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Langmuir turbulence (LT) due to the Craik–Leibovich vortex force had a clear impact on the thermal response of the ocean mixed layer to Supertyphoon Haitang (2005) east of the Luzon Strait. This impact is investigated using a 3D wave–current coupled framework consisting of the Princeton Ocean Model with the generalized coordinate system (POMgcs) and the Simulating Waves Nearshore (SWAN) wave model. The Coriolis–Stokes forcing (CSF), the Craik–Leibovich vortex forcing (CLVF), and the second-moment closure model of LT developed by Harcourt are introduced into the circulation model. The coupled system is able to reproduce the upper-ocean temperature and surface mixed layer depth reasonably well during the forced stage of the supertyphoon. The typhoon-induced “cold suction” and “heat pump” processes are significantly affected by LT. Local LT mixing strengthened the sea surface cooling by more than 0.5°C in most typhoon-affected regions. Besides LT, Lagrangian advection of temperature also modulates the SST cooling, inducing a negative (positive) SST difference in the vicinity of the typhoon center (outside of the cooling region). In addition, CLVF has the same order of magnitude as the horizontal advection in the typhoon-induced strong-vorticity region. While the geostrophy is broken down during the forced stage of Haitang, CLVF can help establish and maintain typhoon-induced quasigeostrophy during and after the typhoon. Finally, the effect of LT on the countergradient turbulent flux under the supertyphoon is discussed.

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Strong winds lead to large amounts of sea spray in the lowest part of the atmospheric boundary layer. The spray droplets affect the air‐sea heat fluxes due to their evaporation and the momentum due to the change of sea surface, and in turn change the upper ocean thermal structure. In this study, impact of sea spray on upper ocean temperatures in the Yellow and East China Seas (YES) during typhoon Rammasun's passage is investigated using the POMgcs ocean model with a sea spray parameterization scheme, in which the sea spray‐induced heat fluxes are based on an improved Fairall's sea spray heat fluxes algorithm, and the sea spray‐induced momentum fluxes are derived from an improved COARE version 2.6 bulk model. The distribution of the sea spray mediated turbulent fluxes was primarily located at Rammasun eye‐wall region, in accord with the maximal wind speeds regions. When Rammasun enters the Yellow sea, the sea spray mediated latent (sensible) heat flux maximum is enhanced by 26% (13.5%) compared to that of the interfacial latent (sensible) heat flux. The maximum of the total air‐sea momentum fluxes is enhanced by 43% compared to the counterpart of the interfacial momentum flux. Furthermore, the sea spray plays a key role in enhancing the intensity of the typhoon‐induced “cold suction” and “heat pump” processes. When the effect of sea spray is considered, the maximum of the sea surface cooling in the right side of Rammasun's track is increased by 0.5°C, which is closer to the available satellite observations.

A coupled ocean-wave-sea spray model system is used to investigate the impacts of sea spray and sea surface roughness on the response of the upper ocean to the passage of the super typhoon Haitang. Sea spray mediated heat and momentum fluxes are derived from an improved version of Fairall’s heat fluxes formulation (Zhang et al., 2017) and Andreas’s sea spray-mediated momentum flux models. For winds ranging from low to extremely high speeds, a new parameterization scheme for the sea surface roughness is developed, in which the effects of wave state and sea spray are introduced. In this formulation, the drag coefficient has minimal values over the right quadrant of the typhoon track, along which the typhoon-generated waves are longer, smoother, and older, compared to other quadrants. Using traditional interfacial air-sea turbulent (sensible, latent, and momentum) fluxes, the sea surface cooling response to typhoon Haitang is overestimated by 1 °C, which can be compensated by the effects of sea spray and ocean waves on the right side of the storm. Inclusion of sea spray-mediated turbulent fluxes and sea surface roughness, modulated by ocean waves, gives enhanced cooling along the left edges of the cooling area by 0.2 °C, consistent with the upper ocean temperature observations.

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