Gas Transfer by Breaking Waves

The transfer of gases at the ocean-atmosphere interface impacts weather and climate from local to global scales, with carbon dioxide (CO₂) key to marine life and ecosystems, and dimethyl sulfide affecting aerosols and atmospheric processes. However, the bubble-mediated gas transfer, associated with breaking waves has remained poorly constrained. We present a spectral framework for bubble-mediated gas transfer, computed from a mechanistic model for air bubble entrainment at the breaking wave scale combined with a chemical model. Gas transfer is upscaled to the ocean scale by evaluating air entrainment at all wave scales using wave and wave breaking statistics. The obtained CO₂ gas transfer velocity reproduces the variability of historical parameterizations and recent field measurements, with very good accuracy. We propose a wind-wave parameterization that collapses all available data, which can be directly implemented in ocean-wave models or used with remote sensing of the ocean surface to infer gas transfer.