DYNAMIC MEAN FLOW AND SMALL-SCALE INTERACTION THROUGH TOPOGRAPHIC STRESS

The equations describing the mean flow and small-scale interaction of a barotropic flow via topographic stress with layered topography are s tudied here through the interplay of theory and numerical experiments. Both a viewpoint toward atmosphere-ocean science and one toward chaot ic nonlinear dynamics are emphasized. As regards atmosphere-ocean scie nce, we produce prototype topographic blocking patterns without dampin g or driving, with topographic stress as the only transfer mechanism; these patterns and their chaos bear some qualitative resemblance to th ose observed in recent laboratory experiments on topographic blocking. As regards nonlinear dynamics, it is established that the equations f or mean flow and small-scale interaction with layered anisotropic topo graphy form a novel Hamiltonian system with rich regimes of intrinsic conservative chaos, which include both global and weak homoclinic stoc hasticity, as well as other regimes with complete integrability involv ing complex heteroclinic structure.