Accession Number:

ADA551758

Title:

Coastal Mixing

Descriptive Note:

Annual rept.

Corporate Author:

WASHINGTON UNIV SEATTLE APPLIED PHYSICS LAB

Personal Author(s):

Report Date:

1998-01-01

Pagination or Media Count:

4.0

Abstract:

The long-term goal of this research is to understand the mechanisms of turbulence and mixing in shallow water sufficiently well to be able to specify useful parameterizations for coastal circulation models. I believe that this goal can best be achieved through a combination of comprehensive measurement of the turbulent fluctuations and the larger scale flows that drive them, and modeling. These turbulent flows are often complex and rapidly changing and can be only properly measured using a combination of methods that measure a variety of spatial and temporal scales. My medium-term scientific objective is to make and analyze such measurements in cooperation with other investigators. My technical approach is to combine neutrally buoyant Lagrangian floats, acoustic remote sensing of various types, microstructure measurements, and rapid CTD profiling. This instrumental suite can both map a given flow and determine its mixing rates. It appears that stratified flows may be modeled as the sum of nearly isotropic turbulence and strongly anisotropic internal waves. All of the anisotropy is due to the internal wave component. For sufficiently strong turbulence, a simple relationship between the waves vertical kinetic energy and turbulence level exists which can provide a simple parameterization of the mixing rates. Accurate models of internal waves and turbulence are crucial for modeling shallow water circulations. Proper distinction between waves and turbulence is crucial for making such models, as are parameterizations of these processes.

Subject Categories:

  • Physical and Dynamic Oceanography
  • Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE