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Abstract Energy is transferred from the atmosphere to the ocean primarily through ocean surface waves, and the majority is dissipated locally in the near‐surface ocean. Observations of turbulent kinetic energy (TKE) in the upper ocean have shown dissipation rates exceeding law‐of‐the‐wall theory by an order of magnitude. The excess near‐surface ocean TKE dissipation rate is thought to be driven primarily by wave breaking, which limits wave growth and transfers energy from the surface wave field to the wave‐affected layer of the ocean. Here, the statistical properties of breaking wave dynamics in a coastal area are extracted from visible imagery and used to estimate TKE dissipation rates due to breaking waves. The statistical properties of whitecap dynamics are quantified with Λ(c), a distribution of total whitecap crest length per unit area as a function of crest speed, and used to compute energy dissipation by breaking waves, S_ds. S_dsapproximately balances elevated subsurface dissipation in young seas but accounts for only a fraction of subsurface dissipation in older seas. The wind energy input is estimated from wave spectra from polarimetric imagery and laser altimetry. S_dsbalances the wind energy input except under high winds. Λ(c)‐derived estimates of TKE dissipation rates by breaking waves compare well with the atmospheric deficit in TKE dissipation, a measure of energy input to the wave field (Cifuentes‐Lorenzen et al., 2024). These results tie the observed atmospheric dissipation deficit and enhancement in subsurface TKE dissipation to wave driven energy transport, constraining the TKE dissipation budget near the air‐sea interface. 

Abstract 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 (ε_obs > ε_p), 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 (ε_obs < ε_p). 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⁻¹range in the presence of developed to young seas. At wind speeds above 14 ms⁻¹under young seas ()observations suggest a deviation from the TKE input‐dissipation balance in the wave field. 

SUMMARY We determine crustal shear wave velocity structure and crustal thickness at recently deployed seismic stations across West Antarctica, using a joint inversion of receiver functions and fundamental mode Rayleigh wave phase velocity dispersion. The stations are from both the UK Antarctic Network (UKANET) and Polar Earth Observing Network/Antarctic Network (POLENET/ANET). The former include, for the first time, four stations along the spine of the Antarctic Peninsula, three in the Ellsworth Land and five stations in the vicinity of the Pine Island Rift. Within the West Antarctic Rift System (WARS) we model a crustal thickness range of 18–28 km, and show that the thinnest crust (∼18 km) is in the vicinity of the Byrd Subglacial Basin and Bentley Subglacial Trench. In these regions we also find the highest ratio of fast (Vs = 4.0–4.3 km s–1, likely mafic) lower crust to felsic/intermediate upper crust. The thickest mafic lower crust we model is in Ellsworth Land, a critical area for constraining the eastern limits of the WARS. Although we find thinner crust in this region (∼30 km) than in the neighbouring Antarctic Peninsula and Haag-Ellsworth Whitmore block (HEW), the Ellsworth Land crust has not undergone as much extension as the central WARS. This suggests that the WARS does not link with the Weddell Sea Rift System through Ellsworth Land, and instead has progressed during its formation towards the Bellingshausen and Amundsen Sea Embayments. We also find that the thin WARS crust extends towards the Pine Island Rift, suggesting that the boundary between the WARS and the Thurston Island block lies in this region, ∼200 km north of its previously accepted position. The thickest crust (38–40 km) we model in this study is in the Ellsworth Mountain section of the HEW block. We find thinner crust (30–33 km) in the Whitmore Mountains and Haag Nunatak sectors of the HEW, consistent with the composite nature of the block. In the Antarctic Peninsula we find a crustal thickness range of 30–38 km and a likely dominantly felsic/intermediate crustal composition. By forward modelling high frequency receiver functions we also assess if any thick, low velocity subglacial sediment accumulations are present, and find a 0.1–0.8-km-thick layer at 10 stations within the WARS, Thurston Island and Ellsworth Land. We suggest that these units of subglacial sediment could provide a source region for the soft basal till layers found beneath numerous outlet glaciers, and may act to accelerate ice flow.