An Alternative Approach to the Parameterization the Momentum Flux Over the Sea

In this study we search for the optimal wave parameters characterizing the effect of waves on the air–sea momentum flux. When an attempt using traditional statistics failed to give an unequivocal answer, we applied a neural network approach. This led to a clear choice for the optimal parameters viz. the wind speed at a level equal to the wave height and the wavelength at the peak of the spectrum. With this set we could find a dimensionally correct parameterization that gave a close fit to our stress data, obtained in the southern North Sea. A comparison with open ocean data gave comparable results, allowing a generally applicable formulation. Wave breaking could explain the remaining small differences between the two sets of stress data.