potential evapotranspiration (ET0),parametric equation; Penman-Monteith method,spatial interpolation ,"/> <span class="Char">A Simplified Method and Its Application for Estimating Potential Evapotranspiration</span>

Arid Zone Research ›› 2019, Vol. 36 ›› Issue (6): 1431-1439.

Previous Articles     Next Articles

A Simplified Method and Its Application for Estimating Potential Evapotranspiration

ZHANG Ying1, 2, HAO Xing-ming1, HUA Ding1, 2, SUN Hai-tao1, 2, LI Yu-peng1, 2   

  1. 1. Stake Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, Xinjiang, China;
    2. University of Chinese Academy of Sciences, Beijing 100049, China

  • Received:2018-12-05 Revised:2019-01-15 Online:2019-11-15 Published:2019-11-15

Abstract:

 Potential evapotranspiration plays an important role in estimating the regional water balance and crop water demand and also assessing drought. However, the spatial interpolation of potential evapotranspiration is always a challenge for relevant researches. In this study, a simple parametric model was used to achieve the spatialization of the potential evapotranspiration (ET0) in Xinjiang based on the observed data from 66 meteorological stations in Xinjiang from 1960 to 2017. The results indicated that: ① There was a certain regularity of spatial distribution of the two important parameters a and c of the simplified parametric model. The parameter a was spatially high in the southeast but low in the northwest of Xinjiang. The parameter c, however, was increased with the increase of altitude; ②Compared with the Penman-Monteith method, the R2 values of the simplified parametric model at the daily, monthly and seasonal scales were all higher than 0.9, and they were increased with the increase of time scale; ③The compared results between the fitting results of the simplified parametric model and the CRU data and MOD16A2 data revealed that the R2 values of the simplified parametric model and of the Penman-Monteith method were high, the fitting results and errors were better, but the R2 values fitted with CRU and MOD16A2 were low. Moreover, the accuracy of potential evapotranspiration and the spatial resolution (500 m×500 m) obtained by the simplified parametric model were high. Therefore, the simplified parametric model is a convenient and effective model for calculating the ET0 at regional scale, and can be applied to estimate the potential evapotranspiration in Xinjiang.

Key words: potential evapotranspiration (ET0)')">

potential evapotranspiration (ET0), parametric equation; Penman-Monteith method, spatial interpolation