Influence of climate change in Southern Xinjiang over last 50 years on available precipitation

Based on the monthly precipitation and temperature data from 1951 to 2006,the annual mean evaporation and the available precipitation in Southern Xinjiang were calculated.By analyzing the characteristics of changes in precipitation,temperature,evaporation and available precipitation over the last 50 years,the precipitation,temperature and available precipitation were simulated using the periodic analysis of stepwise regression.Then,they were predicted for the coming five years.The results show that the changes in temperature,precipitation and evaporation have basically had an increasing tendency since the 1970 s.However,the available precipitation has exhibited fluctuating characteristics,that is,relatively larger and smaller amounts than the average ones at different time.With climate change,the available precipitation does not necessarily increase,and it may decrease in Southern Xinjiang in the coming five years.