Sensitivity of the reference evapotranspiration to key climatic variables during the growing season in the Ejina oasis northwest China.
The standardized FAO56 Penman-Monteith model, which has been the most reasonable method in both humid and arid climatic conditions, provides reference evapotranspiration (ETo) estimates for planning and efficient use of agricultural water resources. And sensitivity analysis is important in understanding the relative importance of climatic variables to the variation of reference evapotranspiration. In this study, a non-dimensional relative sensitivity coefficient was employed to predict responses of ETo to perturbations of four climatic variables in the Ejina oasis northwest China. A 20-year historical dataset of daily air temperature, wind speed, relative humidity and daily sunshine duration in the Ejina oasis was used in the analysis. Results have shown that daily sensitivity coefficients exhibited large fluctuations during the growing season, and shortwave radiation was the most sensitive variable in general for the Ejina oasis, followed by air temperature, wind speed and relative humidity. According to this study, the response of ETo can be preferably predicted under perturbation of air temperature, wind speed, relative humidity and shortwave radiation by their sensitivity coefficients.
Geographic Information and Tourism Department, Chuzhou University, Chuzhou, China.
Lan-Gong
LG
Hou
Key Laboratory of Eco-hydrology and River Basin Science, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, No. 260 West Donggang Road, Lanzhou, China.
Song-Bing
SB
Zou
Key Laboratory of Eco-hydrology and River Basin Science, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, No. 260 West Donggang Road, Lanzhou, China.
Hong-Lang
HL
Xiao
Key Laboratory of Eco-hydrology and River Basin Science, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, No. 260 West Donggang Road, Lanzhou, China.
Yong-Gang
YG
Yang
China; Ejina oasis; FAO Penman-Monteith model; Reference evapotranspiration; Sensitivity coefficient