Analysis on climate change feature of Beijing during 1951 to 2006

Based on the temperature and precipitation data during 1951—2006 of national outdoor weather station in Beijing,annual and seasonal variation characteristics were analyzed with regression and trend lines.The results show that:(1)General temperature of Beijing showed ascendant trend with rate of 0.41℃ /10a and the added value was 2.3℃.The temperature seasonal change showed a rising trend,which similar to annual variation.Winter had a highest added value with rate of 0.057℃ /a.Spring and Autumn had higher added values with rates of 0.047℃ /a and 0.036℃ /a.Summer had the lowest added value with rate of 0.028℃ /a.(2)The annual precipitation of Beijing during 56 years decreased by a rate of 4.96 mm/10a,with the absolute value of 27.78 mm.There are differences between seasonal precipitation change.Spring had a weak increasing.On the opposite,seasonal precipitation change had similar trend to annual precipitation change among summer,Autumn and Winter.Summer obviously reduced with rate of 15 mm/a.Autumn and Winter clearly reduced with rates of 1.5 mm/a and 0.2 mm/a.