Wind work in a model of the northwest Atlantic Ocean

The work done by the wind over the northwest Atlantic Ocean is examined using a realistic high-resolution ocean model driven by synoptic wind forcing. Two model runs are conducted with the difference only in the way the wind stress is calculated. Our results show that the effect of including ocean surface currents in the wind stress formulation is to reduce the total wind work integrated over the model domain by about 17%. The reduction is caused by a sink term in the wind work calculation associated with the presence of ocean currents. In addition, the modelled eddy kinetic energy decreases by about 10%, in response to direct mechanical damping by the surface stress. A simple scaling argument shows that the latter can be expected to be more important than bottom friction in the energy budget.