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GEOPHYSICAL RESEARCH LETTERS,
VOL. 33,
L08808,
doi:10.1029/2005GL024345,
2006
Intense turbulence observed above a mesospheric temperature inversion at equatorial latitude
G. A. Lehmacher
Department of Physics and Astronomy, Clemson University, Clemson, South Carolina, USA
C. L. Croskey
Communications and Space Sciences Laboratory, Department of Electrical Engineering, Pennsylvania State University, University
Park, Pennsylvania, USA
J. D. Mitchell
Communications and Space Sciences Laboratory, Department of Electrical Engineering, Pennsylvania State University, University
Park, Pennsylvania, USA
M. Friedrich
Institute for Communications Networks and Satellite Communication, Graz University of Technology, Graz, Austria
F.-J. Lübken
Leibniz-Institute for Atmospheric Physics, Kühlungsborn, Germany
M. Rapp
Leibniz-Institute for Atmospheric Physics, Kühlungsborn, Germany
E. Kudeki
Department of Electrical and Computer Engineering, University of Illinois, Urbana, Illinois, USA
D. C. Fritts
Colorado Research Associates, Northwest Research Associates, Boulder, Colorado, USA
Abstract
Results from a sounding rocket experiment launched on September 19, 2004 from Kwajalein Atoll, Marshall Islands are reported.
A large modulation of the temperature profile in the upper mesosphere was observed with a local maximum at 92 km, 40 K warmer
than 2 km below. The temperature gradient between 92 and 102 km was near-adiabatic, suggesting strong mixing. Turbulence was
observed in the lower part of the mixed layer, as evidenced by neutral and plasma density fluctuations on both the upleg and
downleg portions of the flight. The plasma density gradient was less steep in the mixed region. The turbulent energy dissipation
rate was found to be 170 mW/kg. The thermal structure can be described as an upper mesospheric inversion layer, possibly caused
by enhanced wave breaking or turbulent heat transport.
Received 9
August
2005;
accepted 6
October
2005;
published 28
April
2006.
Index Terms: 0342 Atmospheric Composition and Structure: Middle atmosphere: energy deposition (3334); 3332 Atmospheric Processes: Mesospheric dynamics; 3334 Atmospheric Processes: Middle atmosphere dynamics (0341, 0342); 3369 Atmospheric Processes: Thermospheric dynamics (0358).
Subscriber Access to Full Article (Nonsubscribers may purchase for $9.00, Includes print PDF, file size: 301354 bytes)
Citation: Lehmacher, G. A., C. L. Croskey, J. D. Mitchell, M. Friedrich, F.-J. Lübken, M. Rapp, E. Kudeki, and D. C. Fritts
(2006),
Intense turbulence observed above a mesospheric temperature inversion at equatorial latitude,
Geophys. Res. Lett.,
33,
L08808,
doi:10.1029/2005GL024345.
Copyright 2006 by the American Geophysical Union.
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