Electron Scavenging in the Night-Time Mesosphere - A Collection of Empirical Data
Abstract
In the nocturnal lower ionosphere there are always more positive ions than electrons and the difference for charge neutrality is generally ascribed to negative ions. The absence of direct sunlight and atomic oxygen allows to describe the relation between electrons, positive and negative ions in a very simple way, essentially only depending on the ratio between attachment rate of electrons to molecules and ion-ion recombination. From 27 sounding rocket flights we find that this ratio scatters by more than two orders of magnitude which can neither be explained by uncertainties of the attachment rate, nor by the ion-ion recombination. The ratio does, however, vary largely as one would intuitively expected as a function of temperature, ionization, solar zenith angle and indeed the phase of the moon. But to explain the huge scatter in the data we suggested that electron scavenging by particles larger than molecules such as meteoric smoke may reconsile the observations.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2008
- Bibcode:
- 2008AGUFMSA41A1550F
- Keywords:
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- 0305 Aerosols and particles (0345;
- 4801;
- 4906);
- 0335 Ion chemistry of the atmosphere (2419;
- 2427);
- 0340 Middle atmosphere: composition and chemistry;
- 2407 Auroral ionosphere (2704)