Comparisons of Temperature-Based Models for Reference Crop Evapotranspiration Forecasting

• 作 者: Jian Lu Yufeng Luo Xiyun Jiao Xiaomin Chang Kaihua Bai Qianwen Nie Yuanlai Cui
• 机 构: StateKeyLaboratoryofHydrology-WaterResourcesandHydraulicEngineering,HohaiUniversity,Nanjing210098,Ch
• 出 处: 2015中国农业水土资源保护与自然农法国际论坛
• 发表日期: 2015年7期
• 关键词: irrigation forecast irrigation scheduling reference evapotranspiration temperatu

　　Accurate daily reference crop evapotranspiration (ET0) forecasts are helpful for real-time irrigation scheduling.We compared the original and calibrated versions of four temperature-based models, Hargreaves-Samani (HS), Thornthwaite (TH), reduced set FAO-56 Penman-Monteith (PT) and McCloud (MC), for ET0 forecasting using forecasted temperatures.Daily meteorological data were collected to calculate ET0 using the FAO-56 Penman-Monteith (PM) model, and the temperature forecasts for 1 to 7-day lead time and the four models were employed to forecast the ET0.The models were evaluated through comparisons between the ET0 forecasts and ET0 calculated from observed meteorological data and the PM model.The accuracy of temperature forecasts from public weather forecasts was high overall, and the error in minimum temperature forecasts was less than the error in maximum temperature forecasts.The values of statistical indices indicated that the performance of ET0 forecasting of the HS and TH models were similar and they were better than the PT model, and the MC model yielded the lowest performance.For the HS and TH models, the average values of accuracy were 86.4% and 86.9%, MAE 0.77 mm · d-1 and 0.76 mm · d-1, RMSE 1.05 mm · d-1 and 1.02 mm · d-1 and R 0.84 and 0.82.For Huaian Station, we tended to recommend the HS model for ET0 forecasting due to its high performance and ease of use.