摘要
采用逐日降水资料,计算2008年汛期(4～6月)降水量和洪涝指数。分析表明,汛期全省总降水量略偏少,无明显的大范围洪涝发生,呈现出南多北少、前少后多的时空分布特征。应用500hPa月平均高度场及距平场、西北太平洋副高特征量、海温、南海季风指数及前期气候资料,对2008年汛期降水特点进行了环流背景分析及预测研究。结果表明:北半球极涡中心强度偏弱,中纬度西风带北支锋区较为平直、位置偏北,副高偏弱、偏东、偏北是2008年汛期降水偏少的主要环流背景。汛期降水量存在着明显的周期变化,2000年以来处于少雨阶段、娜尼拉事件发生、南海季风爆发日期偏早、上年秋季降水偏少等,均是汛期降水偏少的预测强信号。
The precipitation and floods index in Rainy Season in Jiangxi Province in 2008 are calculated by using the daily rainfall data. The results show that the total rainfall in rainy season over the province is further scanty. No-flooding occurred obviously, and the flooding is characterized by the feature of southern more/northern less and front less/back more. Based on the monthly mean 500hpa geopotential heights and anomalies data, the northwest Pacific subtropical high characteristics data, SST data, South China Monsoon index data and the previous climatic data, the circulation background of precipitation characteristics in rainy season in 2008 are analyzed and researched. The results show that the main circulation backgrounds of scanty rainfall in rainy season include the weak center intensity of polar vortex indexes in the Northern Hemisphere, the even-straight northern frontal zone of westerly belt in the middle latitude region and the further north position, the further weak-east -north subtropical high. The change of precipitation in rainy season has the obvious periods. Since 2000, the scanty rainfall period, La Nina occurrence, earlier onset of South China Monsoon and the further scanty rainfall in autumn of the last year are the strong predicted signal of further scanty rainfall in rainy season.
出处
《科技广场》
2009年第3期19-22,共4页
Science Mosaic
基金
2009年江西省气象科技创新基金"江西省春季低温阴雨预测技术研究"资助
关键词
降水特征
环流背景
预测研究
Precipitation Characteristics
Circulation Background
Prediction Research
