Hei, Matthew A.Valladares, Cesar E.2018-11-072018-11-072009-04-07Hei, M. A., & Valladares, C. E. (2009). The November 2004 superstorm: Comparison of low-latitude TEC observations with LLIONS model results.==$Journal of Atmospheric and Solar-Terrestrial Physics, 72$==(4), 334-343. https://doi.org/10.1016/j.jastp.2009.03.025http://hdl.handle.net/20.500.12816/3364We investigate the effects of penetration electric fields, meridional thermospheric neutral winds, and composition perturbation zones (CPZs) on the distribution of low-latitude plasma during the 7–11 November 2004 geomagnetic superstorm. The impact on low-latitude plasma was assessed using total electron content (TEC) measurements from a latitudinally distributed array of ground-based GPS receivers in South America. Jicamarca Radio Observatory incoherent scatter radar measurements of vertical E×B drift are used in combination with the Low-Latitude IONospheric Sector (LLIONS) model to examine how penetration electric fields and meridional neutral winds shape low-latitude TEC. It is found that superfountain conditions pertain between ∼1900 and 2100 UT on 9 November, creating enhanced equatorial ionization anomaly (EIA) crests at ±20° geomagnetic latitude. Large-amplitude and/or long-duration changes in the electric field were found to produce significant changes in EIA plasma density and latitudinal location, with a delay time of ∼2–2.5 h. Superfountain drifts were primarily responsible for EIA TEC levels; meridional winds were needed only to create hemispherical crest TEC asymmetries. The [O/N2] density ratio (derived from the GUVI instrument, flown on the TIMED satellite) and measurements of total atmospheric density (from the GRACE satellites), combined with TEC measurements, yield information regarding a likely CPZ that appeared on 10 November, suppressing TEC for over 16 h.application/pdfenginfo:eu-repo/semantics/restrictedAccessEIACPZSuperstormSuperfountainGPSTECinfo:eu-repo/semantics/articlehttp://purl.org/pe-repo/ocde/ford#1.05.01Journal of Atmospheric and Solar-Terrestrial Physicshttps://doi.org/10.1016/j.jastp.2009.03.025