Accession Number:

ADA171998

Title:

Dynamical - Chemical Coupling in the Mesosphere and Lower Thermosphere.

Descriptive Note:

Final rept. 1 Jun-1 Dec 84,

Corporate Author:

BOSTON UNIV MA DEPT OF ELECTRICAL COMPUTER AND SYSTEMS ENGINEERING

Personal Author(s):

Report Date:

1985-01-31

Pagination or Media Count:

4.0

Abstract:

The dynamic ionosphere over Arecibo is simulated using a finite element technique. It is shown that the so-called collapse of the Arecibo F-layer is caused by the upward-propagating semidiurnal tide excited in the upper stratosphere by ozone heating. The steep underside density gradients observed in conjunction with the collapse are shown to be due to the shear in the meridional wind field of the semidiurnal tide. These gradients are capable of triggering the gradient drift plasma instability, and accounting for plasma irregularity formation and observations of VHF scintillations associated with the collapse phenomenon.

Subject Categories:

  • Atmospheric Physics
  • Meteorology

Distribution Statement:

APPROVED FOR PUBLIC RELEASE