Aerosol and Clouds
Relationship of electric field and charged particle density fluctuations to air turbulence in the mesosphere
Article first published online: 17 OCT 2007
Copyright 2007 by the American Geophysical Union.
Journal of Geophysical Research: Atmospheres (1984–2012)
Volume 112, Issue D20, 27 October 2007
How to Cite
2007), Relationship of electric field and charged particle density fluctuations to air turbulence in the mesosphere, J. Geophys. Res., 112, D20203, doi:10.1029/2007JD008412.(
- Issue published online: 17 OCT 2007
- Article first published online: 17 OCT 2007
- Manuscript Accepted: 22 JUN 2007
- Manuscript Revised: 14 MAY 2007
- Manuscript Received: 12 JAN 2007
- charged aerosols;
- noctilucent clouds
 A theoretical model is developed that is applicable to the electric field fluctuations that arise in the polar summer mesosphere as a result of the coupling of the charged species to the neutral air turbulence. The motions of electrons, ions, and charged aerosol particles are described as harmonic oscillators both driven and damped by the drag force exerted by the neutral air. The relative fluctuations in the ion density are found to be nearly the same as those in the neutral air as a consequence of the ions' high-momentum transfer relaxation frequency. The aerosol density fluctuations follow those of the neutral air at frequencies below their relaxation frequency, which is in the acoustic range. The electrons move primarily in response to the electric force to partially cancel the net charge density of ions and aerosol particles except at wavelengths shorter than the Debye length. Electric field and charge density fluctuations are calculated for several sets of conditions. In “bite-out” regions in which the electron density is reduced as a consequence of attachment to the aerosol particles the electric field fluctuations are found to be enhanced, which is consistent with observations.