NUMERICAL EXPERIMENTS ON THE INFLUENCES OF GENERAL CIRCULATION ANOMALY OVER THE TIBETAN PLATEAU AND SURFACE ALBEDO CHANGE IN NORTHWEST CHINA ON SUMMER PRECIPITATION  

作　　者：孙国武 俞亚勋 王宝灵 冯建英 

机构地区：[1]Lanzhou Arid Meteorological Institute,Lanzhou 730020

出　　处：《Acta meteorologica Sinica》1998年第3期311-320,共10页

摘　　要：An advanced three-level global atmospheric general circulation model has been used to study the summer precipitation anomaly in Northwest China.based on the synoptic fact and the statistical analysis of the precipitation,the surface albedo in Northwest China,and the synoptic systems over the Tibetan(Qinghai-Xizang)Plateau.The results show that either the anticyclone intensified over the plateau or the surface alhedo enhanced in Northwest China results in summer precipitation reduction east of Northwest China.Especially.when both of them appear simultaneously,summer precipitation was obviously reduced and severe drought occurred in most areas of Northwest China.Moreover.the simulated difference of precipitation rate of Northwest China is similar to the actural precipitation distribution in Northwest China in 1995,which is the most severe drought year in Northwest China in the past fifty years.So the tendency in drought severity intensified,drought frequency accelerated,drought persistence period extended,and drought areas expanded in Northwest China in recent years is maybe a result of the influences of human activities(e.g.vegetation was reduced,and desertification worsened)on drought circulation pattens over the Tibetan Plateau.An advanced three-level global atmospheric general circulation model has been used to study the summer precipitation anomaly in Northwest China.based on the synoptic fact and the statistical analysis of the precipitation,the surface albedo in Northwest China,and the synoptic systems over the Tibetan(Qinghai-Xizang)Plateau.The results show that either the anticyclone intensified over the plateau or the surface alhedo enhanced in Northwest China results in summer precipitation reduction east of Northwest China.Especially.when both of them appear simultaneously,summer precipitation was obviously reduced and severe drought occurred in most areas of Northwest China.Moreover.the simulated difference of precipitation rate of Northwest China is similar to the actural precipitation distribution in Northwest China in 1995,which is the most severe drought year in Northwest China in the past fifty years.So the tendency in drought severity intensified,drought frequency accelerated,drought persistence period extended,and drought areas expanded in Northwest China in recent years is maybe a result of the influences of human activities(e.g.vegetation was reduced,and desertification worsened)on drought circulation pattens over the Tibetan Plateau.

关 键 词：Tibetan Plateau Northwest China general circulation model(GCM) surface albedo change 

分 类 号：P435[天文地球—大气科学及气象学]