| In recent years,marine disasters(tsunamis,typhoon waves,storm surges,etc.)occured frequently due to the impact of global climate change.The extreme waves and storm surge caused by typhoon will pose a major threat to the safety of offshore engineering facilities and coastal cities.It is of great significance to study typhoon waves and storm surges for disaster prevention and mitigation in coastal cities,the accurate typhoon path and intensity are important prerequisites for ensuring accurate study of changes in the marine water environment caused by typhoons.Only by revisiting the temporal and spatial changes of various parameters when the typhoon occurs as accurately as possible,can we accurately study the temporal and spatial distribution characteristics and evolution laws of typhoon waves and storm surges,thus providing more scientific suggestions for marine disaster prevention and mitigation.Previous studies have shown that coastal vegetation can effectively reduce the impact of typhoon waves and storm surges caused by typhoons.Therefore,it is very important to study the impact of coastal vegetation on the hydrodynamic environment,especially in the extreme weather,which is of great significance to prevent marine disasters,promote marine economic development and ecological environment.This paper studies the coastal typhoon waves and wind waves in currents in coastal vegetation zones based on SWAN model and ECOMSED model.The main contents and results are as follows:(1)Taking Typhoon Kai-tak as an example,the accuracy of ERA and CCMP reanalysis wind fields is analyzed and compared by using SWAN model.The results show that the quality of the CCMP wind field at the measuring point is better than that of the ERA wind field.The two wind fields are smaller when the wind speed is large.To compensate for this shortcoming,this paper proposes a correction formula for the reanalysis wind field of a single typhoon.The verification of the measured data shows that the accuracy of the wind field after the correction of the method is greatly improved,and the simulated typhoon waves are closer to the measured values.(2)Taking the three typhoons in 2015 and 2016 as examples,the accuracy of ERA,CCMP and CFSv2 reanalysis wind fields is studied by using SWAN model.The results show that the quality of CCMP wind field is better on the whole,CFSv2 quality is in the middle,ERA wind field and CCMP wind field near the typhoon center are smaller obviously.In order to correct the wind speed and path of reanalysis wind fields near the typhoon center,this paper proposes a revised formula for the mixed wind field of three typhoons.At the same time,the applicability of the blended wind field is verified by the buoy and satellite observation data,and the simulation accuracy of the typhoon wave when the three typhoons coexist is simulated.(3)Taking Liao River Estuary wetland as the research area,based on the verification of tidal current model,the accuracy of dynamic boundary and vegetation module added in ECOMSED model is verified.Then,on the basis of verification of SWAN wind wave and vegetation module,the numerical model of wind,wave,current and vegetation coupling in Liao River Estuary Wetland was established by coupling SWAN model with ECOMSED model.The effects of vegetation on wave and current propagation in Liao River Estuary Wetland under the influence of a tropical cyclone in 1997 were studied.The results show that due to the influence of vegetation resistance,the velocity of water flow in vegetation waters decreases,the maximum value decreases by nearly 50%.The existence of vegetation delays the flooding time,but the water flow may temporarily backwater in vegetation areas and delay the time of dew beach.Due to vegetation dissipation,the wave height attenuation in vegetation areas is more obvious than that in other waters.The study shows that the higher the incident wave height is,the more obvious the attenuation of wave height in vegetation waters is. |
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