Coastal Mixing

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 wave's 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.

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1998
Accession Number
ADA551758

Entities

People

  • Eric A. D'Asaro

Organizations

  • University of Washington

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Boundary Layer
  • Buoyancy
  • Energy
  • Flow
  • Fluid Dynamics
  • Fluid Mechanics
  • Frequency
  • Internal Waves
  • Kinetic Energy
  • Oceans
  • Physics Laboratories
  • Reynolds Number
  • Shallow Water
  • Stratified Fluids
  • Turbulence
  • Turbulent Flow
  • Turbulent Mixing

Fields of Study

  • Environmental science

Readers

  • Ocean-Atmosphere Mesoscale Modeling, Data Assimilation, and Flux Boundary Layers
  • Plasma Physics / Magnetohydrodynamics
  • Systems Analysis and Design