Lagrangian Data Assimilation for Improving Model Estimates of Velocity Fields and Residual Currents in a Tidal Estuary
Numerical models are associated with uncertainties that can be reduced through data assimilation (DA). Lower costs have driven a recent tendency to use Lagrangian instruments such as drifters and floats to obtain information about water bodies. However, difficulties emerge in their assimilation, sin...
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| Format: | Article |
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MDPI AG
2021-11-01
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| Series: | Applied Sciences |
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| Online Access: | https://www.mdpi.com/2076-3417/11/22/11006 |
| _version_ | 1797511268205068288 |
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| author | Neda Mardani Mohammadreza Khanarmuei Kabir Suara Richard Brown Adrian McCallum Roy C. Sidle |
| author_facet | Neda Mardani Mohammadreza Khanarmuei Kabir Suara Richard Brown Adrian McCallum Roy C. Sidle |
| author_sort | Neda Mardani |
| collection | DOAJ |
| description | Numerical models are associated with uncertainties that can be reduced through data assimilation (DA). Lower costs have driven a recent tendency to use Lagrangian instruments such as drifters and floats to obtain information about water bodies. However, difficulties emerge in their assimilation, since Lagrangian data are set out in a moving frame of reference and are not compatible with the fixed grid locations used in models to predict flow variables. We applied a pseudo-Lagrangian approach using OpenDA, an open-source DA tool to assimilate Lagrangian drifter data into an estuarine hydrodynamic model. Despite inherent challenges with using drifter datasets, the work showed that low-cost, low-resolution drifters can provide a relatively higher improvement over the Eulerian dataset due to the larger area coverage of the drifter. We showed that the assimilation of Lagrangian data obtained from GPS-tracked drifters in a tidal channel for a few hours can significantly improve modelled velocity fields (up to 30% herein). A 40% improvement in residual current direction was obtained when assimilating both Lagrangian and Eulerian data. We conclude that the best results are achieved when both Lagrangian and Eulerian datasets are assimilated into the hydrodynamic model. |
| first_indexed | 2024-03-10T05:42:58Z |
| format | Article |
| id | doaj.art-1e4cd5c065684d23941424d654c940f6 |
| institution | Directory Open Access Journal |
| issn | 2076-3417 |
| language | English |
| last_indexed | 2024-03-10T05:42:58Z |
| publishDate | 2021-11-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Applied Sciences |
| spelling | doaj.art-1e4cd5c065684d23941424d654c940f62023-11-22T22:22:13ZengMDPI AGApplied Sciences2076-34172021-11-0111221100610.3390/app112211006Lagrangian Data Assimilation for Improving Model Estimates of Velocity Fields and Residual Currents in a Tidal EstuaryNeda Mardani0Mohammadreza Khanarmuei1Kabir Suara2Richard Brown3Adrian McCallum4Roy C. Sidle5Civil and Environmental Engineering, University of the Sunshine Coast, Sunshine Coast, QLD 4556, AustraliaEnvironmental Fluid Mechanics Group, Queensland University of Technology, Brisbane, QLD 4000, AustraliaEnvironmental Fluid Mechanics Group, Queensland University of Technology, Brisbane, QLD 4000, AustraliaEnvironmental Fluid Mechanics Group, Queensland University of Technology, Brisbane, QLD 4000, AustraliaCivil and Environmental Engineering, University of the Sunshine Coast, Sunshine Coast, QLD 4556, AustraliaSustainability Research Centre, University of the Sunshine Coast, Sunshine Coast, QLD 4556, AustraliaNumerical models are associated with uncertainties that can be reduced through data assimilation (DA). Lower costs have driven a recent tendency to use Lagrangian instruments such as drifters and floats to obtain information about water bodies. However, difficulties emerge in their assimilation, since Lagrangian data are set out in a moving frame of reference and are not compatible with the fixed grid locations used in models to predict flow variables. We applied a pseudo-Lagrangian approach using OpenDA, an open-source DA tool to assimilate Lagrangian drifter data into an estuarine hydrodynamic model. Despite inherent challenges with using drifter datasets, the work showed that low-cost, low-resolution drifters can provide a relatively higher improvement over the Eulerian dataset due to the larger area coverage of the drifter. We showed that the assimilation of Lagrangian data obtained from GPS-tracked drifters in a tidal channel for a few hours can significantly improve modelled velocity fields (up to 30% herein). A 40% improvement in residual current direction was obtained when assimilating both Lagrangian and Eulerian data. We conclude that the best results are achieved when both Lagrangian and Eulerian datasets are assimilated into the hydrodynamic model.https://www.mdpi.com/2076-3417/11/22/11006estuaryhydrodynamic modelLagrangian assimilationEulerian assimilationresidual currentsOpenDA |
| spellingShingle | Neda Mardani Mohammadreza Khanarmuei Kabir Suara Richard Brown Adrian McCallum Roy C. Sidle Lagrangian Data Assimilation for Improving Model Estimates of Velocity Fields and Residual Currents in a Tidal Estuary Applied Sciences estuary hydrodynamic model Lagrangian assimilation Eulerian assimilation residual currents OpenDA |
| title | Lagrangian Data Assimilation for Improving Model Estimates of Velocity Fields and Residual Currents in a Tidal Estuary |
| title_full | Lagrangian Data Assimilation for Improving Model Estimates of Velocity Fields and Residual Currents in a Tidal Estuary |
| title_fullStr | Lagrangian Data Assimilation for Improving Model Estimates of Velocity Fields and Residual Currents in a Tidal Estuary |
| title_full_unstemmed | Lagrangian Data Assimilation for Improving Model Estimates of Velocity Fields and Residual Currents in a Tidal Estuary |
| title_short | Lagrangian Data Assimilation for Improving Model Estimates of Velocity Fields and Residual Currents in a Tidal Estuary |
| title_sort | lagrangian data assimilation for improving model estimates of velocity fields and residual currents in a tidal estuary |
| topic | estuary hydrodynamic model Lagrangian assimilation Eulerian assimilation residual currents OpenDA |
| url | https://www.mdpi.com/2076-3417/11/22/11006 |
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