Measurements of Structural Features in Profiles of Mesospheric Density
Document ID: 36
USAF, Geophysics Laboratory, Hanscom AFB, Bedford, MA, U.S.A.
Presented: International Symposium on Middle Atmosphere Dynamics and Transport
Urbana, Illinois, July 28 - August 1, 1980
Abstract
Recent measurements using a higher sensitive piezoelectric accelerometer in a falling sphere have been examined to study the detail structure features in vertical profiles of the mesospheric density. The measurements have a vertical resolution of about 100 meters through the mesosphere. Features with scale sizes of 500 meters or larger and amplitudes greater than 1% could be perceived in the data. The minimum structure scale size observed in the 60 km region has been about 1.5 km and in the 90 km region about 3 km. The vertical scales of the atmospheric density structures have been examined for consistency with those expected for gravity waves and tidal features in the region between 50 and 120 km. The measurements have also been examined to define those regions that would be statically unstable based on the logarithmic density gradient being less than the density adiabat. In the few sets of high resolution measurements obtained to date, all have exhibited regions of static instability which are probably associated with layers of intense turbulence in the mesosphere.
| Citation: | "Measurements of Structural Features in Profiles of Mesospheric Density", Philbrick, C. R., Handbook for MAP, Vol. 2, Middle Atmosphere Program, 1981, pp. 333 - 340 |