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Waves critically modulate the air‐sea fluxes, and upper‐ocean thermodynamics in a Tropical Cyclone (TC) system. This study improves the modeling of TC intensification by incorporating non‐breaking wave‐induced turbulence and sea spray from breaking waves into an atmosphere‐ocean‐wave coupled model. Notably, wind forecast error decreased by around 10% prior to TCs' peak intensity. The positive feedback of sea spray along with compensatory negative feedback from non‐breaking waves, overall enhanced TCs' intensity. These breaking and non‐breaking wave‐coupled processes consistently cool sea surface temperature, resulting in improvement of the modeled SST. Observed improvements in full‐year TC cases ranging from Categories I to IV in this study suggest that an accurate characterization of ocean wave‐coupled processes is crucial for improving TCs' intensity forecasts and advancing our understanding of severe weather events in both, the atmosphere and ocean. Plain Language Summary: Tropical Cyclones (TCs), such as hurricanes and typhoons, are destructive natural disasters that can cause extensive damage. Our study focused on understanding the role of ocean waves and related processes in TCs. Through numerical modeling, we found that ocean waves, specifically breaking and non‐breaking waves, have a substantial influence on TCs' intensity. Breaking waves contribute positively through the production of sea spray droplets, while non‐breaking wave‐induced turbulence has a compensatory negative effect, resulting in an enhancement in TCs' intensity. Incorporating both wave mechanisms into the models improved the accuracy of TCs' intensity and their underlying sea surface temperature. By highlighting the importance of ocean wave‐coupled physics, we aim to enhance our understanding of TCs and improve disaster preparedness to mitigate their impacts on coastal communities. Key Points: Full‐year regional hindcast of Tropical Cyclones (TCs) at the North West AustraliaInclusion of wave‐coupled processes improves TCs modeling, by reducing forecast errors and enhancing rapid intensification simulationsSea spray increases TC development while nonbreaking wave turbulence has the opposite effect with the first process dominating [ABSTRACT FROM AUTHOR]

The dissipation of wave energy in the marginal ice zone is often attributed to wave scattering and the dissipative mechanisms associated with the ice layer. In this study we present observations indicating that turbulence generated by the differential velocity between the sea ice cover and the orbital wave motion may be an important dissipative mechanism of wave energy. Through field measurements of under‐ice turbulence dissipation rates in pancake and frazil ice, it is shown that turbulence‐induced wave attenuation coefficients are in agreement with observed wave attenuation in the marginal ice zone. The results suggest that the turbulence‐induced attenuation rates can be parameterized by the characteristic wave properties and a coefficient. The coefficient is determined by the ice layer properties. Key Points: Turbulence may be an important dissipative mechanism of wave energy in the MIZTurbulence‐induced attenuation coefficient can be determined from measurements of wave energy and turbulence at a single locationTurbulence dissipation is parameterized through characteristic wave and ice properties [ABSTRACT FROM AUTHOR]

Tropical cyclones dissipate large amounts of energy into the upper ocean, locally enhancing vertical mixing and cooling the sea surface. In this study, we investigate how the response of the ocean to tropical cyclones is affected by additional mixing from unbroken surface waves. This ''Surface Wave Mixing'' (SWM) is represented by a novel parameterization, in which the wave orbital motion contributes directly to the production of turbulent kinetic energy. The parameterization is implemented here as a modification to the k-e turbulence scheme, used within an ocean model with 1/48 horizontal resolution (MOM5). This model is forced with idealized tropical cyclone wind fields based on observed case studies. Relative to simulations without SMW, the inclusion of SWM leads to surface temperature differences of around 0.58C near the storm track, typically with warm anomalies on the side with the strongest winds and cool anomalies in other regions. This pattern is explained by an initial wave-induced deepening of the mixed layer, which can modify the subsequent shear-induced entrainment and upwelling. The temperature anomalies from SWM could potentially influence tropical cyclone intensity and structure. [ABSTRACT FROM AUTHOR]

Wave-induced turbulence due to breaking in the absence of surface shear stresses is investigated experimentally. A high-fidelity particle image velocimetry (PIV) technique is used to measure the turbulence near the water surface, inside the wave crests. The spatial velocity vector fields of the breaking waves acquired from PIV provide accurate vertical velocity profiles near the air-water interface, as well as wavenumber velocity spectra beneath the breaking waves at different depths. These velocity spectra exhibit a Kolmogorov interval at high wavenumbers, indicating the presence of isotropic turbulence and permitting an estimation of energy dissipation rates. The depth dependence of dissipation rates of the breaking waves generated in the laboratory shows a scaling similar to that found in wind-forced breaking waves in the field. A phase dependence in the dissipation rates of turbulence kinetic energy is also observed, which should be considered to improve the accuracy of the estimated and modeled wave energy dissipation. [ABSTRACT FROM AUTHOR]

This paper studies the impact of the surface waves on the turbulent mixing. The satellite observations of suspended particulate matter (SPM) at the ocean surface as an indicator of turbulent quantities of the flow are used. In a water column, SPM builds a vertical profile depending on settling velocities of the particles and on vertical mixing processes; thus, SPM is a perfect marker to study the turbulent quantities of the flow. Satellite observations in the North Sea show that surface SPM concentrations, in locations of its deposition, grow rapidly and build plume-shaped, long (many kilometers) uninterrupted and consistent structures during a storm. Also, satellites reveal that SPM rapidly sinks to the seabed after the storm peak has passed and wave height decreases (i.e., in the absence of strong turbulence). The nonbreaking wave-induced turbulence has been discussed, parameterized, and implemented into an equation of evolution of turbulent kinetic energy (TKE) in the frame of mean-flow concept, which can be used in existing circulation models. The ratio between dissipated and total wave energy is used to describe the influence of wave damping on the mean flow. The numerical tests reproduce experiments in a wave tank very well and are supported by observations of SPM in the North Sea. Their results show that the motion of an individual nonbreaking wave includes turbulent fluctuations if the critical Reynolds number for wave motion is exceeded, independent of the presence of currents due to wind or tides. These fluctuations can produce high diffusivity and strongly influence mixing in the upper water layer of the ocean. [ABSTRACT FROM AUTHOR]

This paper is dedicated to wave-induced turbulence unrelated to wave breaking. The existence of such turbulence has been foreshadowed in a number of experimental, theoretical, and numerical studies. The current study presents direct measurements of this turbulence. The laboratory experiment was conducted by means of particle image velocimetry, which allowed estimates of wavenumber velocity spectra beneath monochromatic nonbreaking unforced waves. Observed spectra intermittently exhibited the Kolmogorov interval associated with the presence of isotropic turbulence. The magnitudes of the energy dissipation rates due to this turbulence in the particular case of 1.5-Hz deep-water waves were quantified as a function of the surface wave amplitude. The presence of such turbulence, previously not accounted for, can affect the physics of the wave energy dissipation, the subsurface boundary layer, and the ocean mixing in a significant way. [ABSTRACT FROM AUTHOR]

Abstract: Climate modelling, to a great extent, is based on simulating air–sea interactions at larger scales. Small-scale interactions and related phenomena, such as wind-generated waves and wave-induced turbulence are sub-grid processes for such models and therefore cannot be simulated explicitly. In the meantime, the waves play the principal role in the upper-ocean mixing. This role is usually parameterized, mostly to account for the wave-breaking turbulence and to describe downward diffusion of such turbulence. The main purpose of the paper is to demonstrate that an important physical mechanism, that is the ocean mixing due to waves, is presently missing in the climate models, whereas the effect of this mixing is significant. It is argued that the mixing role of the surface waves is not limited to the mere transfer of the wind stress and energy across the ocean interface by means of breaking and surface currents. The waves facilitate two processes in the upper-ocean which can deliver turbulence to the depths of the order of 100m directly, rather than diffusing it from the surface. The first process is due to capacity of the waves to generate turbulence, unrelated to the wave breaking, at all depths where the wave orbital motion is significant. The second process is Langmuir circulation, triggered by the waves. Such wave-controlled mixing should cause seasonal variations of the mixed-layer depth, which regulates the thermodynamic balance between the ocean and atmosphere. In the present paper, these variations are parameterized in terms of the global winds. The variable mixed-layer depth is then introduced in the climate model of intermediated complexity CLIMBER-2 with a purpose of reproducing the pre-industrial climate. Comparisons are conducted with the NRL global atlas of the mixed layer, and performance of the wave-mixing parameterisations was found satisfactory in circumstances where the mixing is expected to be dominated by the wind-generated waves. It is shown that as a result the seasonal temperature modulations and extremes are significantly enhanced. This effect combines with changes in the global pressure patterns and leads to large localized alterations of precipitation. Possible future scenarios are also simulated. Finally, importance of the wave-mixing physics and its relevance for the general circulation models is discussed. [Copyright &y& Elsevier]

We have investigated the dispersion of tracer particles by numerically simulating ensemble nonlinear gravity waves on the surface of an infinitely deep fluid. Using the concepts of passive Lagrangian markers and insights from weak wave turbulence theory, we validated fundamental predictions for particle kinematics associated with scaling laws and probability density functions. These results improve the understanding of wave-driven transport phenomena that depart far from equilibrium and the development of the high-fidelity models of transport processes in geophysical systems. • Dispersion of particles by nonlinear water waves has been investigated numerically. • Predictions of the Weak Wave Turbulence Theory have been confirmed. • The self-similarity form for Probability Density Function has been validated. [ABSTRACT FROM AUTHOR]

• Scaling exponent of velocity structure-function is evaluated up 15th order. • Different models of intermittency for wave turbulence have been validated. • She-Leveque model of intermittency provides a better fit for numerical data. The intermittency of gravity wave turbulence on the surface of an infinitely deep fluid has been studied numerically. We estimated the scaling exponent of surface elevation structure-functions directly from the equations of motion, e.g., by numerical solution of the underlying equations of motion, without any additional closure assumptions (e.g., phase randomisation) and reduction to the kinetic equations as in the conventional framework of wave turbulence theory. With our high-resolution numerical methods for accurately modelling the nonlinear water surface, we were able to evaluate the scaling exponents of the structure-function up to relatively high orders (p = 15), which has not been previously reported. We investigated the effect of wave steepness and forcing on intermittency and compared our results with other analytical and numerical studies, including results on the intermittency of wave turbulence of a different nature (turbulence of bending waves on a plate and magnetohydrodynamic turbulence). Our results support the conjecture of universality for intermittency phenomena in wave turbulence. [ABSTRACT FROM AUTHOR]

The vortex generation and dissipation accompanying Bragg scattering of water waves propagating over a series of submerged rectangular breakwaters are investigated both numerically and experimentally. The present model, which takes effects of non-linearity, viscosity and turbulence into consideration, is applied to simulate the entire vortex evolution process as water waves pass over a series of artificial rectangular bars. Particle image velocimetry is used to measure the velocity field in the vicinity of the bars. The numerical model is validated via a comparison with measured water surface elevations and velocity fields; the results show good agreement. The mechanism of vortex evolution and its influence on the interaction of water waves with submerged structures for cases with and without resonance are studied. The corresponding wave reflection coefficients for both cases are calculated and compared with experimental data and solutions based on linear wave theory. Examination of the turbulence properties shows that the turbulent intensity decreases on the weather side but increases on the lee side under the Bragg scattering conditions. [ABSTRACT FROM AUTHOR]