藏东“三江流域”近30a气候变化及气象灾害特征

The Characteristics of Climate Change and Meteorological Disasters in the Eastern Tibet Three-River Valley in Nearly 30 Years

近30年来藏东“三江流域”的年平均气温的变化特征与全区的变化趋势相一致,总的变化特征是呈平稳上升趋势,年平均气温以0.42℃/10a的速率增温,年降水量呈较弱的增加趋势,增幅为22.0 mm/10a。降水的年际变化波动较大,从年际间的波动可见流域气候旱涝状况交替出现。气象灾害的种类及其出现的频率分析结果表明:出现频率最高的是暴雨洪涝为23%,其次是雪灾、干旱和泥石流分别占15%,冰雹、霜冻和病虫害分别占9%和7%。

The characteristics of the change of the annual average temperature in the eastern Tibet three-river valley and the change trend of the whole are stable in nearly 30 years. The general characteristics are rising steadily. Annual average temperature is increasing at a rate of about 0.42?C/10a;the growth of annual rainfall is weak;and the increasing trend of growth is 22.0 mm/10a. The variability of precipitation fluctuation is big and we can infer the change of basin climate drought and flood. The analysis of the types and frequency of meteorological disasters shows that storm flood has the highest frequency about 23%;snow storms, droughts and mud-slides are the second about 15% respectively;and hail and frost as well as plant diseases and in-sect pests are about 9% and 7% respectively.