Seminar: Dr. Brian Arbic, University of Michigan
Dr. Brian Arbic joins us from the department of Earth and Environmental Sciences from the University of Michigan for his seminar titled The internal gravity wave spectrum: Â A new frontier for global ocean models. Refreshments will be served.
Abstract
In recent years increased computing power has allowed large supercomputing centers to run global ocean general circulation models at horizontal resolutions of 1/12th degrees or even higher (the current record is 1/48th degrees). At these resolutions, if in addition tidal forcing is included alongside atmospheric forcing, an internal gravity wave spectrum begins to develop. We show that the horizontal wavenumber-frequency spectrum fills out along predicted linear dispersion curves, and we show that it fills out more completely as horizontal resolution is increased. The nonlinear spectral transfers of kinetic energy also fill out along the dispersion curves, and increase in vigor with an increase in horizontal resolution. Finally, the comparison of modeled internal gravity wave frequency spectra with moored observations improves with increasing horizontal resolution. We discuss the implications of this work for understanding mixing in the ocean.