and S on the right-hand side of Eq.

and S on the right-hand side of Eq. (3) is the source function. Although there is consensus among the wave community on Eq. (3), there are quite diverse views about the exact representation of S. The most widely ac- cepted view suggests that S represents the physics of wind-wave generation (Sin), dissipation by wave breaking and other causes (Sdissip) and four-wave interactions (Snonlin). In other words,