Estimating reference crop evapotranspiration with elevation based on an improved HS model
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 tempera...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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IWA Publishing
2019-02-01
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| Series: | Hydrology Research |
| Subjects: | |
| Online Access: | http://hr.iwaponline.com/content/50/1/187 |
| _version_ | 1818341713919344640 |
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| author | Pengcheng Tang Bing Xu Zhanyi Gao Heping Li Xiaoyu Gao Chaozi Wang |
| author_facet | Pengcheng Tang Bing Xu Zhanyi Gao Heping Li Xiaoyu Gao Chaozi Wang |
| author_sort | Pengcheng Tang |
| collection | DOAJ |
| description | 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. |
| first_indexed | 2024-12-13T16:03:10Z |
| format | Article |
| id | doaj.art-1a93923eddae46258645a5d1b7a3dfab |
| institution | Directory Open Access Journal |
| issn | 1998-9563 2224-7955 |
| language | English |
| last_indexed | 2024-12-13T16:03:10Z |
| publishDate | 2019-02-01 |
| publisher | IWA Publishing |
| record_format | Article |
| series | Hydrology Research |
| spelling | doaj.art-1a93923eddae46258645a5d1b7a3dfab2022-12-21T23:39:06ZengIWA PublishingHydrology Research1998-95632224-79552019-02-0150118719910.2166/nh.2018.022022Estimating reference crop evapotranspiration with elevation based on an improved HS modelPengcheng Tang0Bing Xu1Zhanyi Gao2Heping Li3Xiaoyu Gao4Chaozi Wang5 State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, Beijing 100038, China and China Institute of Water Resources and Hydropower Research, Beijing 100038, China Institute of Water Resources for Pastoral Area, China Institute of Water Resources and Hydropower Research, Hohhot 010020, China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, Beijing 100038, China and China Institute of Water Resources and Hydropower Research, Beijing 100038, China Institute of Water Resources for Pastoral Area, China Institute of Water Resources and Hydropower Research, Hohhot 010020, China Water Conservancy and Civil Engineering College, Inner Mongolia Agricultural University, Hohhot 010018, China Department of Land, Air, and Water Resources, UC Davis, Davis, CA 95616, USA 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.http://hr.iwaponline.com/content/50/1/187hargreaves-elevation modelhargreaves modelhigh-elevation areaspenman-monteith equationreference crop evapotranspirationtibet |
| spellingShingle | Pengcheng Tang Bing Xu Zhanyi Gao Heping Li Xiaoyu Gao Chaozi Wang Estimating reference crop evapotranspiration with elevation based on an improved HS model Hydrology Research hargreaves-elevation model hargreaves model high-elevation areas penman-monteith equation reference crop evapotranspiration tibet |
| title | Estimating reference crop evapotranspiration with elevation based on an improved HS model |
| title_full | Estimating reference crop evapotranspiration with elevation based on an improved HS model |
| title_fullStr | Estimating reference crop evapotranspiration with elevation based on an improved HS model |
| title_full_unstemmed | Estimating reference crop evapotranspiration with elevation based on an improved HS model |
| title_short | Estimating reference crop evapotranspiration with elevation based on an improved HS model |
| title_sort | estimating reference crop evapotranspiration with elevation based on an improved hs model |
| topic | hargreaves-elevation model hargreaves model high-elevation areas penman-monteith equation reference crop evapotranspiration tibet |
| url | http://hr.iwaponline.com/content/50/1/187 |
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