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Estimating gravity wave parameters from oblique high-frequency backscatter: Modeling and analysisA new technique for estimating electron density perturbation amplitudes of traveling ionospheric disturbances (TIDs), using HF radar data, is presented. TIDs are observed in HF radar data as enhancements of the ground-scattered power which propagate through the radar's field of view. These TIDs are the ionospheric manifestation of atmospheric acoustic-gravity waves. TID electron density perturbation amplitudes were estimated by simulating the radar returns, using HF ray tracing through a model ionosphere perturbed by a model gravity wave. The simulation determined the return power in the ground-scattered portion of the signal as a function of range, and this was compared to HF radar data from the Goose Bay HF radar at a time when evidence of gravity waves was present in the data. By varying the amplitude of the electron density perturbation in the model it was possible to estimate the perturbation of the actual wave. It was found that the perturbations that are observed by the Goose Bay HF radar are of the order of 20% to 35%. It was also found that the number of observable power enhancements, and the relative amplitudes of these enhancements, depended on the vertical thickness of the gravity wave's source region. From the simulations and observations it was estimated that the source region for the case presented here was approximately 20 km thick. In addition, the energy in the wave packet was calculated and compared to an estimate of the available energy in the source region. It was found that the wave energy was about 0.2% of the estimated available source region energy.
Document ID
19950047167
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Bristow, W. A.
(Johns Hopkins University Laurel, MD, United States)
Greenwald, R. A.
(Johns Hopkins University Laurel, MD, United States)
Date Acquired
August 16, 2013
Publication Date
March 1, 1995
Publication Information
Publication: Journal of Geophysical Research
Volume: 100
Issue: A3
ISSN: 0148-0227
Subject Category
Geophysics
Accession Number
95A78766
Funding Number(s)
CONTRACT_GRANT: NSF ATM-93-20146
CONTRACT_GRANT: NSF ATM-89-20887
CONTRACT_GRANT: NAG5-1099
Distribution Limits
Public
Copyright
Other

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