MMM SEMINAR NCAR
McGill University
Montréal, Québec, Canada
Strongly stratified flows are composed of vortical motion (with PV) and internal gravity waves. At the largest scales of the atmosphere and ocean where Coriolis effects are strong, vortical motion dominates and is described well by quasigeostrophic turbulence theory. Moving downscale into the atmospheric mesoscale and oceanic submesoscale, rotational effects weaken. In the (inviscid) limit of strong stratification and weak rotation, the vertical scale of the vortical motion collapses, and its dynamics reduce to decoupled layers of two-dimensional turbulence. In a real fluid, of course, the scale does not collapse. It is limited by viscosity, small-scale turbulence, or rotation. In this talk, simulations of stratified turbulence forced by vortical motion are presented for a wide range of stratifications. We are particularly interested in the gap between stratified and QG turbulence and how the spectra and scales vary as the Rossby number goes from infinity to O(1). Implications for atmosphere/ocean modelling will be discussed.
Thursday, 24 February 2005,
3:30 PM
Refreshments 3:15 PM
NCAR-Foothills Laboratory
3450 Mitchell Lane
Bldg 2 Auditorium (Rm1022)