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Ann. Geophys., 24, 1227-1243, 2006
www.ann-geophys.net/24/1227/2006/
© European Geosciences Union 2006
Propagation of short-period gravity waves at high-latitudes during the MaCWAVE winter campaign
K. Nielsen1, M. J. Taylor1, P.-D. Pautet1, D. C. Fritts2, N. Mitchell3, C. Beldon3, B. P. Williams2, W. Singer4, F. J. Schmidlin5, and R. A. Goldberg6
1Center for Atmospheric and Space Sciences and Physics Department, Utah State University, Logan, UT 84322, USA
2Colorado Research Associates, Northwest Research Associates, Boulder, CO 80301, USA
3Department of Electronic and Electrical Engineering, University of Bath, UK
4Leibniz-Institut für Atmosphärenphysik, Kühlungsborn, Germany
5NASA/Goddard Space Flight Center, Wallops Flight Facility, Code 972, Wallops Island, VA 23337, USA
6NASA/Goddard Space Flight Center, Code 612.3, Greenbelt, MD 20771, USA
Abstract. As part of the MaCWAVE (Mountain and Convective Waves Ascending
Vertically) winter campaign an all-sky monochromatic CCD imager
has been used to investigate the properties of short-period
mesospheric gravity waves at high northern latitudes. Sequential
measurements of several nightglow emissions were made from
Esrange, Sweden, during a limited period from 27–31 January
2003. Coincident wind measurements over the altitude range
(~80–100 km) using two meteor radar systems located at
Esrange and Andenes have been used to perform a novel
investigation of the intrinsic properties of five distinct wave
events observed during this period. Additional lidar and MSIS
model temperature data have been used to investigate their nature
(i.e. freely propagating or ducted). Four of these extensive wave
events were found to be freely propagating with potential source
regions to the north of Scandinavia. No evidence was found for
strong orographic forcing by short-period waves in the airglow
emission layers. The fifth event was most unusual exhibiting an
extensive, but much smaller and variable wavelength pattern that
appeared to be embedded in the background wind field. Coincident
wind measurements indicated the presence of a strong shear
suggesting this event was probably due to a large-scale
Kelvin-Helmholtz instability.
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