Effects of bottom friction on continental shelf waves

The effects of bottom friction on a continental shelf wave for which σ f is 0(1), where σ is a wave frequency and f is the Coriolis parameter, are investigated. Rotational motions in the bottom boundary layer, which are ignored in conventional parameterizations of bottom friction having the form ru H, are considered in this study. Here, r is a friction coefficient, H is depth and u is a velocity vector. The results are as follows: (i) The rotational motions cause a decrease in damping and a modification in frequency compared to the results obtained with ru H: (ii) Friction in the form ru H is only applicable if σ f ≪ 1. Further work has examined the wavenumber dependence of these effects for linear friction using an exponential depth profile. A wind-forced model, in which the frequency of wind forcing is relatively high, has also been investigated.