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Mesospheric gravity-wave climatology at AdelaideThe MF Adelaide partial-reflection radar has been operating continuously since November 1983. This has enabled a climatology of gravity-wave activity to be constructed for the mesosphere. The data have been analyzed for a medium-period range of 1 to 8 hr. and a longer period range between 8 and 24 hr. covering the inertio-period waves. The tidal motions have been filtered out prior to analysis. For the data analyses so far (Nov. 1983 to Dec. 1984), a number of interesting features emerged. Firstly, the wave activity at heights above 80 km shows a small seimannual variation with season with the activity being strongest in summer and winter. At heights below 80 km however, there is a similar but more marked variation with the weakest amplitudes occurring at the time of the changeovers in the prevailing circulation. If breaking gravity waves are responsible for much of the turbulence in the mesosphere, then the periods March to April and September to October might also be expected to be periods of weak turbulence. The wave field appears to be partially polarized. The meridional amplitudes are larger than the zonal amplitudes, especially in water. It is found that the degree of polarization is about 15% in summer and 30% in winter. The polarized component is found to propagate in the opposite direction to the background flow in the stratosphere, which suggests that the polarization arises through directional filtering of the waves as they propagate up from below.
Document ID
19870001023
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Vincent, R. A. (Adelaide Univ.)
Date Acquired
August 13, 2013
Publication Date
June 1, 1986
Publication Information
Publication: International Council of Scientific Unions, Middle Atmosphere Program. Handbook for MAP, Vol. 20
Subject Category
Geophysics
Accession Number
87N10456
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

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IDRelationTitle19870000986Collected WorksMiddle Atmosphere Program. Handbook for MAP, volume 20
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