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Based on the 51-year annual precipitation data of Ningbo from 1953 to 2003,a detailed analysis is performed by means of several diagnosis methods,including EOF,climatic abrupt change testing,Mexico hat wavelet and spectrum analysis.The results show that annual rainfall amount across the city tends to descend from the southwest to north-northeast,which accords with the topographic features of the city;the difference between maximum and minimum precipitation is about 400 mm.EOF1 of spatial characteristic vectors indicates that the annual precipitation of all the seven weather stations has a coincident tendency.Ningbo experienced an abrupt climate change in annual precipitation during the late 1960's and the early 1970's,and another significant change took place in recent years.The annual precipitation has been less than normal since the beginning of the 21st century with the minimum in 2003.There is a quasi-four year periodicity in annual precipitation.