Wave Age and Steepness Relation in Growing Wind Seas: A Case Study during Hurricane Matthew in 2016

For wind-wave interaction studies, from the literature, two criteria for the wind sea are used: one is the wave age and the other wave steepness. Analysis of pertinent datasets from a data buoy near the passage of Hurricane Matthew in 2016 indicates that = -15 + 1.3. Here is the wave age and is the wave steepness, where C_p is the phase speed of the peak wave, U₁₀ is the wind speed at 10 m, H_s is the significant wave height, and L_p is the peak or dominant wave length. It is found that 87% of the variation between wave age and wave steepness can be explained by this relation. Application of this relation to estimate U₁₀ and friction velocity from wave parameters are also presented for practical environmental and engineering use.