Ionospheric Dynamics Effects on the Ionospheric Magnesium-Iron Ion Concentration Ratios
Abstract
Sounding rocket and satellite ion composition measurements show that the meteoric Fe+ concentration typically exceeds that of Mg + in the main meteor ionization layer and above. This is a puzzle because the assumed source of the metal ions is the sporadic background of infalling meteoroids, which are on average chondritic in nature and hence should deposit a higher portion of Mg in the atmosphere than Fe. A more detailed investigation the ionosphere measurements revealed that the ratio varies from measurement to measurement with Mg + and Fe + often switching dominance roles, although on average Fe + dominates. Possible sources for the relative variations between the two species include differential ablation, species-dependent ion-neutral chemical processes, non-isotropic interplanetary particle populations and neutral wind and electrodynamic influences. We will discuss the observations and show that ionospheric dynamics and electrodynamic processes can play an important role.
- Publication:
-
AGU Spring Meeting Abstracts
- Pub Date:
- May 2001
- Bibcode:
- 2001AGUSM..SA31A04G
- Keywords:
-
- 0355 Thermosphere--composition and chemistry;
- 2415 Equatorial ionosphere;
- 2423 Ionization mechanisms;
- 2437 Ionospheric dynamics;
- 2443 Midlatitude ionosphere