Collaborative Research: Equilibration of Ocean Currents via Inertial Instability

University Of Hawaii, Honolulu

Investigators

Abstract

Inertial instability occurs in rotating flows and results in the growth of perturbations in the form of streamwise vortices. If the intial flow is avortex, these perturbations take the form of toroidal or rib vortices. As they amplify, they begin to interact, forming dipoles that move out of the initially unstable region. In axisymmetric flows, the net effect of the motion and interaction of these vortices is homogenization of potential vorticity, forcing it to vanish in the instability region and beyond which then stabilizes the flow. Recently, scientists from Scripps Institute of Oceanography and the University of Hawaii have found that they can predict, with remarkable precision, the final state after this nonlinear process. They now plan to develop this theory for predicting the evolution of other kinds of vortices as well. Their work will involve numerical and theoretical research of three-dimensional flows and ill consider how this process competes with other instabilities. The results have implcations for the stabilization and maintenance of oceanic currents and eddies. In addition, the results will have an impact on the the development of models which can not resolve small scale processes.