Simultaneous perturbation stochastic approximation for tidal models

The Dutch continental shelf model (DCSM) is a shallow sea model of entire continental shelf which is used operationally in the Netherlands to forecast the storm surges in the North Sea. The forecasts are necessary to support the decision of the timely closure of the moveable storm surge barriers to protect the land. In this study, an automated model calibration method, simultaneous perturbation stochastic approximation (SPSA) is implemented for tidal calibration of the DCSM. The method uses objective function evaluations to obtain the gradient approximations. The gradient approximation for the... Mehr ...

Verfasser: Altaf, M.U.
Heemink, A.W.
Verlaan, M.
Hoteit, Ibrahim
Dokumenttyp: Artikel
Erscheinungsdatum: 2011
Verlag/Hrsg.: Springer Nature
Schlagwörter: Numerical tidal modeling / Parameter estimation / Simultaneous perturbation / Stochastic approximation / Calibration method / Calibration parameters / Central difference method / Computational costs / Continental shelves / Gradient approximation / Model calibration / Netherlands / North Sea / Proper Orthogonal / Shallow sea / Simultaneous perturbation stochastic approximation / Stochastic approximations / Storm surges / Tidal models / Approximation theory / Calibration / Cost benefit analysis / Floods / Function evaluation / Perturbation techniques / Stochastic models / Stochastic systems / Storms / Steepest descent method / accuracy assessment / algorithm / bathymetry / continental shelf / cost-benefit analysis / numerical model / optimization / parameterization / perturbation / shallow water / stochasticity / storm surge / tidal cycle / tidal modeling / weather forecasting / Atlantic Ocean
Sprache: Englisch
Permalink: https://search.fid-benelux.de/Record/base-26808803
Datenquelle: BASE; Originalkatalog
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Link(s) : http://hdl.handle.net/10754/334621

The Dutch continental shelf model (DCSM) is a shallow sea model of entire continental shelf which is used operationally in the Netherlands to forecast the storm surges in the North Sea. The forecasts are necessary to support the decision of the timely closure of the moveable storm surge barriers to protect the land. In this study, an automated model calibration method, simultaneous perturbation stochastic approximation (SPSA) is implemented for tidal calibration of the DCSM. The method uses objective function evaluations to obtain the gradient approximations. The gradient approximation for the central difference method uses only two objective function evaluation independent of the number of parameters being optimized. The calibration parameter in this study is the model bathymetry. A number of calibration experiments is performed. The effectiveness of the algorithm is evaluated in terms of the accuracy of the final results as well as the computational costs required to produce these results. In doing so, comparison is made with a traditional steepest descent method and also with a newly developed proper orthogonal decompositionbased calibration method. The main findings are: (1) The SPSA method gives comparable results to steepest descent method with little computational cost. (2) The SPSA method with little computational cost can be used to estimate large number of parameters.