Accession Number:

ADA439109

Title:

Remote Sensing of Gravity Wave Intensity and Temperature Signatures at Mesopause Heights Using the Nightglow Emissions

Descriptive Note:

Corporate Author:

AIR FORCE RESEARCH LAB HANSCOM AFB MA SPACE VEHICLES DIRECTORATE

Report Date:

2003-01-01

Pagination or Media Count:

14.0

Abstract:

During the past four decades a variety of optical remote sensing techniques have revealed a rich spectrum of wave activity in the upper atmosphere. Many of these perturbations, with periodicites ranging from 5 min to several hours and horizontal scales of a few tens of km to several thousands km, are due to freely propagating buoyancy or acoustic-gravity waves, and forced tidal oscillations. Optical observations of the spatial and temporal characteristics of these waves in the mesosphere and lower thermosphere MLT region 80-100 km are facilitated by several naturally occurring, vertically distinct nightglow layers. This paper describes the use of state-of-the-art ground-based CCD imaging techniques to detect these waves in intensity and temperature. All-sky 180 image measurements from Bear Lake Observatory, Utah are used to illustrate the characteristics of small-scale, short period 1 hour waves that are most frequently observed at MLT heights including a particular set of ducted wave motions, possibly associated with mesospheric bores. These results are then contrasted with measurements of mesospheric temperature made using a separate imaging system capable of determining induced temperature amplitudes of much larger-scale wave motions and investigating night-to-night and seasonal variability in mesospheric temperature.

Subject Categories:

  • Atmospheric Physics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE