The Impact of Air-Sea Flux Parameterization Methods on Simulating Storm Surges and Ocean Surface Currents

As the primary driver of energy transfer between atmospheric and oceanic systems, the air-sea momentum flux fundamentally governs coupled model dynamics through its regulation of wind stress partitioning. Given the complexity of the physical processes involved, simplified representations of these interactions are widely adopted to balance computational efficiency and physical fidelity. This systematic evaluation of five wind stress parameterizations reveals scheme-dependent variability in momentum partitioning efficiency, particularly under typhoon conditions. Our results quantify how the wind stress drag coefficient's formulation alters atmosphere-ocean feedback, with wave-state aware schemes exhibiting superior surge prediction accuracy compared to wind-speed-dependent approaches. Specifically, a larger wind stress drag coefficient leads to increased atmospheric bottom stress and sea surface stress, resulting in weaker winds and larger sea surface currents and storm surges. These findings provide actionable guidelines into the performance and sensitivity of various air-sea coupled models and offer useful suggestions for improving operational marine forecasting systems.