Accession Number : AD0658449

Title :   ACOUSTIC WAVES IN THE IONOSPHERE,

Corporate Author : PENNSYLVANIA STATE UNIV UNIVERSITY PARK IONOSPHERE RESEARCH LAB

Personal Author(s) : Wight,L. H.

Report Date : 20 AUG 1967

Pagination or Media Count : 37

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)

Descriptors :   (*MECHANICAL WAVES, *IONOSPHERE), ACOUSTICS, DENSITY, ATTENUATION, OSCILLATION, THERMAL PROPERTIES, PROPAGATION, MOTION, THESES

Subject Categories : Atmospheric Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE