长江三角洲地区GPS大气可降水量统计特征分析  

Statistical Analysis of Atmospheric Precipitable Water Vapour Observed by GPS in Yangtze River Delta Region

作　　者：杨引明[1] 朱雪松[1] 刘敏[1] 丁金才[1] 沈愈[2] 

机构地区：[1]上海市卫星遥感与测量应用中心,上海201100 [2]上海市气候中心,上海200030

出　　处：《高原气象》2008年第B12期150-157,共8页Plateau Meteorology

基　　金：国家自然科学基金项目(40505011);上海市科委重点科技攻关项目(75115011)共同资助

摘　　要：利用近7年来(2002—2008年)长江三角洲地区地基GPS网观测的大气可降水量资料,分析了长江三角洲地区大气可降水量的气候特征,重点对梅雨期的大气可降水量特征及其与强降水的关系进行了分析。结果表明:长江三角洲地区PWV分布总体呈南高北低、西高东低的分布特征,夏半年平均PWV高于冬半年20 mm左右,且长江三角洲地区南北向水汽梯度大于东西向,说明偏南气流对该地区的水汽输送作用较明显;PWV存在显著的季节变化特征,大气可降水量最大值均出现夏季的8月份,最小值出现冬季的1月份,且春、秋季节内各月间的PWV变化幅度较大,而夏、冬季内各月间的PWV变化较稳定;其次,长江三角洲地区PWV没有显著周期性年际变化和日变化特征。此外,PWV与梅雨期强降水量之间有明显关联,当梅雨期PWV值迅速由低值上升到60 mm以上时,或在强降水之后,PWV值并没有明显回落,仍然维持在高值时,极容易产生强降水,这为长江三角洲地区强降水量预报提供了一种新的信号。The climate features of atmospheric water vapor in Yangtze River Delta region are analyzed by use of 7 years＇ Precipitable Water Vapor（PWV） data observed by GPS observational Network, and the relations between climate characteristics of Atmospheric Precipitable Water vapor and heavy rain in Meiyu season are also studied. The results show that： PWV distribution in the Yangtze River Delta region are the higher the north and higher the west, the average PWV during summer months are higher than that of the winter months about 20mm, and the PWV gradient from south to north is clearly higher than that from west to east, which shows that moisture transported to Yangtze River Delta region by northern flow is important. PWV in Yangtze River Delta region has a significant seasonal change, the maximum PWV are found in August in summer, and the minimum PWV occurred in January in winter, and the PWV changes in spring and autumn are strong than that in summer and winter; while the PWV in Yangtze River Delta region has no significant cyclical changes in year and in day. In addition, there is obvious correlation between PWV and severe precipitation during Meiyu Period, when the PWV value quickly increase from the low--value to more than 60 mm, or PWV values remained at high values after severe precipitation, severe precipitation often occurs, which maybe provides a new signal for us to forecasts heavy rain in the Yangtze River Delta.

关 键 词：长江三角洲 全球定位系统(GPS) 大气可降水量 梅雨期 强降水 

分 类 号：P426.615[天文地球—大气科学及气象学]