灾害学2013，Vol.28Issue(1)：6-10,27,6.
2011年陕西秋季强连阴雨天气的大气环流异常特征分析
Analysis on Anomalous Characteristics of Atmospheric Circulation of the Strong Continuous Rainfall in Shaanxi Province during Autumn 2011
摘要
Abstract
Using NCEP/NCAR reanalysis data, the anomalous characteristics of Eurasian Atmospheric Circulation related to the strong continuous rainfall in Shaanxi province of China during autumn 2011 are analyzed. The results show that; precipitation intensity, wide range of heavy rain and precipitation concentration are features of the strong continuous rainfall. A North high-South low distribution in the Eurasian 500 hPa height anomaly field provides a favorable atmospheric circulation background for the strong continuous rainfall. Due to stable maintaining of a blocking high at 500 hPa between Ural Mountains to Central Asia, the northerly flow in front of ridge leads cool air to move from the high to southern Mongolia. Therefore, a cold tongue is finally formed between Lake Baikal and Lake Balkhash. Meanwhile, a stronger, more eastern, more northern western Pacific subtropical high remains stably. In this way, the northwestern cold air moves southeastward persistently and meets the warm air near the Qinling Mountains, which leads to continuous rainfall in Shaanxi province. Moreover, an anomalous cyclonic circulation and the corresponding strong southeasterly air flow occur at 700 hPa east of Taiwan Island, leading sufficient water vapor transported to central China including Shaanxi province. In addition, during the strong continuous rainfall period, the stable western Pacific subtropical high and the stimulated vertical movement in right front of the entrance of subtropical upper-level jet stream create a good dynamic environment field for the strong continuous rainfall in Shaanxi province.关键词
连阴雨/大气环流/秋季/陕西Key words
continuous rainfall, atmospheric circulation, Shaanxi province/ autumn分类
天文与地球科学引用本文复制引用
方建刚,易俊莲..2011年陕西秋季强连阴雨天气的大气环流异常特征分析[J].灾害学,2013,28(1):6-10,27,6.基金项目
中国科学院知识创新工程重要方向项目(KZCX2-EW-114) （KZCX2-EW-114）
中国科学院国家外专局创新团队国际合作伙伴计划(KZZD-EW-TZ-03) （KZZD-EW-TZ-03）
国家重点基础研究发展规划项目(2010CB833406) （2010CB833406）
