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Ann. Geophys., 24, 2851-2862, 2006
www.ann-geophys.net/24/2851/2006/
© European Geosciences Union 2006
Inertia gravity waves in the upper troposphere during the MaCWAVE winter campaign – Part I: Observations with collocated radars
P. Hoffmann1, A. Serafimovich1, D. Peters1, P. Dalin2, R. Goldberg3, and R. Latteck1
1Leibniz-Institut für Atmosphärenphysik, Kühlungsborn, Germany
2Swedish Institute of Space Physics, Kiruna, Sweden
3NASA/Goddard Space Flight Center, Greenbelt, Maryland, USA
Abstract. During the {MaCWAVE} campaign, combined rocket, radiosonde and
ground-based measurements have been performed at the Norwegian
Andøya Rocket Range (ARR) near Andenes and the Swedish Rocket
Range (ESRANGE) near Kiruna in January 2003 to study gravity waves
in the vicinity of the Scandinavian mountain ridge. The
investigations presented here are mainly based on the evaluation
of continuous radar measurements with the ALWIN VHF radar in
the upper troposphere/ lower stratosphere at Andenes
(69.3° N, 16.0° E) and the ESRAD VHF
radar near Kiruna (67.9° N, 21.9° E).
Both radars are separated by about 260 km. Based on wavelet
transformations of both data sets, the strongest activity of
inertia gravity waves in the upper troposphere has been detected
during the first period from 24–26 January 2003 with dominant
vertical wavelengths of about 4–5 km as well as with
dominant observed periods of about 13–14 h for the
altitude range between 5 and 8 km under the additional
influence of mountain waves. The results show the appearance of
dominating inertia gravity waves with characteristic horizontal
wavelengths of ~200 km moving in the opposite
direction than the mean background wind. The results show the
appearance of dominating inertia gravity waves with intrinsic
periods in the order of ~5 h and with horizontal
wavelengths of 200 km, moving in the opposite direction
than the mean background wind. From the derived downward energy
propagation it is supposed, that these waves are likely generated
by a jet streak in the upper troposphere. The parameters of the
jet-induced gravity waves have been estimated at both sites
separately. The identified gravity waves are coherent at both
locations and show higher amplitudes on the east-side of the
Scandinavian mountain ridge, as expected by the influence of
mountains.
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