2013年10月大气环流和天气分析

Analysis of the October 2013 Atmospheric Circulation and Weather

2013年10月环流特征如下:北半球高纬度地区为单一极涡,强度较常年同期偏强,中高纬环流呈现4波型,北美地区中高纬环流经向度较常年偏大,南支槽偏强,西太平洋副热带高压强度偏强。10月,全国平均降水量为30.8 mm,比常年同期(35.8 mm)偏少14.0%,全国平均气温为11.1℃,比常年同期(10.3℃)偏高0.8℃。月内,冷空气活动频繁,先后有4次冷空气过程影响我国,但只有22—26日的冷空气达到全国较强冷空气标准,其他3次都是影响北方的中等强度冷空气;受台风菲特影响,我国华东地区南部和华南地区北部出现一次强降水过程;江南中部及河南等地气象干旱持续或发展;我国中东部大部地区出现雾霾天气。

The following are the main characteristics of the general atmospheric circulation in October2013.There is one strong polar vortex center over the Northern Hemisphere.The circulation presents a four-wave pattern in middle high latitudes.The meridional circulation is more obvious,the south branch trough and the West Pacific subtropical high are stronger than normal years.The monthly mean precipitation is 30.8 mm,14%less than normal.The monthly mean temperature is 11.1℃,which is 0.8℃ lower than normal years.There are four cold air processes affecting China during this month.Typhoon Fitow makes landfall in southern part of East China and northern part of South China,bringing a severe rainfall process.The autumn drought across the central part of Jiangnan Region and Henan Province continues or develops.Besides,most parts of the central and eastern China suffers from fog and haze events.