2021年11月大气环流和天气分析

Analysis of the November 2021 Atmospheric Circulation and Weather

2021年11月大气环流的主要特征为:北半球极涡显著偏强,欧亚中高纬环流呈纬向多波动型,冷空气活跃,东亚大槽和西太平洋副热带高压均偏西偏强。11月,全国平均降水量为23.8 mm,比常年同期(18.8 mm)偏多26.7%;全国平均气温为2.9℃,与常年同期持平。月内气温冷暖起伏较大,出现了2次全国型寒潮过程和3次大范围持续性雾-霾天气过程。其中4—9日的寒潮天气过程具有影响范围广、降温幅度大、大风持续时间长、北方暴雪极端性强等特点。

The main characteristics of the general atmospheric circulation in November 2021 are as follows.The polar vortex in the Northern Hemisphere is significantly strong.The Eurasian mid-and high-latitude circulation had a latitudinal multi-fluctuation pattern.Cold air was extremely active.Both East Asian trough and the western Pacific subtropical high were westward and strong.The monthly mean precipitation(23.8 mm)over China was 26.7%more than normal(18.8 mm).The monthly average temperature was 2.9℃,similar to the normal years.Cold and warm temperatures fluctuate greatly during the month.There were two nationwide cold wave processes and three widespread persistent fog-haze weather processes.Among them,the cold wave weather process from 4 to 9 November had the characteristics of a wide range of influence,sharp drop in temperature,long duration of strong winds and extreme blizards in northern China,etc.