Extensive Cold-Precipitation-Freezing Events in Southern China and Their Circulation Characteristics  

作　　者：Jing-Bei PENG Cholaw BUEH Zuo-Wei XIE 

机构地区：[1]Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029,China

出　　处：《Advances in Atmospheric Sciences》2021年第1期81-97,共17页大气科学进展（英文版）

基　　金：This research was funded by the National Natural Science Foundation of China(Grant Nos.41975072 and 41675086);the National Science and Technology Support Program of China(Grant No.2015BAC03B03).

摘　　要：Concurrence of low temperature,precipitation and freezing weather in an extensive area would cause devastating impacts on local economy and society.We call such a combination of concurrent disastrous weather“extensive coldprecipitation-freezing”events(ECPFEs).In this study,the ECPFEs in southern China(15°−35°N,102°−123°E)are objectively defined by using daily surface observational data for the period 1951−2013.An ECPFE in southern China is defined if the low temperature area,precipitation area and freezing area concurrently exceed their respective thresholds for at least three consecutive days.The identified ECPFEs are shown to be reasonable and reliable,compared with those in previous studies.The circulation anomalies in ECPFEs are characterized by a large-scale tilted ridge and trough pairing over mid-and high-latitude Eurasia,and the intensified subtropical westerlies along the southern foot of the Tibetan Plateau and the anomalous anticyclonic circulation over the subtropical western Pacific.Comparative analysis reveals that the stable cold air from the north and the warm and moist air from the south converge,facilitating a favorable environment for the concurrence of extensive low-temperature,precipitation and freezing weather.

关 键 词：extensive cold-precipitation-freezing event southern China large-scale tilted ridge and trough trough over the Bay of Bengal western Pacific subtropical high 

分 类 号：P434[天文地球—大气科学及气象学] P426.6