摘要
利用1979—2021年ERA5再分析资料,将中国秋冬季寒潮分为全国、北方和南方寒潮,分析其中阻塞型寒潮路径和环流特征。结果表明:乌拉尔山(乌山)的背景经向位涡梯度分布导致了阻塞高压的位置与强度的不同,全国阻塞型寒潮大部分由强大的乌拉尔山阻塞高压主导;北方阻塞型寒潮为大西洋阻塞;部分南方阻塞型寒潮阻塞高压在乌山地区,部分存在于大西洋。大多数全国和南方阻塞型寒潮的冷空气路径为西北型路径,两者环流过程类似,在乌山有着反气旋异常,在东亚地区有着西北-东南向的波列,但是南方阻塞型的环流和冷空气强度较弱,而仅能对温度较高的南方造成强降温。北方阻塞型寒潮通过波能量的传播在贝加尔湖以西激发出反气旋异常,寒潮爆发后,当贝加尔湖南部的横槽明显东移或者反气旋强度不减反增都可以令冷空气沿西方型路径移动。
Using the ERA5 reanalysis data from 1979 to 2021,the autumn and winter cold surges are divided into national,northern and southern cold surges.The characteristics of the blocking cold surge paths and circulation are analyzed.The location and strength of the blocking high are influenced the distribution of background meridional potential vorticity gradient in Ural Mountains.The most national blocking cold surges are dominated by the Ural high,while northern blocking cold surges' blockings are in Atlantic,partly southern blocking cold surges' blockings are in the Ural Mountains and partly in the Atlantic.For most of national and southern blocking cold surge,their paths are west-north type.Their circulation are similar,that is,there is the strong anticyclonic anomaly in Ural Mountain and the wave train with northwest-southeast direction in East Asia.But due to its weak circulation and weak cold air,it can only cause strong cooling in the south with higher temperature.For the northern blocking cold surges,there is the anticyclonic anomaly in west of Lake Baikal through the propagation of wave energy.If the horizontal trough has an obvious eastward movement or the anticyclonic anomaly are stronger after cold surge breaks out,the cold air will move in the west path.
作者
邵建红
刁一娜
Shao Jianhong;Diao Yinan(Department of Meteorology,College of Oceanic and Atmospheric Sciences,Ocean University of China,Qingdao 266100,China)
出处
《中国海洋大学学报（自然科学版）》
CAS
CSCD
北大核心
2023年第4期145-158,共14页
Periodical of Ocean University of China
基金
山东省自然科学基金重大基础研究项目(ZR2019ZD12)
国家重点研究发展计划项目(2019YFA0607002)
国家自然科学基金项目(42075025)资助。
关键词
中国寒潮
经向位涡梯度
阻塞高压
自组织映射网络
Chinese cold surge
meridional potential vorticity gradient
blocking high
self-organizing maps
