ANISOTROPY AND COHERENT VORTEX STRUCTURES IN PLANETARY TURBULENCE

High-resolution numerical simulations were made of unforced, planetary -scale fluid dynamics. In particular, the simulation was based on the quasi-geostrophic equations for a Boussinesq fluid in a uniformly rota ting and stably stratified environment, which is an idealization for l arge regions of either the atmosphere or ocean. The solutions show sig nificant discrepancies from the long-standing theoretical prediction o f isotropy. The discrepancies are associated with the self-organizatio n of the flow into a large population of coherent vortices. Their chao tic interactions govern the subsequent evolution of the flow toward a final configuration that is nonturbulent.