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Large‐scale offshore wind farms are expected to influence surface waves by modifying local wind forcing through wake effects. We use regional coupled ocean‐atmosphere‐wave model simulations to investigate a realistic large‐scale offshore wind development scenario in the northeastern U.S. during boreal summer. Near‐surface wind speeds are reduced by 10% over lease areas and within downstream wake regions, leading to decreases in significant wave height (3%) and wave‐supported momentum flux (30%). This further leads to reductions in surface roughness length (16%) and near‐surface ocean turbulent kinetic energy (20%). Spectral analysis shows a clear reduction in wind‐sea energy, indicating suppressed local wind‐wave growth near the wind farms. Weaker winds favor the development of longer‐period waves, increasing dominant wave phase speed by 3% and suggesting a transition to an older sea state. Modern bulk flux algorithms often parameterize surface roughness using inverse wave age and/or wave slope. This raises the question of whether wake‐driven reductions in inverse wave age and wave height impact air‐sea momentum exchange. To assess this, we compare fully coupled simulations with an atmosphere‐only run excluding wave coupling. Results show that about one‐third of the reduction in roughness length can be attributed to sea state changes, while two‐thirds result from lower friction velocity due to lower wind speeds. However, the impact of sea state on the drag coefficient and momentum flux is negligible (1%), suggesting that wake‐induced wind speed reductions are the primary driver, with sea state changes playing a secondary role. 

Recent results using wind and sea surface temperature data from satellites and high-resolution coupled models suggest that mesoscale ocean–atmosphere interactions affect the locations and evolution of storms and seasonal precipitation over continental regions such as the western US and Europe. The processes responsible for this coupling are difficult to verify due to the paucity of accurate air–sea turbulent heat and moisture flux data. These fluxes are currently derived by combining satellite measurements that are not coincident and have differing and relatively low spatial resolutions, introducing sampling errors that are largest in regions with high spatial and temporal variability. Observational errors related to sensor design also contribute to increased uncertainty. Leveraging recent advances in sensor technology, we here describe a satellite mission concept, FluxSat, that aims to simultaneously measure all variables necessary for accurate estimation of ocean–atmosphere turbulent heat and moisture fluxes and capture the effect of oceanic mesoscale forcing. Sensor design is expected to reduce observational errors of the latent and sensible heat fluxes by almost 50%. FluxSat will improve the accuracy of the fluxes at spatial scales critical to understanding the coupled ocean–atmosphere boundary layer system, providing measurements needed to improve weather forecasts and climate model simulations.