Thermospheric composition and the positive phase of an ionospheric storm
Abstract
The ionospheric storm concept developed by the authors related both positive and negative phases of the storm to variations of the thermospheric composition ([O]/[N2]-ratio) at F2-layer heights. During the negative phase this variation is due to Joule heating, whereas for the positive phase, in the scope of the concept, two mechanisms are considered: the increase of [O]/[N2]-ratio in the circulation pattern, moving from the dayside cusp through polar cap to the nightside thermosphere, and the lifting up of the F2-layer peak due to disturbed meridional winds into the region with weaker recombination. It is shown that the behaviour of the foF2 during the storm might be described using the position (geomagnetic latitude) for each particular moment of the auroral oval and of the dayside cusp as indicators of the activity of two principal mechanisms in described conditions.
- Publication:
-
Advances in Space Research
- Pub Date:
- October 1992
- DOI:
- 10.1016/0273-1177(92)90475-D
- Bibcode:
- 1992AdSpR..12j.257D
- Keywords:
-
- Atmospheric Circulation;
- Electromagnetic Interference;
- F 2 Region;
- Ionospheric Storms;
- Thermosphere;
- Auroras;
- Geomagnetism;
- Ionosondes;
- Nitrogen;
- Oxygen Atoms;
- Polar Regions;
- Geophysics