Variation in reference crop evapotranspiration caused by the Angstrom-Prescott coefficient: Locally calibrated versus the FAO recommended

文献类型： 外文期刊

第一作者： Liu, Xiaoying

作者： Liu, Xiaoying;Mei, Xurong;Li, Yuzhong;Wang, Qingsuo;Zhang, Yanqing;Porter, John Roy

作者机构：

关键词： Reference crop evapotranspiration;Angstrom-Prescott coefficients;Penman-Monteith

期刊名称：AGRICULTURAL WATER MANAGEMENT （ 影响因子：4.516； 五年影响因子：5.12 ）

ISSN： 0378-3774

年卷期： 2009 年 96 卷 7 期

页码：

收录情况： SCI

摘要： Accurate estimation of the reference crop evapotranspiration (ETo) is investigated due to its critical role in affecting calculation of crop water use and efficiency in agricultural ecosystems. The main emphasis in this paper is to clarify the possible uncertainty in the estimation of ET0 associated with using uncalibrated Angstrom-Prescott (A-P) coefficients. We first calibrated the coefficients using long-term data records from 34 sites in the Yellow River basin in China, and then applied these coefficients to estimate short wave irradiance (R-s) and ET0 at 16 sites to evaluate the difference in ET0 between the FAO recommended and the locally calibrated. We found that the direct use of the FAO recommended coefficients significantly affected the estimation of ET0 at most sites, which differed from -3% to 15% at daily scale and from -4% to 16% at monthly scale from the locally calibrated ones. These differences are comparable with or larger than those caused by some alternatives of the FAO recommended algorithms for net irradiance or vapor pressure, which further highlights the importance of using the locally calibrated coefficients. The degree of difference in ET0 showed a significant threshold relation with altitude and longitude in such a way that relatively small impact lies around 2233 m and 98 degrees E, and away from these, the effect begins to increase. Given the large overestimation in water use as a consequence of the significant overestimation in ET0 associated with the direct use of the FAO coefficients, especially in those high yield production areas with altitude <1200 m, we developed several relationships between the A-P coefficient a, b, (a + b) and other easily obtainable factors (altitude, longitude and air temperature). A three-step procedure was recommended in applying these relations, which was (1) determine if calibration is needed or not for a given location; (2) estimate one of the A-P coefficients, either a or b if calibration is needed; (3) estimate the remaining coefficient using relations of(a + b) due to its higher coefficient of determination. In summary, we have revealed the errors and areas that are most affected when using the un-calibrated coefficients, and discussed the consequence of such error on agricultural production, and proposed practical solutions to avoid large errors. These results are intended to make the research community aware of such errors so that more appropriate choice of these coefficients is made. We hope that similar assessment will be done in other climates, contributing to managing water resources efficiently in water basins. (C) 2009 Elsevier B.V. All rights reserved.

分类号：

  • 相关文献

[1]Comparison of 16 models for reference crop evapotranspiration against weighing lysimeter measurement. Liu, Xiaoying,Xu, Chunying,Zhong, Xiuli,Li, Yuzhong,Cao, Jingfeng,Yuan, Xiaohuan.

[2]Choice of the Angstrom-Prescott coefficients: Are time-dependent ones better than fixed ones in modeling global solar irradiance?. Liu, Xiaoying,Mei, Xurong,Li, Yuzhong,Wang, Qingsuo,Zhang, Yanqing,Porter, John Roy. 2010

[3]Calibration of the Angstrom-Prescott coefficients (a, b) under different time scales and their impacts in estimating global solar radiation in the Yellow River basin. Liu, Xiaoying,Mei, Xurong,Li, Yuzhong,Zhang, Yanqing,Wang, Qingsuo,Jensen, Fens Raunso,Porter, John Roy. 2009

[4]Performance of the Priestley-Taylor equation in the semiarid climate of North China. Liu, XY,Lin, E. 2005

[5]Comparison of satellite-based evapotranspiration models over terrestrial ecosystems in China. Chen, Yang,Xia, Jiangzhou,Feng, Jinming,Wang, Kaicun,Yuan, Wenping,Chen, Yang,Xia, Jiangzhou,Liang, Shunlin,Li, Xianglan,Wang, Kaicun,Chen, Yang,Xia, Jiangzhou,Liang, Shunlin,Li, Xianglan,Wang, Kaicun,Liang, Shunlin,Feng, Jinming,Ma, Zhuguo,Zhao, Tianbao,Fisher, Joshua B.,Li, Xin,Wen, Jun,Liu, Shuguang,Miyata, Akira,Mu, Qiaozhen,Sun, Liang,Tang, Jianwei,Zhang, Qiang,Xue, Yueju,Yu, Guirui,Zha, Tonggang,Zhang, Li,Zhao, Liang,Yuan, Wenping.

[6]Spatiotemporal Distribution of Calibration Coefficients of Hargreaves Equation for Estimating Potential Evapotranspiration in Mainland China. Long, Huaiyu,Lei, Qiuliang,Zhang, Renlian,Shuai, Xiufu,Shuai, Xiufu.

[7]Improving a Penman-Monteith evapotranspiration model by incorporating soil moisture control on soil evaporation in semiarid areas. Sun, Liang,Liang, Shunlin,Yuan, Wenping,Sun, Liang,Liang, Shunlin,Yuan, Wenping,Sun, Liang,Liang, Shunlin,Yuan, Wenping,Liang, Shunlin,Chen, Zhongxin.

[8]Estimation of regional evapotranspiration over the Southern Great Plains based on Penman-Monteith theory and the soil moisture estimates. Sun Liang. 2014

作者其他论文 更多>>

微信小程序