ExtremeWave Simulation due to Typhoon Bolaven based on locally Enhanced Fine-Mesh Unstructured Grid Model

Abstract

The performance of an integrally coupled wave-tide-surge model using the unstructured mesh system has beentested for the typhoon Bolaven which is regarded as the most powerful storm to strike the Korean Peninsula innearly a decade with wind gusts measured up to 50 m/s, causing serious damages with 19 victims. Use of theunstructured mesh in coastal sea regions of marginal scale allows all energy from deep to shallow waters to beseamlessly followed the physics of wave-circulation interactions can be then correctly resolved. The model coversthe whole Yellow and East China Seas with locally refined meshes near the regions of Gageo Island (offshoresouthwestern corner of the Korean Peninsula) and south of Jeju Island (Gangjeong and Seogwipo ports). Thewind and pressure fields during the passage of typhoon Bolaven are generated by the blending method. Generallythe numerical atmospheric model cannot satisfactorily reproduce the strength of typhoons due to dynamic andresolution restrictions. In this study we could achieve an improved conservation of the typhoon strength by blendingthe Holland typhoon model result by the empirical formula onto the ambient meteorological fields of NCEP dataset.The model results are compared with the observations and the model performance is then evaluated. The computedwave spectrums for one and two dimensions are compared with the observation in Ieodo station. Results swind gusts measured up to 50 m/s, causing serious damages with 19 victims. Use of theunstructured mesh in coastal sea regions of marginal scale allows all energy from deep to shallow waters to beseamlessly followed the physics of wave-circulation interactions can be then correctly resolved. The model coversthe whole Yellow and East China Seas with locally refined meshes near the regions of Gageo Island (offshoresouthwestern corner of the Korean Peninsula) and south of Jeju Island (Gangjeong and Seogwipo ports). Thewind and pressure fields during the passage of typhoon Bolaven are generated by the blending method. Generallythe numerical atmospheric model cannot satisfactorily reproduce the strength of typhoons due to dynamic andresolution restrictions. In this study we could achieve an improved conservation of the typhoon strength by blendingthe Holland typhoon model result by the empirical formula onto the ambient meteorological fields of NCEP dataset.The model results are compared with the observations and the model performance is then evaluated. The computedwave spectrums for one and two dimensions are compared with the observation in Ieodo station. Results s