the persistent torrential rain process in northern Henan.关键词
河南暴雨/位涡/垂直运动/非绝热加热/中尺度低涡Key words
Henan heavy rain/Potential vorticity/Vertical motion/Diabatic heating/Mesoscale vortex分类
天文与地球科学引用本文复制引用
刘柯,毛江玉,汪小康,生宸,张冠舜,任靖..2021年7月20-22日豫北地区暴雨过程中尺度低涡和垂直运动发展的位涡动力学诊断[J].气象学报,2024,82(3):306-318,13.基金项目
国家自然科学基金项目(42175076、42230612、41705019)、湖北省自然科学基金联合基金项目(2023AFD092)、湖北省气象局科技发展基金项目(2022Q04)、中国气象局武汉暴雨研究所基本科研业务费(202302). （42175076、42230612、41705019）
