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Modeling the equatorial and low‐latitude ionospheric response to an intense X‐class solar flare
(American Geophysical Union, 2015-03-11)
We have investigated the ionospheric response close to the subsolar point in South America due to the strong solar flare (X2.8) that occurred on 13 May 2013. The present work discusses the sudden disturbances in the D ...
Critical frequencies of the ionospheric F1 and F2 layers during the last four solar cycles: Sunspot group type dependencies
(Elsevier, 2018-06)
The long term solar activity dependencies of ionospheric F1 and F2 regions’ critical frequencies (f0F1 and f0F2) are analyzed for the last four solar cycles (1976–2015). We show that the ionospheric F1 and F2 regions have ...
Electrodynamics in the low and middle latitude ionosphere: a tutorial
(Elsevier, 2004-03-24)
Electric fields in the low and middle latitude ionosphere result from currents driven internally by neutral winds and gravity, and externally by applied potentials. The resulting internal electric polarization fields arise ...
Inverting ionospheric radio occultation measurements using maximum entropy
(American Geophysical Union, 2007-08-18)
Practical aspects of the inversion of ionospheric radio occultation data using the Abel transform and its inverse are discussed. The linear inverse transform exhibits poor error propagation characteristics, producing ...
Numerical study of the generation and propagation of ultralow-frequency waves by artificial ionospheric F region modulation at different latitudes
(European Geosciences Union, 2016-09-21)
Powerful high-frequency (HF) radio waves can be used to efficiently modify the upper-ionospheric plasmas of the F region. The pressure gradient induced by modulated electron heating at ultralow-frequency (ULF) drives a ...
Daytime plasma drifts in the equatorial lower ionosphere
(American Geophysical Union, 2015-10-19)
We have used extensive radar measurements from the Jicamarca Observatory during low solar flux periods to study the quiet time variability and altitudinal dependence of equatorial daytime vertical and zonal plasma drifts. ...
Response of the topside and bottomside ionosphere at low and middle latitudes to the October 2003 superstorms
(American Geophysical Union, 2015-07-14)
Ionospheric observations from the ground‐based GPS receiver network, CHAMP and GRACE satellites and ionosondes were used to examine topside and bottomside ionospheric variations at low and middle latitudes over the Pacific ...
Contribution of the topside and bottomside ionosphere to the total electron content during two strong geomagnetic storms
(American Geophysical Union, 2016-02-12)
In this study, the ionospheric observations from ionosondes, GPS receivers, and incoherent scatter radars (ISR) at low and middle latitudes were used to investigate the contribution of the bottomside and topside ionosphere ...
Plasma drifts and polarization electric fields associated with TID‐like disturbances in the low‐latitude ionosphere: C/NOFS observations
(American Geophysical Union, 2016-01-13)
Medium‐scale traveling ionospheric disturbances are often observed at the magnetically conjugate points in the nighttime midlatitude ionosphere. It has been suggested that gravity waves disturb the ionosphere and induce ...
Unusual nighttime impulsive foF2 enhancement below the southern anomaly crest under geomagnetically quiet conditions
(American Geophysical Union, 2011-12)
An unusual nighttime impulsive electron density enhancement was observed on 6 March 2010 over a wide region of South America, below the southern crest of the equatorial anomaly, under low solar activity and quiet geomagnetic ...