摘要
利用常规气象资料分析了2009年早春苏南地区连阴雨期间的降水特点和环流形势特征。分析表明,此次连阴雨过程具有持续时间特别长、降水量特别多、最高气温偏低、雷暴天气频发等特点。连阴雨期间,欧亚上空高层中高纬环流经历贝湖低槽型、阻塞型和一槽一脊型3个阶段,亚洲中纬度地区多短波槽东移,保证了连阴雨天气的冷空气来源。孟加拉湾南支槽活跃,西太平洋副高偏北,从南海和菲律宾海经副高外围气流的水汽输送是此次连阴雨天气的主要水汽来源。由于冷暖空气在长江下游持续的相互作用,造成了苏南地区长达21天的阴雨天气。
Based on the routine weather chart data,the rainfall characteristics and circulation features of a continuous rainfall in the southern Jiangsu Province in early spring of 2009 are analyzed.It is shown that the consecutive rainfall had some unusual characteristics,such as prolonged duration,enormous precipitation,low maximum air temperature,and frequent thunderstorms.During the rainfall event,the upper-level circulation over Eurasia in the middle or high latitudes came through three stages： Baikal trough type,blocking type,and one trough and one ridge type.Several short-wave troughs split up and moved toward east in mid-latitudes of Asia,which ensured the sources of cold air.The Bengal trough was active;the subtropical high over the West Pacific was farther northern than normal;and the water vapor was transported mainly by the outer edge air flow of the subtropical high from the South China Sea and Philippine Sea.As cold and warm air interacted constantly on the lower Yangtze Valley,the consecutive rainfall event of 21 days long formed.
出处
《气象科技》
2012年第2期274-279,共6页
Meteorological Science and Technology
关键词
连阴雨
环流形势
阻塞高压
consecutive rainfall
circulation pattern
blocking anticyclone
