Estimation of the Manning’s n coefficient in multi-constituent tidal models by assimilating satellite observations with the adjoint data assimilation
The bottom friction is critical for the dissipation of the global tidal energy. The bottom friction coefficient is traditionally determined using the Manning’s n formulation in tidal models. The Manning’s n coefficient in the Manning’s n formulation is vital for the accurate simulation and predictio...
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Frontiers Media S.A.
2023-03-01
|
| Series: | Frontiers in Marine Science |
| Subjects: | |
| Online Access: | https://www.frontiersin.org/articles/10.3389/fmars.2023.1151951/full |
| _version_ | 1797857839002157056 |
|---|---|
| author | Daosheng Wang Daosheng Wang Daosheng Wang Jinglu Jiang Zilu Wei Jun Cheng Jicai Zhang |
| author_facet | Daosheng Wang Daosheng Wang Daosheng Wang Jinglu Jiang Zilu Wei Jun Cheng Jicai Zhang |
| author_sort | Daosheng Wang |
| collection | DOAJ |
| description | The bottom friction is critical for the dissipation of the global tidal energy. The bottom friction coefficient is traditionally determined using the Manning’s n formulation in tidal models. The Manning’s n coefficient in the Manning’s n formulation is vital for the accurate simulation and prediction of the tide in coastal shallow waters, but it cannot be directly measured and contains large amounts of uncertainties. Based on a two-dimensional multi-constituent tidal model with the adjoint data assimilation, the estimation of the Manning’s n coefficient is investigated by assimilating satellite observations in the Bohai, Yellow and East China Seas with the simulation of four principal tidal constituents M2, S2, K1 and O1. In the twin experiments, the Manning’s n coefficient is assumed to be constant, and it is estimated by assimilating the synthetic observations at the spatial locations of the satellite tracks. Regardless the inclusion of artificial random observational errors associated with synthetic observations, the model performance is improved as evaluated by the independent synthetic observations. The prescribed ‘real’ Manning’s n coefficient is reasonably estimated, indicating that the adjoint data assimilation is an effective method to estimate the Manning’s n coefficient in multi-constituent tidal models. In the practical experiments, the errors between the independent observations at the tidal gauge stations and the corresponding simulated results of the four principal tidal constituents are substantially decreased under both scenarios of the constant and spatially-temporally varying Manning’s n coefficient estimated by assimilating the satellite observations with the adjoint data assimilation. In addition, the estimated spatial and temporal variation trend is robust and not affected by the model settings. The spatially-temporally varying Manning’s n coefficient is negatively correlated with the current speed and shows significant spatial variation in the shallow water areas. This study demonstrates that the Manning’s n coefficient can be reasonably estimated by the adjoint data assimilation, which allows significant improvement in accurate simulation of the ocean tide. |
| first_indexed | 2024-04-09T21:04:19Z |
| format | Article |
| id | doaj.art-a1fe0625aa36489ab4142209f01494e5 |
| institution | Directory Open Access Journal |
| issn | 2296-7745 |
| language | English |
| last_indexed | 2024-04-09T21:04:19Z |
| publishDate | 2023-03-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Marine Science |
| spelling | doaj.art-a1fe0625aa36489ab4142209f01494e52023-03-29T05:27:20ZengFrontiers Media S.A.Frontiers in Marine Science2296-77452023-03-011010.3389/fmars.2023.11519511151951Estimation of the Manning’s n coefficient in multi-constituent tidal models by assimilating satellite observations with the adjoint data assimilationDaosheng Wang0Daosheng Wang1Daosheng Wang2Jinglu Jiang3Zilu Wei4Jun Cheng5Jicai Zhang6Hubei Key Laboratory of Marine Geological Resources, College of Marine Science and Technology, China University of Geosciences, Wuhan, ChinaKey Laboratory of Marine Environmental Survey Technology and Application, Ministry of Natural Resources, Guangzhou, ChinaShenzhen Research Institute, China University of Geosciences, Shenzhen, ChinaInstitute for Advanced Studies in Finance and Economics, Hubei University of Economics, Wuhan, ChinaInstitute of Physical Oceanography and Remote Sensing, Ocean College, Zhejiang University, Zhoushan, ChinaDepartment of Environmental and Sustainability Sciences, Kean University, Union, NJ, United StatesState Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai, ChinaThe bottom friction is critical for the dissipation of the global tidal energy. The bottom friction coefficient is traditionally determined using the Manning’s n formulation in tidal models. The Manning’s n coefficient in the Manning’s n formulation is vital for the accurate simulation and prediction of the tide in coastal shallow waters, but it cannot be directly measured and contains large amounts of uncertainties. Based on a two-dimensional multi-constituent tidal model with the adjoint data assimilation, the estimation of the Manning’s n coefficient is investigated by assimilating satellite observations in the Bohai, Yellow and East China Seas with the simulation of four principal tidal constituents M2, S2, K1 and O1. In the twin experiments, the Manning’s n coefficient is assumed to be constant, and it is estimated by assimilating the synthetic observations at the spatial locations of the satellite tracks. Regardless the inclusion of artificial random observational errors associated with synthetic observations, the model performance is improved as evaluated by the independent synthetic observations. The prescribed ‘real’ Manning’s n coefficient is reasonably estimated, indicating that the adjoint data assimilation is an effective method to estimate the Manning’s n coefficient in multi-constituent tidal models. In the practical experiments, the errors between the independent observations at the tidal gauge stations and the corresponding simulated results of the four principal tidal constituents are substantially decreased under both scenarios of the constant and spatially-temporally varying Manning’s n coefficient estimated by assimilating the satellite observations with the adjoint data assimilation. In addition, the estimated spatial and temporal variation trend is robust and not affected by the model settings. The spatially-temporally varying Manning’s n coefficient is negatively correlated with the current speed and shows significant spatial variation in the shallow water areas. This study demonstrates that the Manning’s n coefficient can be reasonably estimated by the adjoint data assimilation, which allows significant improvement in accurate simulation of the ocean tide.https://www.frontiersin.org/articles/10.3389/fmars.2023.1151951/fullManning’s n coefficientbottom friction coefficientadjoint data assimilationparameter estimationspatial-temporal variation |
| spellingShingle | Daosheng Wang Daosheng Wang Daosheng Wang Jinglu Jiang Zilu Wei Jun Cheng Jicai Zhang Estimation of the Manning’s n coefficient in multi-constituent tidal models by assimilating satellite observations with the adjoint data assimilation Frontiers in Marine Science Manning’s n coefficient bottom friction coefficient adjoint data assimilation parameter estimation spatial-temporal variation |
| title | Estimation of the Manning’s n coefficient in multi-constituent tidal models by assimilating satellite observations with the adjoint data assimilation |
| title_full | Estimation of the Manning’s n coefficient in multi-constituent tidal models by assimilating satellite observations with the adjoint data assimilation |
| title_fullStr | Estimation of the Manning’s n coefficient in multi-constituent tidal models by assimilating satellite observations with the adjoint data assimilation |
| title_full_unstemmed | Estimation of the Manning’s n coefficient in multi-constituent tidal models by assimilating satellite observations with the adjoint data assimilation |
| title_short | Estimation of the Manning’s n coefficient in multi-constituent tidal models by assimilating satellite observations with the adjoint data assimilation |
| title_sort | estimation of the manning s n coefficient in multi constituent tidal models by assimilating satellite observations with the adjoint data assimilation |
| topic | Manning’s n coefficient bottom friction coefficient adjoint data assimilation parameter estimation spatial-temporal variation |
| url | https://www.frontiersin.org/articles/10.3389/fmars.2023.1151951/full |
| work_keys_str_mv | AT daoshengwang estimationofthemanningsncoefficientinmulticonstituenttidalmodelsbyassimilatingsatelliteobservationswiththeadjointdataassimilation AT daoshengwang estimationofthemanningsncoefficientinmulticonstituenttidalmodelsbyassimilatingsatelliteobservationswiththeadjointdataassimilation AT daoshengwang estimationofthemanningsncoefficientinmulticonstituenttidalmodelsbyassimilatingsatelliteobservationswiththeadjointdataassimilation AT jinglujiang estimationofthemanningsncoefficientinmulticonstituenttidalmodelsbyassimilatingsatelliteobservationswiththeadjointdataassimilation AT ziluwei estimationofthemanningsncoefficientinmulticonstituenttidalmodelsbyassimilatingsatelliteobservationswiththeadjointdataassimilation AT juncheng estimationofthemanningsncoefficientinmulticonstituenttidalmodelsbyassimilatingsatelliteobservationswiththeadjointdataassimilation AT jicaizhang estimationofthemanningsncoefficientinmulticonstituenttidalmodelsbyassimilatingsatelliteobservationswiththeadjointdataassimilation |