Simulation Of Typhoon Process Using Coupled Atmosphere-Ocean-Wave Model Based On Satellite Data Assimilation

The determination of design parameters in marine environment has an essential influence on both the safety and economy of ocean structures.For the typhoon-prone areas,in order to obtain the design parameter,it is very significant to simulate accurate wind field,wave field and current field.On the basis of Model Coupling Toolkit(MCT),the mesoscale atmosphere model WRF,the ocean model FVCOM and the third-generation wave model SWAN are coupled.Furthermore,the data assimilation of wind field is applied by assimilation module WRFDA of WRF,and a real-time coupling numerical model with dada assimilation(WRF-FVCOM-SWAN-ASSIMILATION,W-F-S-A)is developed.The typhoon process affecting Hainan Island are simulated using the coupling numerical model W-F-S-A.Furthermore,the design parameters are obtained from the simulation results.The main contents of this thesis are as follows.(1)On the basis of model coupling of WRF-FVCOM-SWAN throuh MCT,a real-time coupling and assimilation model of W-F-S-A is established successfully using the hotstart mode of FVCOM and SWAN.(2)The numerical results of path and intensity of wind field,sea surface temperature field and wave field were compared through pure WRF model,pure coupled model and coupled assimilation model W-F-S-A.The results show that the simulation results of W-F-S-A model are in best agreement with the measured data.(3)The numerical results of wind field,current field,SST field and wave field of a series of 70 typhoons which affected Hainan Island from 1999 to 2018 are simulated by the coupled assimilation model W-F-S-A.(4)According to the simulated results,the various return period parameters are calculated for the wind and wave by the traditional design standards and joint probability distribution respectively.