A Coupled FVCOM-WRF Model: Applications for Hurricane and Typhoon Simulations

A fully-coupled atmospheric-ocean model was developed by implementing WRF into FVCOM through the Earth System Model Framework (ESMF). Coupling between FVCOM and WRF are designed for the multi-domain configurations for both atmospheric and ocean model components, and the data exchange between structured-grid WRF and unstructured-grid FVCOM are achieved through ESMF. The current version of FVCOM-WRF coupled system includes the surface wave-current interaction and can be run with options of either hydrostatic or non-hydrostatic dynamics for the ocean component. This model is applied for hurricanes in the Atlantic Ocean and typhoons in the Pacific Ocean, including the 2012 Hurricane Sandy, 2017 Typhoon Hato and 2018 Typhoon Mangkhut. The experiments were made for the cases with and without coupling. The model-data comparison results show that the storm’s intensity and pathway can be significantly improved with the ocean feedback in the WRF simulation, and in turn provided the better prediction of oceanic currents, mixing, and surface wave as well as storm surges in the FVCOM. These improvements demonstrated that importance of including the dynamics of ocean mixed layer and non-hydrostatic processes as well as current-wave interactions.