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This work serves as an observation‐based exploration into the role of wave‐driven turbulence at the air‐sea interface by measuring Turbulent Kinetic Energy (TKE) dissipation rates above and below the sea surface. Subsurface ocean measurements confirm a TKE dissipation rate enhancement relative to the predicted law‐of‐the‐wall (εobs > εp), which appears to be fully supported by wave breaking highlighting the role of the transport terms in balancing the subsurface TKE budget. Simultaneous measurements of TKE dissipation rates on the atmospheric side capture a deficit relative to the law‐of‐the‐wall (εobs < εp). This deficit is explained in terms of wave‐induced perturbations, with observed convergence to the law‐of‐the‐wall at 14 m above mean sea level. The deficit on the atmospheric side provides an estimate of the energy flux divergence in the wave boundary layer. An exponential function is used to integrate in the vertical and provide novel estimates of the amount of energy going into the wave field. These estimates correlate well with classic spectral input parameterizations and can be used to derive an effective wave‐scale, capturing wind‐wave coupling purely from atmospheric observations intimately tied to wave‐induced perturbations of the air‐flow. These atmospheric and oceanic observations corroborate the commonly assumed input‐dissipation balance for waves at wind speeds in the 8‐14 ms−1 range in the presence of developed to young seas. At wind speeds above 14 ms−1 under young seas (U10cp>1.2 $\sfrac{{U}_{10}}{{c}_{p}} > 1.2$)observations suggest a deviation from the TKE input‐dissipation balance in the wave field. Plain Language Summary: A long‐term field campaign on the Western North Atlantic shelf provided observations of Turbulent Kinetic Energy (TKE) dissipation rates on both sides of the sea surface. These observations were used to track the energy exchange between the atmosphere and ocean that is mediated by surface waves. Deviations from the expected law‐of‐the‐wall scaling in our TKE dissipation rate estimates were linked to wind energy input leading to wave growth, wave breaking and the subsequent TKE injection into the water column. Observations confirm the subsurface enhancement of TKE relative to the classic law‐of‐the‐wall and showcase a TKE deficit on the atmospheric side. Atmospheric and oceanic TKE dissipation rates converge to the expected law‐of‐the‐wall profiles away from the surface but clearly show the importance of waves in atmosphere‐ocean interaction closer to the sea surface. Deviations from the law‐of‐the‐wall are presented as signature of wave‐induced turbulence close to the ocean surface. Key Points: Turbulent Kinetic Energy (TKE) dissipation rates across the interface show a deficit and enhancement supported by the wave fieldA depth integrated subsurface TKE budget highlights the relevance of the transport terms and their connection to wave breakingThe atmospheric TKE dissipation rate deficit can be explained in terms of wave‐induced perturbations mediating energy input to the waves [ABSTRACT FROM AUTHOR]

Bubble plume penetration depths have been identified as a key parameter linking subsurface turbulent kinetic energy (TKE) dissipation rates and whitecaps. From data collected in the Atlantic sector of the Southern Ocean, nominally 50°S 40°W, bubble plume penetration depths were estimated from Acoustic Doppler Current Profiler measurements of the acoustic backscatter anomaly. Bubble presence at depth was corroborated using independent measurements of optical scattering. Here, an effective wavelength, observations of significant wave height and atmospheric forcing were used to scale penetration depths of breaking waves under open ocean conditions. The parameterization was developed assuming a correlation between the observed penetration depth and an estimate of the TKE dissipation rate enhancement under breaking waves. The effective wavelength was defined from the effective phase speed based on a momentum and energy balance across the atmospheric wave boundary layer and was considered to be the largest actively wind‐coupled wave and representative of large‐scale breaking for wave ages ranging from 15 to 35 (i.e., 15 ≤ 〈cp/u*〉 ≤ 35). This yields a dimensional penetration depth parameterization in terms of inverse wave age and the length scales under consideration. The parameterization captures the bubble plume penetration depth with stronger forcing leading to deeper injections, reaching up to 9 m. Both length scales are effective at defining the depth of a wave‐affected layer in terms of bubble presence with the effective wavelength better collapsing the data under mixed conditions with deeper plumes associated to larger fractional whitecap coverage. Plain Language Summary: The depth to which waves breaking at the ocean surface influence oceanic processes in the mixed layer, including the transfer of momentum, heat and gases between the atmosphere and ocean, is an ongoing and active area of research. Parameterizations and observations describing the vertical extent of wave‐driven effects, including whitecaps and vertical jets associated with Langmuir circulation, are relevant for numerical circulation models and our understanding of wave breaking and dissipation dynamics. Here, observations of atmospheric and oceanic conditions, principally wind, wave, and inferred bubble plume penetration depths collected in the Atlantic sector of the Southern Ocean were used to build a parameterization for estimating the vertical extent of bubble injections and for inferring the depth of the wave‐affected layer. These results suggest that wavelengths shorter than the dominant peak and significant wave heights properly weighted by atmospheric parameters are a good proxy for defining the extent of wave‐driven bubble transport. Key Points: The significant wave height and the effective wavelength were used to scale bubble penetration depths under open ocean conditionsBoth length scales successfully provide a penetration depth parameterization with the effective wavelength better collapsing the data [ABSTRACT FROM AUTHOR]