影响长江中下游夏季降水的前期潜在预报因子评估  

Evaluations of Prior Potential Predictors for the Summer Rainfall in the Middle and Lower Reaches of the Yangtze River

作　　者：郭玲[1,2] 何金海[1] 祝从文[2] 

机构地区：[1]南京信息工程大学气象灾害省部共建教育部重点实验室,南京210044 [2]中国气象科学研究院,北京100081

出　　处：《大气科学》2012年第2期337-349,共13页Chinese Journal of Atmospheric Sciences

基　　金：中国气象科学研究院重点基础科研项目2010Z001;2010Z003;国家自然基金资助项目40921003;公益性行业(气象)科研专项GY-HY200906017;GYHY200706005;中国科学院战略性先导科技专项--应对气候变化的碳收支认证及相关问题(XDA05090408)

摘　　要：利用1951～2006年美国NOAA海温资料、NCEP/NCAR再分析资料和青藏高原雪深等资料,根据前期海—陆—气因子对夏季长江流域降水的影响,本文搜集并整理了影响长江中下游夏季降水的40个预报因子,并讨论了前期因子与夏季降水在不同阶段的相关稳定性。通过相关和历史回报方法,讨论了前期关键因子与东亚夏季大气环流之间的关系和对夏季长江中下游降水的潜在预报能力。分析发现,冬季影响因子主要包括Nin珘o3区海温、黑潮海温、青藏高原积雪等外源强迫因子,而春季影响因子主要体现在北极涛动、极涡、西北太平洋副高等大气环流的异常。上述冬春影响因子与夏季长江中下游降水的相关呈现出年代际的变化特征,其中冬季黑潮海温、青藏高原积雪和贝加尔湖地表气温通过影响东亚夏季风环流系统,进而对夏季长江流域降水产生影响。综合考虑上述三个因子的权重时间变化,对1979年之后的夏季长江中下游降水具有较好的预报能力。In the framework of impacts of sea-land-atmosphere factors on the following summer rainfall in the middle and lower reaches of the Yangtze River （MLYR）, the authors reconstructed 40 factors on the basis of sea surface temperature （SST）, snow depth in the Tibetan Plateau, and NCEP/NCAR reanalysis datasets, and evaluated their possible impacts on the summer rainfall in the MLYR. Firstly, the authors discussed the stability of relationships between these factors and the following summer rainfall in the MLYR before and after 1979. Secondly, the authors selected several important factors by correlation analysis, and discussed the relationship between these factors and East Asian summer monsoon （EASM）. In addition, the potential forecast capability of these factors for the summer rainfall in the MLYR was discussed by historical hindcasts. The results suggest that the important winter predictors for the summer rainfall in the MLYR mainly come from the external forcing, such as the SST in Nio3 and Kuroshio Current regions, and the snow depth in Tibetan Plateau. In contrast, the potential spring predictors are almost the general circulation indices, such as Arctic Oscillation （AO）, polar vortex, and the western North Pacific subtropical high （WNPSH）. Running correlations between these potential predictors and the summer rainfall in the MLYR vary on interdecadal time scale, however, the SST in Kuroshio Current region, the snow depth in the Tibetan Plateau, and the surface air temperature near Lake Baikal show the significant antecedents for summer rainfall in the MLYR by affecting the EASM circulations, and jointly suggest the better forecast capability for the rainfall anomaly in the MLYR after 1979.

关 键 词：潜在预报因子 长江中下游降水 预报能力 

分 类 号：P426[天文地球—大气科学及气象学]