Predicting typhoon-induced storm surge tide with a two-dimensional hydrodynamic model and artificial neural network model

W.-B Chen,W.-C Liu,M.-H Hsu

doi:10.5194/nhess-12-3799-2012

Abstract

Abstract. Precise predictions of storm surges during typhoon events have the necessity for disaster prevention in coastal seas. This paper explores an artificial neural network (ANN) model, including the back propagation neural network (BPNN) and adaptive neuro-fuzzy inference system (ANFIS) algorithms used to correct poor calculations with a two-dimensional hydrodynamic model in predicting storm surge height during typhoon events. The two-dimensional model has a fine horizontal resolution and considers the interaction between storm surges and astronomical tides, which can be applied for describing the complicated physical properties of storm surges along the east coast of Taiwan. The model is driven by the tidal elevation at the open boundaries using a global ocean tidal model and is forced by the meteorological conditions using a cyclone model. The simulated results of the hydrodynamic model indicate that this model fails to predict storm surge height during the model calibration and verification phases as typhoons approached the east coast of Taiwan. The BPNN model can reproduce the astronomical tide level but fails to modify the prediction of the storm surge tide level. The ANFIS model satisfactorily predicts both the astronomical tide level and the storm surge height during the training and verification phases and exhibits the lowest values of mean absolute error and root-mean-square error compared to the simulated results at the different stations using the hydrodynamic model and the BPNN model. Comparison results showed that the ANFIS techniques could be successfully applied in predicting water levels along the east coastal of Taiwan during typhoon events.

Highlights

Storm surges are as a result of strong tropical storms called typhoons in the northwestern Pacific Ocean
The country is often subjected to severe sea states that are induced by typhoons and occur during the summer and winter seasons in either the South China Sea or the northwest Pacific Ocean near the Philippines, which result in the extensive loss of life and property
The results indicate that the peak error (PE), mean absolute error (MAE), and root-meansquare error (RMSE) values at Suao Port and Hualien Port are less than those at Chenggong Fish Port

Summary

Introduction

Storm surges are as a result of strong tropical storms called typhoons in the northwestern Pacific Ocean. Abnormal sea level rise due to storm surge is caused by strong winds and atmospheric pressure disturbances (You and Seo, 2009). The country is often subjected to severe sea states that are induced by typhoons and occur during the summer and winter seasons in either the South China Sea or the northwest Pacific Ocean near the Philippines, which result in the extensive loss of life and property. As a typhoon approaches Taiwan, its strong wind and low atmospheric pressure often cause storm surges that can result in severe damage to coastal areas, especially on the low-lying lands near river mouths because of the double effects of the river floods by typhoonbrought rains and backward uplifting seawater floods from storm surges. It is necessary to develop a reliable model to predict the height of typhoon-induced storm surge for coastal management and hazard mitigation

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Methods

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Conclusion