1D and 2D Hydrodynamic Modeling of Riverine-Estuary System under Extreme Storms: A Case Study of Delaware Bay/River Basin
Abstract
Flooding events due to extreme weather patterns and climate change in low-lying coastal regions are increasingly important problems and a growing social issue. The existing hydraulic routing strategies within the National Water Model (NWM) for total water level forecasts are inadequate in these regions. Thus, development of new innovations in the NWM is now of utmost importance to meet the 'summit-to-sea' requirements in these regions. For several decades, simplified river models have been used to forecast water levels on major rivers. However, in coastal zones where rivers broaden and flow into bays, the current modeling assumptions in the NWM become a limiting factor. A more comprehensive modeling approach is required to understand the complex hydrodynamics in areas such as the Delaware River and Bay region. Therefore, we used a modeling framework that combines the ocean model, the wave model, the hydrologic model and the hydrodynamic model. In this regard, we examined the fidelity of different open-sourced 1D/2D hydrodynamic models in the Delaware River and Bay. Practical implications of either 1D or 2D or coupled 1D/2D modeling approaches/tools were analyzed, namely: (i) a well-calibrated 1D dynamic wave solver - HEC-RAS model (USACE, 2016); (ii) the 1D NWM diffusive wave (Muskingum-Cunge, MC) hydraulic routing approach; (iii) the 2D Advanced Circulation Ocean Model (ADCIRC); and (iv) 1D/2D D-Flow FM. A key element is that all the four hydrodynamic models use similar geometric data representation and roughness information. Three different tropical storms (i.e., Hurricanes Irene, Isabel and Super Storm Sandy) were considered in order to understand the model performance in the Delaware Bay/River region. This study demonstrates that a coupled 1D/2D D-Flow modeling framework is more accurate and efficient in simulating water levels for practical applications. The relative performance of each model framework will be discussed, quantified using several model assessment metrics, and visualized through diagrams.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2018
- Bibcode:
- 2018AGUFM.H41P2345M
- Keywords:
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- 3355 Regional modeling;
- ATMOSPHERIC PROCESSESDE: 1803 Anthropogenic effects;
- HYDROLOGYDE: 1805 Computational hydrology;
- HYDROLOGYDE: 1902 Community modeling frameworks;
- INFORMATICS