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An analysis of the role of drift waves in equatorial spread FAn account is given of results of rocket measurements of the wave number spectrum of equatorial spread F irregularities, with emphasis on wavelengths less than 100 m. The measurements were made from two sounding rockets launched from Peru as part of Project Condor. The Condor density fluctuation spectra display a break at a wavelength near 100 m, identical to that found in the PLUMEX experiment (Kelley et al., 1982). The Condor data also confirm a subrange in which the density and the wave potential obey the Boltzmann relation - a strong indication of the presence of low-frequency electrostatic waves with finite wavelength parallel to the magnetic field, perhaps low-frequency drift waves as proposed by Kelley et al. The Condor data are also consistent with the previous conjecture that drift waves only exist above 300 km altitude. To investigate the difference in spectra observed over two altitude ranges, the data must be fitted to a form for the power spectrum taken from Keskinen and Ossakow (1981). The fitted spectrum, along with empirically determined growth and dissipation rates, is used to calculate the energy pumped into the spectrum at long wavelengths as well as the energy dissipated at shorter wavelengths. It is found that the energy is balanced by classical collisional effects in the low-altitude case, but energy balance in the high-altitude case requires an enhanced dissipation of about 500 times that due to classical diffusion. The model is consistent with, but does not uniquely imply, an inverse cascade of drift wave turbulence in equatorial spread F.
Document ID
19860056265
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Labelle, J.
(Cornell Univ. Ithaca, NY, United States)
Kelley, M. C.
(Cornell Univ. Ithaca, NY, United States)
Seyler, C. E.
(Cornell University Ithaca, NY, United States)
Date Acquired
August 12, 2013
Publication Date
May 1, 1986
Publication Information
Publication: Journal of Geophysical Research
Volume: 91
ISSN: 0148-0227
Subject Category
Geophysics
Accession Number
86A41003
Funding Number(s)
CONTRACT_GRANT: NSG-6020
CONTRACT_GRANT: N00014-81-K-0018
CONTRACT_GRANT: NSF ATM-84-03044
Distribution Limits
Public
Copyright
Other

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