ACOUSTIC WAVES IN THE IONOSPHERE,

Abstract

The independent solutions which correspond to an upgoing and downgoing acoustic wave in a viscous, non-heat conducting isothermal atmosphere are derived. The behavior of the perturbation density associated with the upgoing wave for large 1/Re is examined and found to be non-oscillatory. Houtl has shown that in the 100-130 kilometer region there are observed oscillations associated with the perturbation density of random acoustic waves. From the non-oscillatory behavior it is deduced that neither molecular nor eddy viscousity can be the damping mechanism. Further it is shown that including thermal conductivity cannot produce the observed oscillations. The thermal gradient in the atmosphere is proposed to be a possible source of wave attenuation. The propagation of the upgoing wave through a small temperature jump is examined, and the effect of the discontinuity on the wave amplitude is found to be significant. (Author)

Document Details

Document Type
Technical Report
Publication Date
Aug 20, 1967
Accession Number
AD0658449

Entities

People

  • L. H. Wight

Organizations

  • Pennsylvania State University

Tags

DTIC Thesaurus Topics

  • Acoustic Waves
  • Amplitude
  • Atmospheres
  • Attenuation
  • Conductivity
  • Discontinuities
  • Ionosphere
  • Oscillation
  • Perturbations
  • Temperature Gradients
  • Thermal Conductivity
  • Waves

Fields of Study

  • Physics

Readers

  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Fluid Dynamics.