Source terms
From Glossary of Meteorology
source terms
In spectral wave modeling, the contributions to net energy increase and decrease within each spectral band, due to such effects as energy input from the wind, nonlinear transfer of energy between different spectral components, energy dissipation by wave breaking, bottom stress, etc.
These contributions do not include the spatial flux of energy due to wave propagation or the flux in wavenumber space due to changes in water depth or current.