The Response of Ocean Waves to Turning Winds

A model is developed for the response of waves to turning wind, which we denote as the fetch relaxation model. Comparison is presented with the standard 𝒷 relaxation model pioneered by Hasselmann et al. The fetch relaxation model is shown to surpass the standard 𝒷 model, with respect to observations collected during the Canadian Atlantic Storm Program (CASP) of 1986. Both models are based on the premise that the net growth of energy due to the wind is centered on the wind direction. The fetch relaxation model also conforms to relations for fetch-limited growing waves derived from the CASP observations. Moreover, the fetch relaxation model is shown to provide estimates for the role of the drag coefficient in turning wind situations.