Abstract: As precipitation is one of the most important climatic data,accurate precipitation data plays a very important role on the research of related climate and hydrology in regional and global scale. The precipitation data is mainly from the precipitation observation records of meteorological stations. However,there are many uncertainties in observation records,and these uncertainties mainly come from three aspects: the inhomogeneity of spatial distribution of meteorological stations,the difference of the observation instrument type,method of installation and precipitation observation,and the system errors in the precipitation observation. In above three aspects, correcting the system error in precipitation observation is the feasible and effective way to improve the accuracy of the precipitation data. As the topography and climate types in Xinjiang are complex,the influence of the precipitation observation error on the accuracy of precipitation observation data is particularly prominent. Based on the data of hourly temperature,precipitation,wind speed,relative humidity and air pressure from 316 automatic weather stations,using the error correction method in precipitation observation proposed from a series of observation experiments organized by the World Meteorological Organization Solid Precipitation Measurement Inter Comparison Project at the Urumqi River Basin in China,and on the base of improving the accuracy of judgment method of precipitation types,the precipitation data during the summer half year (from April to October)of 2013 are analyzed and corrected at the aspects of wetting loss and wind-induced loss. Corrections for wetting loss in North Xinjiang are higher than those in South Xinjiang. The corrections for wetting loss in North Xinjiang are higher than those in South Xinjiang,and the corrections in the north slope of Tianshan Mountain are higher than those in the south slope. The corrections for wetting loss in the south slope decrease from north to south. The correction factors for wetting loss mainly range from 4.0% to 8.0% and from 8.0% to 12.0%. Corrections for wind-induced loss in North Xinjiang are higher than that in South Xinjiang. Corrections for wind-induced loss in the North Slope of Tianshan Mountain are higher than that in the south slope. Corrections for wind-induced loss in the south slope show a decreasing trend from north to south. The total correction of wetting loss and wind-induced loss in North Xinjiang is higher than that in South Xinjiang. The total correction factors of wetting loss and wind-induced loss do not show obvious spatial change characteristics on the whole,and mainly range from 15.0% to 20.0% and from 20.0% to 25.0%. The average value of precipitation increases by 16.96 mm after the correction of wetting loss and wind-induced loss.

Key words: Xinjiang, summer half year, precipitation, observation bias, correction