Drivers of the hemispheric asymmetry in the low-latitude electron density distribution
Abstract
The hemispheric distribution of the electron density in low latitudes varies with local time, season, altitude, and solar cycle. The combined effects of fountain process and neutral winds are primarily responsible for the variation of the hemispheric plasma distribution. We present the hemispheric asymmetry in the electron density observed by COSMIC, CHAMP,ROCSAT-1, DMSP, GPS TEC, TIMED/GUVI, and ionosonde. The distinguishing features in those observations are the reversal of the hemispheric asymmetry during daytime and the inconsistency of the hemispheric asymmetry between at the F peak height and on the topside. These phenomena are considered to be associated with the promotion and interruption of the equatorial plasma diffusion by neutral winds. By using the SAMI2 model simulation results for various inputs of vertical plasma drifts and neutral winds, we discuss the role of fountain process and neutral winds in the creation the hemispheric asymmetry.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2013
- Bibcode:
- 2013AGUFMSA41B2122K
- Keywords:
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- 2437 IONOSPHERE Ionospheric dynamics;
- 2415 IONOSPHERE Equatorial ionosphere