| This paper taking Yanqi Basin as an example, using the calculated ET0 value by PM model as standard, has evaluated the applicability of H-S, P-T and McCloud models in study area. The results showed that: The total solar radiation with the ET0 value has shown a very strong correlation(r=0.937) and partial correlation(r=0.962). It explained that the solar radiation energy was the main impact factor to the ET0. In the calculation of ET0 value, the calculated result by H-S model was significant higher than the PM model, the P-T and McCloud models were significant less than PM model. Among them, the calculated accuracy was the highest by the H-S model, the , root mean square error was 0.836 mm, the average deviation was 0.638 mm. Through modification to the H-S, P-T and McCloud models, the calculation precision for different models total obtained improvement. The modified P-T model obtained the highest accuracy (RMSE was 0.613 mm, Nash-Sutcliffe E was 0.6821), the ET0 value by three modified models had no significant differences with PM model. |