2015年10月大气环流和天气分析

Analysis of the October 2015 Atmospheric Circulation and Weather

2015年10月大气环流特征如下:北半球极地地区存在单极涡,极涡强度较常年同期偏强。中高纬环流为4波型,西太平洋副热带高压位置明显偏西,强度偏强。10月全国平均降水量为39.5 mm,较常年同期(35.8 mm)偏多10.3%;全国平均气温为11.0℃,较常年同期(10.3℃)偏高0.7℃。东北、华北和西北地区东部等地共计62站发生极端日降温事件。月内共有4次强降水过程,其中10月3—6日,广东中西部和广西东部出现暴雨天气过程。冷空气势力较强,共有4次主要冷空气过程影响我国。我国中东部出现3次大范围雾-霾天气。10月4日,今年第22号台风彩虹以强台风级在广东沿海登陆并造成重大影响,登陆强度追平历史纪录。

The main characteristics of the general atmospheric circulation in October 2015 are as follows： Over the Northern Hemisphere, there was one polar vortex center, which is more intense than usual. In the mid-high latitudes,the circulation presented a four-wave pattern. The West Pacific subtropic high system was stronger than usual, and its ridge extended to west obviously. The monthly mean precipitation was 39.5 mm, 10.3% higher than the climatological mean （35.8 mm）. Meanwhile, the monthly mean temperature was 11.0℃, which is 0.7℃ higher than its climatological mean （10.3℃）. In the Northeast, the Beijing-Tianjin--Hebei Region and the east of Northwest, 62 stations observed extrem temperature drop events. Four severe rainfall processes occurred during this month. The central and western part of Guangdong, and the east part of Guangxi went through a torrential rain process from 3 to 6 October. During this month, four cold air processes affected China. Central and eastern China suffered from three severe fog and haze events. On 4 October, Severe Typhoon ＂Mujigae＂ made landfall in Guangdong with in- tensity equal to the historic record, causing great losses.