Saturation and the 'Universal' Spectrum for Vertical Profiles of Horizontal Scalar Winds in the Atmosphere

Abstract

A theory is presented which explains the universal nature of one-dimensional vertical wave number, k, power spectral densities (PSD's) of horizontal winds as measured in the atmosphere and predicted by VanZandt. The theory is that the PSD amplitude at any given wave number (greater than a certain minimum, k) is determined by its saturation value due either to shear instability (i.e., critical Richardson Number) or, more likely, to convective instability. This explains why the PSD amplitudes observed do not grow exponentially with increasing altitude. The full model not only explains the observed spectral slopes but also predicts the PSD amplitude in the troposphere to be 3.5 times smaller than in the stratosphere. The model may also apply to the ocean and explain the Garrett-Munk vertical wave number spectrum. Keywords: Reprints; Fluid mechanics, Atmospheric physics.

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Document Details

Document Type
Technical Report
Publication Date
Feb 20, 1986
Accession Number
ADA201752

Entities

People

  • E. M. Dewan
  • R. E. Good

Organizations

  • Air Force Research Laboratory

Tags

Communities of Interest

  • Weapons Technologies

DTIC Thesaurus Topics

  • Altitude
  • Amplitude
  • Buoyancy
  • Equations
  • Fluid Mechanics
  • Frequency
  • Gravity Waves
  • Internal Waves
  • Long Wavelengths
  • Measurement
  • Physics
  • Richardson Number
  • Spectra
  • Surface Waves
  • Troposphere
  • Turbulence
  • Waves

Fields of Study

  • Physics

Readers

  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.

Technology Areas

  • Space