Comparative Study of Hydrology and Icemelt in Three Nepal River Basins Using the Glacio-Hydrological Degree-Day Model (GDM) and Observations From the Advanced Scatterometer (ASCAT)
An assessment of the water supply and its seasonal and annual changes over the century in the High Mountain Asia (HMA) region is of increasing interest due to its potential impact on one-sixth of the global population. In order to understand the changing hydrology and snow and ice melt, we used remo...
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Frontiers Media S.A.
2020-01-01
|
| Series: | Frontiers in Earth Science |
| Subjects: | |
| Online Access: | https://www.frontiersin.org/article/10.3389/feart.2019.00354/full |
| _version_ | 1811277619948158976 |
|---|---|
| author | Rijan Bhakta Kayastha Nicholas Steiner Rakesh Kayastha Shruti K. Mishra Kyle McDonald Kyle McDonald |
| author_facet | Rijan Bhakta Kayastha Nicholas Steiner Rakesh Kayastha Shruti K. Mishra Kyle McDonald Kyle McDonald |
| author_sort | Rijan Bhakta Kayastha |
| collection | DOAJ |
| description | An assessment of the water supply and its seasonal and annual changes over the century in the High Mountain Asia (HMA) region is of increasing interest due to its potential impact on one-sixth of the global population. In order to understand the changing hydrology and snow and ice melt, we used remotely sensed Advanced Scatterometer (ASCAT) observations of glacier melt (GM) and a distributed and gridded Glacio-hydrological Degree-day Model (GDM) in three river basins: Tamor, Trishuli and Marsyangdi. The GDM-estimated contribution of snowmelt, icemelt, rainfall and baseflow in river flows is found to be most accurate in the Trishuli River basin, with Nash-Sutcliffe efficiency (NSE) between the estimated and observed discharges of 0.81 and volume differences of −0.5%, and reasonably accurate in the Tamor River basin, with NSE of 0.69 and volume difference of −7.51%. Similarly, NSE of 0.81 and volume difference of 4.64% in Marsyangdi River basin. We find strong similarities in the timing of glacier melting using the GDM and from observations from the ASCAT GM, determining the seasonal start of glacier melting to within 6 days on average. In all basins ASCAT GM observes melting at higher elevations relative to GDM, average of 5,328 m a.s.l. Systematic differences in glacier melting area determined by modeling and satellite observations indicate ASCAT may have suboptimal resolution, view geometry and/or polarimetry for delineating glacier melting at the process-scale in complex topography, especially in the ablation zone. This is the first step in examining the remote sensing products that could potentially be incorporated into hydrologic models to increase the accuracy of the hydrologic flow as well as the ability to estimate river discharge in other basins with limited data. |
| first_indexed | 2024-04-13T00:20:01Z |
| format | Article |
| id | doaj.art-4d9f0af7ff604b6cb4d6458ef33681b1 |
| institution | Directory Open Access Journal |
| issn | 2296-6463 |
| language | English |
| last_indexed | 2024-04-13T00:20:01Z |
| publishDate | 2020-01-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Earth Science |
| spelling | doaj.art-4d9f0af7ff604b6cb4d6458ef33681b12022-12-22T03:10:48ZengFrontiers Media S.A.Frontiers in Earth Science2296-64632020-01-01710.3389/feart.2019.00354469221Comparative Study of Hydrology and Icemelt in Three Nepal River Basins Using the Glacio-Hydrological Degree-Day Model (GDM) and Observations From the Advanced Scatterometer (ASCAT)Rijan Bhakta Kayastha0Nicholas Steiner1Rakesh Kayastha2Shruti K. Mishra3Kyle McDonald4Kyle McDonald5Himalayan Cryosphere, Climate and Disaster Research Center (HiCCDRC), Department of Environmental Science and Engineering, School of Science, Kathmandu University, Dhulikhel, NepalDepartment of Earth and Atmospheric Sciences, The City College of New York, The City University of New York, New York, NY, United StatesHimalayan Cryosphere, Climate and Disaster Research Center (HiCCDRC), Department of Environmental Science and Engineering, School of Science, Kathmandu University, Dhulikhel, NepalArgonne National Laboratory, Lemont, IL, United StatesDepartment of Earth and Atmospheric Sciences, The City College of New York, The City University of New York, New York, NY, United StatesEarth and Environmental Sciences Program, The Graduate Center, The City University of New York, New York, NY, United StatesAn assessment of the water supply and its seasonal and annual changes over the century in the High Mountain Asia (HMA) region is of increasing interest due to its potential impact on one-sixth of the global population. In order to understand the changing hydrology and snow and ice melt, we used remotely sensed Advanced Scatterometer (ASCAT) observations of glacier melt (GM) and a distributed and gridded Glacio-hydrological Degree-day Model (GDM) in three river basins: Tamor, Trishuli and Marsyangdi. The GDM-estimated contribution of snowmelt, icemelt, rainfall and baseflow in river flows is found to be most accurate in the Trishuli River basin, with Nash-Sutcliffe efficiency (NSE) between the estimated and observed discharges of 0.81 and volume differences of −0.5%, and reasonably accurate in the Tamor River basin, with NSE of 0.69 and volume difference of −7.51%. Similarly, NSE of 0.81 and volume difference of 4.64% in Marsyangdi River basin. We find strong similarities in the timing of glacier melting using the GDM and from observations from the ASCAT GM, determining the seasonal start of glacier melting to within 6 days on average. In all basins ASCAT GM observes melting at higher elevations relative to GDM, average of 5,328 m a.s.l. Systematic differences in glacier melting area determined by modeling and satellite observations indicate ASCAT may have suboptimal resolution, view geometry and/or polarimetry for delineating glacier melting at the process-scale in complex topography, especially in the ablation zone. This is the first step in examining the remote sensing products that could potentially be incorporated into hydrologic models to increase the accuracy of the hydrologic flow as well as the ability to estimate river discharge in other basins with limited data.https://www.frontiersin.org/article/10.3389/feart.2019.00354/fullglacio-hydrological modeldegree-day factorsnow and ice meltdischargeadvanced scatterometer |
| spellingShingle | Rijan Bhakta Kayastha Nicholas Steiner Rakesh Kayastha Shruti K. Mishra Kyle McDonald Kyle McDonald Comparative Study of Hydrology and Icemelt in Three Nepal River Basins Using the Glacio-Hydrological Degree-Day Model (GDM) and Observations From the Advanced Scatterometer (ASCAT) Frontiers in Earth Science glacio-hydrological model degree-day factor snow and ice melt discharge advanced scatterometer |
| title | Comparative Study of Hydrology and Icemelt in Three Nepal River Basins Using the Glacio-Hydrological Degree-Day Model (GDM) and Observations From the Advanced Scatterometer (ASCAT) |
| title_full | Comparative Study of Hydrology and Icemelt in Three Nepal River Basins Using the Glacio-Hydrological Degree-Day Model (GDM) and Observations From the Advanced Scatterometer (ASCAT) |
| title_fullStr | Comparative Study of Hydrology and Icemelt in Three Nepal River Basins Using the Glacio-Hydrological Degree-Day Model (GDM) and Observations From the Advanced Scatterometer (ASCAT) |
| title_full_unstemmed | Comparative Study of Hydrology and Icemelt in Three Nepal River Basins Using the Glacio-Hydrological Degree-Day Model (GDM) and Observations From the Advanced Scatterometer (ASCAT) |
| title_short | Comparative Study of Hydrology and Icemelt in Three Nepal River Basins Using the Glacio-Hydrological Degree-Day Model (GDM) and Observations From the Advanced Scatterometer (ASCAT) |
| title_sort | comparative study of hydrology and icemelt in three nepal river basins using the glacio hydrological degree day model gdm and observations from the advanced scatterometer ascat |
| topic | glacio-hydrological model degree-day factor snow and ice melt discharge advanced scatterometer |
| url | https://www.frontiersin.org/article/10.3389/feart.2019.00354/full |
| work_keys_str_mv | AT rijanbhaktakayastha comparativestudyofhydrologyandicemeltinthreenepalriverbasinsusingtheglaciohydrologicaldegreedaymodelgdmandobservationsfromtheadvancedscatterometerascat AT nicholassteiner comparativestudyofhydrologyandicemeltinthreenepalriverbasinsusingtheglaciohydrologicaldegreedaymodelgdmandobservationsfromtheadvancedscatterometerascat AT rakeshkayastha comparativestudyofhydrologyandicemeltinthreenepalriverbasinsusingtheglaciohydrologicaldegreedaymodelgdmandobservationsfromtheadvancedscatterometerascat AT shrutikmishra comparativestudyofhydrologyandicemeltinthreenepalriverbasinsusingtheglaciohydrologicaldegreedaymodelgdmandobservationsfromtheadvancedscatterometerascat AT kylemcdonald comparativestudyofhydrologyandicemeltinthreenepalriverbasinsusingtheglaciohydrologicaldegreedaymodelgdmandobservationsfromtheadvancedscatterometerascat AT kylemcdonald comparativestudyofhydrologyandicemeltinthreenepalriverbasinsusingtheglaciohydrologicaldegreedaymodelgdmandobservationsfromtheadvancedscatterometerascat |