Relating Friction Velocity to Spectral Wave Parameters

Abstract

Field experiments, in the years since the JONSWAP results, have established fetch- and duration-limited relations for wave parameters such as total energy E0, peak frequency fp, and the Phillips α coefficient. The Canadian Atlantic Storms Program (CASP) Experiment of 1986 also found that the wind speed profile appropriate for the fetch-limited wave relations is a function of fetch, due to the change in surface roughness at the shoreline. Moreover, the fetch-limited wave relations may be altered by assuming differing wind speed variations with fetch. Inverting accepted fetch-limited wave relation the authors inter a fetch-limited relation for wind speed (or friction velocity) in terms of spectral wave parameters such as wave age. These relations are verified from measurements collected during CASP.