Estimating reference crop evapotranspiration with elevation based on an improved HS model
Estimating reference crop evapotranspiration with elevation based on an improved HS model
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基于改进的 HS 模型估算随海拔变化的参考作物蒸散量
DOI：
10.2166/nh.2018.022
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发表时间：
2019
期刊：
影响因子：
--
通讯作者：
Wang Chaozi
中科院分区：
文献类型：
--
作者：
Tang Pengcheng;Xu Bing;Gao Zhanyi;Li Heping;Gao Xiaoyu;Wang Chaozi
西藏高海拔地区ET 0的估算面临着独特的挑战：监测站的稀缺，气象数据的短时覆盖，低氧和低压环境，以及强烈的太阳辐射。利用西藏20个典型观测点30 a逐日气象资料，利用海拔因子和修正的温度常数对Hargreaves（HS）模式进行了改进。改进后的模型--Hargrest-Elevation（HS-E）改进模型在不同时间尺度上都能得到较好的结果。在HS模型中，当应用于高海拔地区时，负ET 0值是不可避免的。然而，HS-E模型解决了这个问题，提高了估计ET 0的准确性。特别地，当时间尺度变大时，HS-E模型表现得更好。因此，在气象资料缺乏的高海拔地区，如西藏海拔2,000 m以上地区，推荐使用HS-E模式估算ET 0。
Estimation of ET0 in high-elevation (above sea level, ASL) areas of Tibet presents unique challenges: scarcity of monitoring stations, short-time coverage of meteorological data, low-oxygen and low-pressure environment, and strong solar radiation. In this study, altitude factors and modified temperature constants are utilized to improve the Hargreaves (HS) model based on 30-year daily meteorological data from 20 typical sites in Tibet. The improved model, Hargreaves-Elevation (HS-E) improved model, could provide better results at different time scales. Negative ET0 values were unavoidable in the HS model when applied to high-elevation areas. However, the HS-E model solved this problem and improved the accuracy of estimated ET0. In particular, the HS-E model performs better when the time scale becomes larger. Therefore, the HS-E model is highly recommended to estimate ET0 in high-elevation areas where the meteorological data are scarce, for example, in Tibet above 2,000 m.