Topographic influences in the California current system

Abstract

A ten-level primitive equation numerical model is used to study the influences of the bottom topography in the California Current System. Five different numerical experiments were integrated for 40 days after being initialized with a baroclinic alongshore coastal jet representative of the observed coastal jet. By comparison with a flat bottom case, in Experiments 1 and 3, in which the topographic slopes face westward or northward, the topography appears to have stabilizing influences on the mean flow. In Experiments 2 and 4, in which the topographic slopes face southward, the topographic B-effect appears to be strong enough so that these two cases have already reached a quasi-steady state by 40 days. This is because in Experiments 2 and 4 the long, nondispersive topographic Rossby waves are effective at transporting the eddy energy away from the source region near the coast. The resulting new mean flow appears to be stable.