A Modified Hargreaves Equation by Free Search and Its Application in Harbin
The reference crop evapotranspiration(ET0) calculated from Hargreaves equation will be negative as the fixed parameters when mean air temperature is lower than -17.8C.To improve the application of Hargreaves equation, Free Search was employed to solve the parameters of modifying Hargreaves equations based on 48-year daily meteorological data of Harbin, and the evaluation of the modified Hargreaves equations were verified by three time steps of daily, ten-day and monthly. The research results showed that the modified Hargreaves equations could solve the problem on the negative ETo, and its accuracy is identical with the verifyied Hargreaves equations recommended by FAO,when ET0 values calculated from PenmanMonteith equation was taken as standard. And whats more, a simple method for developing Hargreaves equation was developed then.
reference crop evapotranspiration Penman-Monteith equation modified Hargreaves equation Free Search
Wang Bin Fu Qiang Wang Min Lei Chengrui
College of Water Conservancy and Building Engineering, Northeast Agricultural University, Harbin 150 Harbin Meteorological Administration, Harbin 150080, P. R. China
国际会议
山东淄博
英文
78-82
2011-05-27（万方平台首次上网日期，不代表论文的发表时间）