Abstract:

The CLIGEN (Climate GENerator) weather generator is a part of the WEPP (Water Erosion Prediction Project) soil erosion model. It is mainly used to provide the daily meteorological data for a long sequence, thus to solve the problems of the shortage of actual metrological sequence or missing values. However, the adaptation of the CLIGEN model in Shenyang region of Northeast China needs to  be tested. In this paper, using daily station weather data in Shenyang from 1981 to 2001, the daily precipitation data were generated by the CLIGEN model. The daily, monthly, annual, and annual maximum daily precipitation of simulated and measured values were compared. The applicability of the model was evaluated using mean, standard deviation, skewness and kurtosis statistic data. The results show that the CLIGEN model generates  better simulation results for daily, monthly and annual precipitation amounts, The MARE (Mean Absolute Relative Error) is 2.1%,1.3%, and 3.3%, respectively. However, the simulation accuracy of annual maximum precipitation amount is slightly worse. As for the extreme values in precipitation, the simulation results of daily and annual maximum precipitation amounts are not good. The maximum error of daily and annual maximum precipitation amounts reaches to -27.2% and 18.3%, respectively. The CLIGEN model can better simulate the monthly and annual precipitation. Based on t, F and K-S tests, it indicates that only Kangping station reaches the very significant level in the daily and annual maximum daily precipitation amounts. In general, the CLIGEN model can better simulate the statistical characteristics of precipitation in Shenyang region.

Key words: Weather generator, CLIGEN, Precipitation, Interpolation, Test