On open boundary conditions for a limited-area coastal model off Oregon. Part 2: response to wind forcing from a regional mesoscale atmospheric model

This is the second part of a study of open boundary conditions (OBCs) in a limited-area high resolution coastal model off Oregon. In this paper, the OBCs developed in Part 1 [Ocean Modeling, 2005] are further evaluated by an application in which the coastal ocean model is forced with time- and space-dependent wind fields from a regional mesoscale atmospheric model [Journal of Geophysical Research––Oceans 107 (2002)]. The response during summer 1999 of the wind-driven upwelling flow field over the variable shelf bottom topography off Oregon coast is described. Satisfactory performance of the model and of the OBCs in this experiment with complex spatially and temporally varying atmospheric forcing is indicated by the production of physically reasonable fields in the ocean variables and by favorable model/data comparisons. Additional experiments forced by realistic, time-variable, but spatially uniform winds are included to allow a direct comparison of solutions obtained with OBCs and with cyclic boundary condition (CBCs). The general similarity of the results in these two cases provides additional support for the effectiveness of the OBCs in integrating the outer fluxes into, and radiating coastal trapped waves and advective disturbances out of, the computational domain.