摘要
2011年3月环流特征如下:北半球极涡呈绕极型,强度较常年同期偏强,中高纬度环流呈4波型,南支槽略偏强,西北太平洋副热带高压强度偏弱,位置偏东。全国平均降水量为20.4 mm,比常年同期偏少27%,为近10年来历史同期最少;受冷空气、南支槽及西北太平洋副高的影响,月内共有7次主要的降水过程,较强的雨雪天气过程主要集中在中旬与下旬。月平均气温为2.4℃,较常年同期温度偏低0.8℃,为近23年来最低值。月内共有2次冷空气过程影响我国大部地区,甘肃东部、四川西部、西藏东部及云南西北部等地遭受雪灾、泥石流等灾害。
The following are the main characteristics of the general atmospheric circulation in March 2011. There is a strong polar vortex centre in the Northern Hemisphere.The circulation presents a four-wave pattern in middle-high latitudes.The south branch trough is slightly stronger than the normal,and the Northwestern Pacific subtropical high（NPSH） is slightly weaker.The regional averaged precipitation for whole China is 20.4 mm,and 27%less than the normal,which is the least in the past ten years.There are 7 main precipitation processes,which mainly occurred in the second and the last dekad,induced by cold surge,south branch trough,and NPSH.The monthly mean temperature is 2.4℃,and 0.8℃lower than the normal,which is the lowest in the past 23 years.There are two cold surge processes affecting most areas of China,which result in the disasters,such as snow storm and sand slides in east of Gansu and east of Tibet,northwest of Yunnan,and west of Sichuan.
出处
《气象》
CSCD
北大核心
2011年第6期756-763,共8页
Meteorological Monthly
基金
公益性行业(气象)科研专项(GYHY201106003)
关键词
冷空气
暴雪
低温
大气环流
天气分析
cold surge
severe snow
low temperature
atmospheric circulation
weather analysis
