摘要
利用1959—2011年北半球500 hPa高度格点资料、74项环流特征量资料和1974—2011年NOAA OLR月平均资料,结合江西83个气象观测站的1959—2011年4月降水资料,对2011年4月江西降水异常偏少成因进行了初步诊断分析。结果表明:江西省4月降水有一定的周期性,2011年4月降水处于少雨期;La Ni觡a次年4月西太平洋副热带高压强度易偏弱,位置正常或偏南、偏东,导致向北输送的暖湿气流较常年明显偏弱;大西洋—欧洲环流呈E型分布,青藏高原位势高度明显偏高;赤道西太平洋附近对流活动偏强,我国大陆及东南沿海、赤道中太平洋东部附近对流活动偏弱是造成降水明显偏少的主要原因。
Using 1959—2011 500 hPa height data,74 circulation parameters,1974—2011 monthly average outgoing long-wave radiation（OLR） data of NOAA,and 83 stations rainfall data of Jiangxi in April,the cause of precipitation less than normal is analyzed.The results show that the rainfall in April varies periodically,and the rainfall in April 2011 was in the dry period.The western Pacific subtropical high lay to the east or south of the normal position and its intensity was always weaker,which resulted weaker warm and humid air transporting northward.The Atlantic-Europe circulation pattern showed E shape and the potential height over the Tibetan Plateau was relatively higher.The negative OLR anomaly region appeared over the west tropical Pacific,and the positive OLR region was over east of the equatorial central Pacific and the southeast of China.
出处
《气象与减灾研究》
2011年第4期16-22,共7页
Meteorology and Disaster Reduction Research
基金
江西省科技支撑计划项目(编号:2008BB30700)
关键词
降水异常
LaNi觡a
副热带高压
OLR
Precipitation anomaly
La Nia
Subtropical high
Outgoing long-wave radiation（OLR）.
