Under his previous award, Dr. Pedlosky and his colleagues have made important theoretical advances in research related to two general themes. The first is a continuing effort to better understand the dynamics of baroclinic instability in both linear and nonlinear theories, with special emphasis on the phenomena of vacillation and chaotic behavior. The research involves the use of idealized two-layer models to illuminate fundamental wave processes and the results are applicable to both atmospheric and oceanic dynamics. The second broad area involves the development of a basic theory for the general oceanic circulation, in particular, the thermocline and its extension of the equatorial regions. Under this award, Dr. Pedlosky will extend his previous results, using both analytical and numerical techniques. Five topics will be investigated: (1) the behavior of localized instabilities in zonally inhomogeneous flows, (2) wave-wave interaction under strongly nonlinear conditions, (3) the role of the dissipation mechanism in the wave evolution, (4) the relationship of the Equatorial Undercurrent to other circulations at the western boundary of ocean basins, and (5) the effect of steeply sloping topography on the dynamics and structure of oceanic western boundary currents. Support for this research is provided jointly by the Large-scale Dynamic Meteorology and Physical Oceanography Programs.
