Benefits and pitfalls of GRACE data assimilation: A case study of terrestrial water storage depletion in India
This study investigates some of the benefits and drawbacks of assimilating terrestrial water storage (TWS) observations from the Gravity Recovery and Climate Experiment (GRACE) into a land surface model over India. GRACE observes TWS depletion associated with anthropogenic groundwater extraction in...
| Main Authors: | , , , , , , |
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| Format: | Journal Article |
| Published: |
American Geophysical Union
2017
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| Online Access: | http://hdl.handle.net/20.500.11937/68248 |
| _version_ | 1848761782763520000 |
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| author | Girotto, M. De Lannoy, G. Reichle, R. Rodell, M. Draper, C. Bhanja, S. Mukherjee, Abhijit |
| author_facet | Girotto, M. De Lannoy, G. Reichle, R. Rodell, M. Draper, C. Bhanja, S. Mukherjee, Abhijit |
| author_sort | Girotto, M. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | This study investigates some of the benefits and drawbacks of assimilating terrestrial water storage (TWS) observations from the Gravity Recovery and Climate Experiment (GRACE) into a land surface model over India. GRACE observes TWS depletion associated with anthropogenic groundwater extraction in northwest India. The model, however, does not represent anthropogenic groundwater withdrawals and is not skillful in reproducing the interannual variability of groundwater. Assimilation of GRACE TWS introduces long-term trends and improves the interannual variability in groundwater. But the assimilation also introduces a negative trend in simulated evapotranspiration, whereas in reality evapotranspiration is likely enhanced by irrigation, which is also unmodeled. Moreover, in situ measurements of shallow groundwater show no trend, suggesting that the trends are erroneously introduced by the assimilation into the modeled shallow groundwater, when in reality the groundwater is depleted in deeper aquifers. The results emphasize the importance of representing anthropogenic processes in land surface modeling and data assimilation systems. |
| first_indexed | 2025-11-14T10:37:09Z |
| format | Journal Article |
| id | curtin-20.500.11937-68248 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T10:37:09Z |
| publishDate | 2017 |
| publisher | American Geophysical Union |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-682482018-10-01T03:45:04Z Benefits and pitfalls of GRACE data assimilation: A case study of terrestrial water storage depletion in India Girotto, M. De Lannoy, G. Reichle, R. Rodell, M. Draper, C. Bhanja, S. Mukherjee, Abhijit This study investigates some of the benefits and drawbacks of assimilating terrestrial water storage (TWS) observations from the Gravity Recovery and Climate Experiment (GRACE) into a land surface model over India. GRACE observes TWS depletion associated with anthropogenic groundwater extraction in northwest India. The model, however, does not represent anthropogenic groundwater withdrawals and is not skillful in reproducing the interannual variability of groundwater. Assimilation of GRACE TWS introduces long-term trends and improves the interannual variability in groundwater. But the assimilation also introduces a negative trend in simulated evapotranspiration, whereas in reality evapotranspiration is likely enhanced by irrigation, which is also unmodeled. Moreover, in situ measurements of shallow groundwater show no trend, suggesting that the trends are erroneously introduced by the assimilation into the modeled shallow groundwater, when in reality the groundwater is depleted in deeper aquifers. The results emphasize the importance of representing anthropogenic processes in land surface modeling and data assimilation systems. 2017 Journal Article http://hdl.handle.net/20.500.11937/68248 10.1002/2017GL072994 American Geophysical Union fulltext |
| spellingShingle | Girotto, M. De Lannoy, G. Reichle, R. Rodell, M. Draper, C. Bhanja, S. Mukherjee, Abhijit Benefits and pitfalls of GRACE data assimilation: A case study of terrestrial water storage depletion in India |
| title | Benefits and pitfalls of GRACE data assimilation: A case study of terrestrial water storage depletion in India |
| title_full | Benefits and pitfalls of GRACE data assimilation: A case study of terrestrial water storage depletion in India |
| title_fullStr | Benefits and pitfalls of GRACE data assimilation: A case study of terrestrial water storage depletion in India |
| title_full_unstemmed | Benefits and pitfalls of GRACE data assimilation: A case study of terrestrial water storage depletion in India |
| title_short | Benefits and pitfalls of GRACE data assimilation: A case study of terrestrial water storage depletion in India |
| title_sort | benefits and pitfalls of grace data assimilation: a case study of terrestrial water storage depletion in india |
| url | http://hdl.handle.net/20.500.11937/68248 |