An Oceanic Mixed Layer Model Capable of Simulating Cyclic States

Abstract

A new one-dimensional bulk model of the mixed layer of the upper ocean is presented. An entrainment hypothesis dependent upon the relative distribution of turbulent energy between horizontal and vertical components is offered as a plausible mechanism for governing both entrainment and layer retreat. This model has two properties not previously demonstrated. The fraction of wind-generated turbulent kinetic energy partitioned to potential energy increase by means of mixed layer deepening is dependent upon layer stability, H*=h/L, as measured by the ratio of mixed layer depth h to Obukhov length L. This results in a modulation of the mean entrainment rate by the diurnal heating and cooling cycle. Viscous dissipation is enhanced for increased values of 1/Ro=hf/u*, where f is the Coriolis parameter and u* the friction velocity for the water. This enables a cyclical steady state to occur over an annual period by limiting maximum layer depth. A nondimensional framework used to present the general solution also suggests a basis for model comparison and data analysis.

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Document Details

Document Type
Technical Report
Publication Date
Sep 24, 1976
Accession Number
ADA042470

Entities

People

  • Roland W. Garwood Jr.

Organizations

  • Naval Postgraduate School

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Boundary Layer
  • Buoyancy
  • Data Analysis
  • Dynamics
  • Energy
  • Equations
  • Heat Flux
  • Internal Waves
  • Kinetic Energy
  • Layers
  • Mechanical Energy
  • Oceans
  • Potential Energy
  • Richardson Number
  • Steady State
  • Turbulence
  • Wind Stress

Readers

  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Fluid Dynamics.
  • Ocean-Atmosphere Mesoscale Modeling, Data Assimilation, and Flux Boundary Layers