江淮梅雨丰、枯梅年水汽输送差异特征  

CHARACTERS OF THE WATER VAPOR TRANSFER IN THE CHANGJIANG-HUAIHE RIVERS VALLEY

作　　者：毛文书[1] 王谦谦[2] 李国平[1] 朱克云[1] 

机构地区：[1]成都信息工程学院大气科学学院,四川成都610225 [2]南京信息工程大学大气科学学院,江苏南京210044

出　　处：《热带气象学报》2009年第2期234-240,共7页Journal of Tropical Meteorology

基　　金：国家自然科学基金项目“青藏高原低涡空心及螺旋云带的观测和理论研究“(40875023);我国温度和降水气候极端事件及其与全球不均匀增暖的联系”(40675042);国家重点基础研究发展计划(973)项目“我国南方致洪暴雨监测与预测的理论和方法研究”(2004CB418300);成都信息工程学院科研基金项目(CRF200801)共同资助

摘　　要：利用江淮流域1954—2001年梅雨量资料和美国NCEP/NCAR 1954—2001年逐日高度场、风场、比湿场和地面气压场资料,网格距2.5°×2.5°,采用模糊聚类、合成分析等方法,详细讨论了江淮梅雨丰、枯梅年垂直积分的整层纬向、经向和水汽通量输送差异特征。结果表明:区域梅雨量指数能很好地揭示出江淮流域梅雨量的丰枯;丰梅年西太平洋副高南侧的偏南气流和其北侧的偏北气流水汽输送显著增强,越赤道气流抵达北半球后,集中在10°N附近,40～130°E范围内的阿拉伯海和孟加拉湾向北偏东方向伸展,与来自南海和西太平洋的水汽输送相汇合,在我国的江淮流域-日本列岛南部形成一条水汽通量距平≥55 kg/(m.s)的强水汽输送带;丰梅年水汽通量散度距平表明:整层水汽通量辐合比枯梅年明显加强,为江淮梅雨提供了充沛的水汽来源,有利于江淮梅雨的异常偏多;枯梅年则反之。Based on the precipitation during Meiyu at 37 stations in the Changjiang-Huaihe rivers valley and the mean daily reanalysis geopotential height, wind field, humidity field and surface pressure field data （Grid 2.5 ° × 2.5 °） from 1954 to 2001, the difference characteristics of zonal, meridional and the whole layer water vapor transfer in the Changjiang-Heuanhe river valley are studied in terms of the fuzzy cluster analysis, composite analysis, and so on. The results show that there are significant difference characters of the zonal, meridional and the whole layer water vapor transfer in the corresponding period between the wet meiyu years and dry meiyu years by means of regional meiyu index calculated. The water vapor transfers of the subtropical high in the south and north are marked by an increase over the Changjiang-Huaihe region, The air current crossing the equator from Southern Hemisphere arrives in Northern Hemisphere gathers in areas around 10 °N, 40 to 130 °E and extends to the northwest and converges with the south-north air current from Arabian sea, Bay of Bengal and subtropical high to form a strong southern air current that extends to the northeast from the ChangJiang-Huaihe region to North Japan. The narrow scope forms a strong belt of convergence （The flux of water vapor transfers is greater than 55 kg/（m-s）） that extends to the adjacent international dateline from the Changjiang-Huaihe Valley to Japan archipelagic islands in the wet Meiyu years, which provides large-scale water vapor and is advantageous of increasing of Meiyu precipitation and vice versa in dry Meiyu years.

关 键 词：江淮梅雨 区域梅雨量指数 模糊聚类 水汽通量 水汽输送 

分 类 号：P458[天文地球—大气科学及气象学]