Evaluating Reference Crop Evapotranspiration (<i>ETo</i>) in the Centre of Guanzhong Basin—Case of Xingping & Wugong, Shaanxi, China
- 1 Civil Engineering Department, College of Water Resources and Architectural Engineering, Northwest A&F University, Yangling, China
- 2 College of Water Resources and Architecture Engineering, Northwest A&F University, Yangling, Chin
Abstract
In this paper, the Penman-Monteith method was applied to evaluate the reference crop evapotranspiration. A reliable estimation of the reference evapotranspiration ( ET o ) is of critical importance and required accurate estimates to close the water balance. The aim of this paper is estimating the reference evapotranspiration ( ET o ) as preliminary to use for groundwater modeling in the area. Based on FAO-Penman-Monteith method, ET o calculator software was applied. Meteorological data within this study were obtained from two gauges stations (Xing ping and Wu gong) and available literatures. The results indicated that the values of ET o for a period (1981-2009) — 29 years — in two stations approximately the same. Specifically, is ranged between 0.4 - 6.9 mm /day, 0.4 - 6.7 mm/day and the average value is 2.6 mm/ day, 2.6 mm/day in Xing ping and Wu gong respectively. In addition, the maximum values were occurred in summer season (May, June and July). The result also found that the correlation coefficient ≈ 1. Moreover, “ ET o ” was increasing by recent years. The reference crop evapotranspiration for some crops were calculated.
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