Abstract:
Existing engineering empirical models for typhoon wind fields are corrected based on limited measured data and does not take the real-time coupling between the ocean movements (e.g. wave and ocean current) and the horizontal wind speed into account. To explore the influence of ocean movement on the whole typhoon landing process, an atmosphere-sea-wave (W-S-F) real-time coupling simulation platform was developed based on the MCT coupler by integrating the mesoscale WRF atmospheric model, the third generation of shallow sea wave SWAN model, and the three-dimensional hydrodynamic FVCOM model. On this basis, the spatial and temporal evolutions of marine environment throughout the whole landing process of typhoon “Meranti” were simulated. Next, differences between the W-S-F coupling platform and the decoupled WRF model throughout the typhoon landing process were analyzed regarding the pneumatic structure, vertical wind shear, heat flux, and friction velocity. Finally, effects of the ocean movement on horizontal wind speed characteristics and action mechanism were extracted. Results demonstrate that the proposed W-S-F coupling platform can simulate the wind field throughout the typhoon landing process with considerations of the ocean movement. At low-altitude spaces, ocean movement can promote typhoon horizontal wind speed, but this influence diminishes gradually with the increase of height. However, at high-altitude spaces, ocean movement inhibits the typhoon horizontal wind speed and such consumption is strengthened as a function of height.