Coherent Spatial Patterns and Material Transport in Oceanic Flows
Abstract
This is a grant for a theoretical and computational research program on the nonlinear dynamics of ocean currents. Its particular targets are the coherent patterns of flow which emerge in turbulence, and the mechanisms they provide for the transport and mixing of material properties in the fluid. This type of behavior is believed to occur quite generally, and this belief is tested by focusing on four oceanic regimes: (1) mid-latitude, wind-driven gyres and mesoscale eddies in bounded ocean basins, (2) coastal currents near irregular topography and coastlines and the eddies they generate, (3) plumes, vortices, and Langmuir cells in marine planetary boundary layers, in both the lower atmosphere and upper ocean, and (4) the dynamical influences of surface gravity waves on upper ocean currents and eddies through the vortex force proportional to their Stokes drift and other time-averaged effects, both in deep water and in the littoral zone. As a general framework for these particular topics, research also is being done on the general theory of vortices, geophysical turbulence, and Lagrangian dynamics, as well as on improvements in computational methods. The methodology in each regime is to obtain accurate computational solutions of canonical examples of the phenomena using a collection of (mostly) previously developed numerical models, to educe the dominant coherent structures and analyze their space-time behavior and governing dynamical processes, and to integrate families of parcel trajectories in the velocity fields they provide to determine their mechanisms for Lagrangian transports.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 31, 1998
- Accession Number
- ADA353916
Entities
People
- James C. McWilliams
Organizations
- University of California, Los Angeles