Estimation of evaporation over the upper Blue Nile basin by combining observations from satellites and river flow gauges
Reliable estimates of regional evapotranspiration are necessary to improve water resources management and planning. However, direct measurements of evaporation are expensive and difficult to obtain. Some of the difficulties are illustrated in a comparison of several satellite-based estimates of evap...
| Main Authors: | , , , |
|---|---|
| Other Authors: | |
| Format: | Article |
| Language: | en_US |
| Published: |
American Geophysical Union
2017
|
| Online Access: | http://hdl.handle.net/1721.1/110307 https://orcid.org/0000-0001-6955-0025 https://orcid.org/0000-0003-0739-7242 |
| _version_ | 1826205031766949888 |
|---|---|
| author | Allam, Mariam M. Jain Figueroa, Anjuli McLaughlin, Dennis Eltahir, Elfatih A. B. |
| author2 | Parsons Laboratory for Environmental Science and Engineering (Massachusetts Institute of Technology) |
| author_facet | Parsons Laboratory for Environmental Science and Engineering (Massachusetts Institute of Technology) Allam, Mariam M. Jain Figueroa, Anjuli McLaughlin, Dennis Eltahir, Elfatih A. B. |
| author_sort | Allam, Mariam M. |
| collection | MIT |
| description | Reliable estimates of regional evapotranspiration are necessary to improve water resources management and planning. However, direct measurements of evaporation are expensive and difficult to obtain. Some of the difficulties are illustrated in a comparison of several satellite-based estimates of evapotranspiration for the Upper Blue Nile (UBN) basin in Ethiopia. These estimates disagree both temporally and spatially. All the available data products underestimate evapotranspiration leading to basin-scale mass balance errors on the order of 35 percent of the mean annual rainfall. This paper presents a methodology that combines satellite observations of rainfall, terrestrial water storage as well as river-flow gauge measurements to estimate actual evapotranspiration over the UBN basin. The estimates derived from these inputs are constrained using a one-layer soil water balance and routing model. Our results describe physically consistent long-term spatial and temporal distributions of key hydrologic variables, including rainfall, evapotranspiration, and river-flow. We estimate an annual evapotranspiration over the UBN basin of about 2.55 mm per day. Spatial and temporal evapotranspiration trends are revealed by dividing the basin into smaller subbasins. The methodology described here is applicable to other basins with limited observational coverage that are facing similar future challenges of water scarcity and climate change. |
| first_indexed | 2024-09-23T13:05:59Z |
| format | Article |
| id | mit-1721.1/110307 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T13:05:59Z |
| publishDate | 2017 |
| publisher | American Geophysical Union |
| record_format | dspace |
| spelling | mit-1721.1/1103072022-10-01T13:02:16Z Estimation of evaporation over the upper Blue Nile basin by combining observations from satellites and river flow gauges Allam, Mariam M. Jain Figueroa, Anjuli McLaughlin, Dennis Eltahir, Elfatih A. B. Parsons Laboratory for Environmental Science and Engineering (Massachusetts Institute of Technology) Allam, Mariam M. Jain Figueroa, Anjuli McLaughlin, Dennis Eltahir, Elfatih A. B. Reliable estimates of regional evapotranspiration are necessary to improve water resources management and planning. However, direct measurements of evaporation are expensive and difficult to obtain. Some of the difficulties are illustrated in a comparison of several satellite-based estimates of evapotranspiration for the Upper Blue Nile (UBN) basin in Ethiopia. These estimates disagree both temporally and spatially. All the available data products underestimate evapotranspiration leading to basin-scale mass balance errors on the order of 35 percent of the mean annual rainfall. This paper presents a methodology that combines satellite observations of rainfall, terrestrial water storage as well as river-flow gauge measurements to estimate actual evapotranspiration over the UBN basin. The estimates derived from these inputs are constrained using a one-layer soil water balance and routing model. Our results describe physically consistent long-term spatial and temporal distributions of key hydrologic variables, including rainfall, evapotranspiration, and river-flow. We estimate an annual evapotranspiration over the UBN basin of about 2.55 mm per day. Spatial and temporal evapotranspiration trends are revealed by dividing the basin into smaller subbasins. The methodology described here is applicable to other basins with limited observational coverage that are facing similar future challenges of water scarcity and climate change. 2017-06-27T15:03:42Z 2017-06-27T15:03:42Z 2016-01 2015-03 Article http://purl.org/eprint/type/JournalArticle 0043-1397 http://hdl.handle.net/1721.1/110307 Allam, Mariam M.; Jain Figueroa, Anjuli; McLaughlin, Dennis B. and Eltahir, Elfatih A. B. “Estimation of Evaporation over the Upper Blue Nile Basin by Combining Observations from Satellites and River Flow Gauges.” Water Resources Research 52, 2 (February 2016): 644–659 © 2016 American Geophysical Union https://orcid.org/0000-0001-6955-0025 https://orcid.org/0000-0003-0739-7242 en_US http://dx.doi.org/10.1002/2015wr017251 Water Resources Research Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf American Geophysical Union MIT Web Domain |
| spellingShingle | Allam, Mariam M. Jain Figueroa, Anjuli McLaughlin, Dennis Eltahir, Elfatih A. B. Estimation of evaporation over the upper Blue Nile basin by combining observations from satellites and river flow gauges |
| title | Estimation of evaporation over the upper Blue Nile basin by combining observations from satellites and river flow gauges |
| title_full | Estimation of evaporation over the upper Blue Nile basin by combining observations from satellites and river flow gauges |
| title_fullStr | Estimation of evaporation over the upper Blue Nile basin by combining observations from satellites and river flow gauges |
| title_full_unstemmed | Estimation of evaporation over the upper Blue Nile basin by combining observations from satellites and river flow gauges |
| title_short | Estimation of evaporation over the upper Blue Nile basin by combining observations from satellites and river flow gauges |
| title_sort | estimation of evaporation over the upper blue nile basin by combining observations from satellites and river flow gauges |
| url | http://hdl.handle.net/1721.1/110307 https://orcid.org/0000-0001-6955-0025 https://orcid.org/0000-0003-0739-7242 |
| work_keys_str_mv | AT allammariamm estimationofevaporationovertheupperbluenilebasinbycombiningobservationsfromsatellitesandriverflowgauges AT jainfigueroaanjuli estimationofevaporationovertheupperbluenilebasinbycombiningobservationsfromsatellitesandriverflowgauges AT mclaughlindennis estimationofevaporationovertheupperbluenilebasinbycombiningobservationsfromsatellitesandriverflowgauges AT eltahirelfatihab estimationofevaporationovertheupperbluenilebasinbycombiningobservationsfromsatellitesandriverflowgauges |