Analysis of Precipitation Change in Characteristic Laoha River Basin

This text is based on the daily precipitation data of 52 meteorological sites from 1964 to 2005,using the traditional methods,the difference product curves and the Kriging analysis of the trend of precipitation over the spatial and temporal in Laoha River Basin.The results show that the precipitation has a greater variability over the time and the space: the precipitation mainly concentrated in the summer months of 6,7,8,which accounts for 65%～75% of the annual precipitation;the precipitation has a slowly upward trend year by year,but the rain day has a trend of decreasing,the precipitation and rain day has a great positive correlation.The precipitation has a trend of declining from the southwest to the northeast,the precipitation which is more than 500mm mainly distributed in the northwest corner and the southwest corner,but the rain day is much less in the middle of the Laoha River Basin.The precipitation has a trend of enhance along with the elevation,when the elevation increases 1 kilometer the annual precipitation increases 116mm..