Abstract: By using the precipitation data of 10 observation stations in Weifang City from 1961 to 2005,the four seasons in Weifang city and the inter-annual and decadal variation characteristics of the precipitation were analyzed with climatologically statistical diagnosis.The results showed that the annual precipitation had great variation and showed obvious decreasing trend.The inter-annual seasonal precipitation decreased,but the decrease amplitude was obviously different.The inter-annual precipitation in summer was the most serious among four seasons,the decreasing was the most obvious and it had important impact on the variation of annual atmospheric water resource in the whole year.The periodic variation of precipitation in Weifang city was analyzed by using MORLET wavelet analysis.It showed that the inter-annual scale and inter-decade scale periodic variation of the average year and season precipitation had significant change in last 45 years.The water resources current situation in Weifang City was analyzed,the results showed that economic sustainable development was restricted by the severe water shortage in Weifang city.

Key words: Weifang city, Inter-annual, Decadal, Water resource, Wavelet analysis