Bibliography

A case study of ionospheric storm effects in the Chinese sector during the October 2013 geomagnetic storm

In this study, we investigate the ionospheric storm effects in the Chinese sector during 2 October 2013 geomagnetic storm. The TEC map over China sector (1\textdegree\ \texttimes\ 1\textdegree) and eight ionosondes data along the longitude of 110\textdegreeE are used to show significant positive ionospheric phases (enhancements in TEC and ionospheric peak electron density NmF2) in the high-middle latitude region and the negative effects at the low latitude and equatorial region during the storm. A wave structure with periods about 1\textendash2\ h and horizontal speed about 680\ m/s, propagating from the high latitudes to the low latitudes is observed in electron densities within the height region from 200 to 400\ km, which is caused by the combined effects of neutral wind and the large-scale traveling disturbances (LSTIDs). In the low latitude regions, compared with those in the quiet day, the ionospheric peak heights of the F2 layer (hmF2) in the storm day obviously increase accompanying a notably decrease in TEC and NmF2, which might be as a result of the eastward prompt penetration electric field (PPEF) evidenced by the two magnetometers and the subsequent westward disturbance dynamo electric fields (DDEF). The storm-time TEC enhancement mainly occurs in the topside ionosphere, as revealed from the topside TEC, bottomside TEC and GPS TEC.

Mao, Tian; Sun, Lingfeng; Hu, Lianhuan; Wang, Yungang; Wang, Zhijun;

Published by: Advances in Space Research      Published on: 06/2015

YEAR: 2015     DOI: 10.1016/j.asr.2015.05.045

Ionospheric storm; Neutral wind; LSTIDs; PPEF; DDEF

Nighttime F-region morphology in the low and middle latitudes seen from DMSP F15 and TIMED/GUVI

We investigate the seasonal, longitudinal, and altitudinal variations of the FF-region morphology at 2100\textendash2300\ LT in the low- and middle-latitudes using the data collected in August, September, and November of 2003. The topside morphology is investigated using in situ measurements of the O⁺O+ fraction and total ion density by the Defense Meteorological Satellite Program (DMSP) F15 satellite. The morphology of the equatorial ionization anomaly (EIA) near the FF peak altitude is investigated using the OI 135.6-nm radiance maps provided by the Global Ultraviolet Imager (GUVI) on board the Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) satellite. The hemispheric asymmetries of the topside ionosphere at 840\ km in the months near solstices can be characterized by the reduction of the O⁺O+ fraction and ion density in the winter hemisphere compared to those in the summer hemisphere. The minimum O⁺O+ fraction and ion density layers occur around 30^o30o magnetic latitude in the winter hemisphere. During the fall equinox, the hemispheric asymmetries are reversed in the regions of opposite magnetic declinations. From the comparison of the topside morphology with the global wind circulation pattern at 2200\ LT predicted by the Horizontal Wind Model 93 (HWM93) we infer that hemispheric asymmetry of the topside ionosphere is created primarily by the retardation of the downward plasma diffusion in one hemisphere through the field-aligned equatorward winds. The global EIA morphology does not conform to the topside morphology. The complex seasonal-longitudinal variations of the EIA strength and asymmetry are not explained simply by considering the modulation of the FF-layer height by the winds. The magnetic declination is not a useful tool in understanding the global EIA morphology.

Kil, Hyosub; DeMajistre, Robert; Paxton, L.; Zhang, Yongliang;

Published by: Journal of Atmospheric and Solar-Terrestrial Physics      Published on: 09/2006

YEAR: 2006     DOI: 10.1016/j.jastp.2006.05.024

Equatorial ionization anomaly; FF-region plasma distribution; low-latitude ionosphere; Neutral wind