Water vapour multi-vortex structure under the interactions of typhoons and mid-low latitude systems during extreme precipitation in North China  

作　　者：Jia-Hui TANG Xiang-De XU Wen-Yue CAI Chun-Zhu WANG 

机构地区：[1]Nanjing University of Information Science&Technology,Nanjing 210044,China [2]State Key Laboratory of Severe Weather,Chinese Academy of Meteorological Sciences,Beijing 100081,China [3]National Climate Center,China Meteorological Administration,Beijing 100081,China [4]Training Center,China Meteorological Administration,Beijing 100081,China

出　　处：《Advances in Climate Change Research》2023年第1期116-125,共10页气候变化研究进展（英文版）

基　　金：supported by the Second Tibetan Plateau Scientific Expedition and Research(STEP,2019QZKK0105)programme;the Development Fund of CAMS(2022KJ021).

摘　　要：With diverse atmospheric circulation and complex mechanisms,typhoon remote rainstorms(TRR)are closely related to a variety of mid-low latitude systems.The anomalous signatures in such processes can improve forecasting heavy rainfall associated with typhoons and fill the gaps in current physical conceptual models of TRR.Using the optimal typhoon path dataset,ground observation data,and the National Centres for Environmental Prediction(NCEP)reanalysis dataset,the impact of anomalous water vapour transport on excessive rainfall in North China is investigated.The vector empirical orthogonal function(VEOF)analysis is applied to typhoon precipitation events from 1970 to 2021,and three major modes are extracted to reflect the anomalous water vapour transport for typhoon precipitation.Mode 1 reflects a moisture circulation pattern in North China due to the coexistence of typhoons and remote and direct precipitation,with the highest probability of heavy precipitation.The differences in remote precipitation areas and intensities are attributed to the location of typhoons in the western North Pacific and the shifting of the subtropical high ridge.To characterise the water vapour transport circulation of TRR in North China,we proposed the‘multivortex’idea.The transmission of the multi-vortex ensures a continuous supply of TRR water vapour,and the enhancement of the multi-vortex is significantly linked to the enhancement of remote precipitation.Three extreme northern rainstorms,75·8 Henan,7·21 Beijing,and 7·20 Zhengzhou rainstorms,have anomalous multi-vortex water vapour convergence,similar to Mode 1.The mechanism of water vapour driven by multi-vortex in the three severe rainstorm events is more extreme than in usual TRR events in North China.The stronger Indian low vortex and relatively southerly subtropical highs can intensify the southwest branch of the double water vapour transport branch,whereas the strengthening of typhoons in the western North Pacific facilitates water vapour transport through the channel on

关 键 词：Typhoon remote rainstorm Mid-low latitude circulation systems Interaction Multi-vortex 

分 类 号：P426.6[天文地球—大气科学及气象学]