Escape of fast oxygen from the atmosphere during geomagnetic storms
Abstract
Observations have been reported of energetic O+ fluxes (0.7-12 keV with energy fluxes of up to 0.4 erg cm-2 s-1 sr-1) during several magnetic storms. We examine the atmospheric effects to be expected from the precipitation of these fluxes. The fast O+ ions produce fast O atoms through charge exchange and momentum transfer (yielding atomic oxygen emissions that may be as bright as 200 R). The fast oxygen atoms lose their energy largely through momentum transfer collisions with ambient oxygen atoms. This process produces a large shower of low-energy nonthermal oxygen atoms and results in heating of the atmosphere above 200 km. A substantial number of these oxygen atoms have sufficient energy to escape from the atmosphere. If this type of precipitation event occurs frequently enough, the escape mechanism could result in a significant loss of atmospheric oxygen over the lifetime of the earth.
- Publication:
-
Journal of Geophysical Research
- Pub Date:
- December 1974
- DOI:
- 10.1029/JA079i034p05267
- Bibcode:
- 1974JGR....79.5267T
- Keywords:
-
- Atmospheric Physics;
- Atomic Collisions;
- Magnetic Storms;
- Oxygen Ions;
- Atmospheric Chemistry;
- Charge Exchange;
- Energy Transfer;
- Momentum Transfer;
- Oxygen Atoms;
- Particle Collisions;
- Particle Energy;
- Aeronomy: Absorption and scattering of radiation (particles or waves);
- Particles and Fields-Ionosphere: Airglow;
- Particles and Fields-Ionosphere: Particle precipitation;
- Particles and Fields-Magnetosphere: Magnetic storms