Title: Current-carrying Production of Nitrogen Oxide NO
Author: P. Nenovski
Affil: Geophysical Institute, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
Email: nenovski@geophys.bas.bg
Abstract:
A current-carrying production of the neutral nitrogen oxide NO that emerges in the E region is considered. A notion is suggested according to which the NO concentration balance is an issue of the condition for divergenceless currents in the E region.
Under geomagnetic activity conditions the large-scale field-aligned currents (FAC) are intensified and grow up to 6.10
Am
.
The NO+ ions having been in equilibrium before the geomagnetic activity, are now neutralizing in the zone of upward large-scale FAC. The thermal electrons in the zone of downward large-scale FAC are in turn able to neutralize the incoming positive charge. A FAC dependent nitrogen atom (N) production rate q(N) is obtained.
A NO production process continues without interruption within certain heights interval where new portions of molecular ions and electrons are arriving. A parameter that prevents the NO production at the maximum Pedersen conductivity height and higher and below the Hall conductivity maximum is straightforwardly derived.
An inclusion of such a FAC driven-like production of N suffices to explain the NO concentration excess frequently observed in the high-latitude E region.
Series of NO concentration profiles that correspond from quiet to strong geomagnetic activity are modeled. Key aeronomic processes in the middle atmosphere regions and possible climate effects depending on the FAC and NO variations at high-latitudes are briefly envisaged.