A hybrid framework for rapidly locating transition zones: A comparison of event‐ and response‐based return water levels in the Suwannee River FL
Jane, R. A.; Malagon Santos, V.; Rashid, M.M.; Doebele, L.; Wahl, T.; Timmers, S.R.; Serafin, K.A.; Schmied, L.; Lindemer, C. (2022). A hybrid framework for rapidly locating transition zones: A comparison of event‐ and response‐based return water levels in the Suwannee River FL. Water Resour. Res. 58(11): e2022WR032481. https://dx.doi.org/10.1029/2022wr032481
In: Water Resources Research: a Journal of the Sciences of Water. American Geophysical Union: Washington etc.. ISSN 0043-1397; e-ISSN 1944-7973, more
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| Authors | | Top |
- Jane, R. A.
- Malagon Santos, V., more
- Rashid, M.M.
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- Doebele, L.
- Wahl, T.
- Timmers, S.R.
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- Serafin, K.A.
- Schmied, L.
- Lindemer, C.
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| Abstract |
Flood risk assessments commonly use event-based approaches to reduce the number of scenarios required to be run through computationally intensive physical process models. Often the return period of the response variable (e.g., a fluvial water level or overtopping discharge) generated by an event (e.g., upstream/downstream water level or set of sea state variables) does not match that of the event itself; a limitation of event-based approaches which can lead to the misspecification of flood risk. We present a transferable hybrid statistical-hydraulic modeling framework for rapidly locating transition zones; river reaches where extreme water levels are driven by both upstream riverine discharge and downstream sea level. Instead of an event-based approach the framework utilizes a surrogate model to reduce computational expense of the hydraulic model. The surrogate-based approach allows the empirical estimation of response-based along-river return levels from a large number of plausible discharge–coastal still water level events simulated from the statistical model. We assess the robustness of the event-based approach by comparing the associated return levels with the response-based return levels. The framework is applied to the Suwannee River in Florida (United States). Three surrogate models are evaluated, highlighting the enhanced ability of non-linear models to accurately capture discharge-sea level interactions along the river. The along-river return levels of the “most-likely” design event are found to lie within the range of variability of the response-based return levels for most of the transition zone. |
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