Satellite In Situ Electron Density Observations of the Midlatitude Storm Enhanced Density on the Noon Meridional Plane in the F Region During the 20 November 2003 Magnetic Storm

Abstract

Ionospheric storm enhanced density (SED) has been extensively investigated using total electron content deduced from GPS ground and satellite‐borne receivers. However, dayside in situ electron density measurements have not been analyzed in detail for SEDs yet. We report in situ electron density measurements of a SED event in the Northern Hemisphere (NH) at the noon meridian plane measured by the Challenging Minisatellite Payload (CHAMP) polar‐orbiting satellite at about 390 km altitude during the 20 November 2003 magnetic storm. The CHAMP satellite measurements render rare documentation about the dayside SED's life cycle at a fixed magnetic local time (MLT) through multiple passes. Solar wind drivers triggered the SED onset and controlled its lifecycle through its growth and retreat phases. The SED electron density enhancement extended from the equatorial ionization anomaly to the noon cusp. The midlatitude electron density increased to a maximum at the end of the growth phase. Afterward, the dayside SED region retreated gradually to lower magnetic latitudes. The observations showed a hemisphere asymmetry, with the NH electron density exhibiting a more significant enhancement. The simulations using the Thermosphere Ionosphere Electrodynamic General Circulation model show a good agreement with the CHAMP observations. The simulations indicate that the dayside midlatitude electron density enhancement has a complicated dependence on vertical ion drift, neutral wind, magnetic latitude, MLT, and the height of the F2 layer. Finally, we discuss the notion of using the mean cross‐polar cap electric field as a proxy for assessing the effects of solar wind drivers on producing midlatitude electron density enhancement.

Investigation of the Southern Hemisphere Mid‐High Latitude Thermospheric ∑O/N2 Responses to the Space‐X Storm

“…∑O/N 2 can be used to represent the variations of thermosphere composition due to geomagnetic disturbances (Burns et al., 1995; Cai et al., 2020; Cai, Burns, Wang, Qian, Solomon, et al., 2021; Cai, Burns, Wang, Qian, Pedatella, et al., 2021; Crowley et al., 2006; Kil et al., 2011; Meier et al., 2005; Y. Zhang et al., 2003). Moreover, ∑O/N 2 is also crucial for understanding the ionosphere responses to geomagnetic disturbances (Aa et al., 2022; C. S. Lin et al., 2022; Liou et al., 2005; Lu et al., 2012; Meier et al., 2005; Verkhoglyadova et al., 2017; Zhai, Cai, et al., 2023; Zhai, Tang, et al., 2023; Y. Zhang et al., 2003) since it reflects the production and loss of the ionospheric F‐region plasma (Rishbeth, 1998). Additionally, O and N 2 are two of the major components of the thermosphere, influencing the total mass density of the thermosphere, which is important for monitoring and predicting the drag force of low‐Earth‐orbiting satellites (Dietrich et al., 2022).…”

“…ionosphere responses to geomagnetic disturbances (Aa et al, 2022;C. S. Lin et al, 2022;Liou et al, 2005;Lu et al, 2012;Meier et al, 2005;Verkhoglyadova et al, 2017;Zhai, Cai, et al, 2023;Zhai, Tang, et al, 2023; since it reflects the production and loss of the ionospheric F-region plasma (Rishbeth, 1998).…”

Investigation of the Post‐Sunset Extra Electron Density Peak Poleward of the Equatorial Ionization Anomaly Southern Crest

“…Observations have shown that extra latitudinal peaks of electron densities sometimes occur poleward of the EIA crests. During geomagnetic storms, the storm‐enhanced electron density can occur at mid‐latitudes to form third or even fourth electron density latitudinal peaks relative to the EIA crests at certain times (Coster et al., 2016; Horvath & Lovell, 2010; Lin et al., 2022). During geomagnetically quiet times, there are also extra electron density peaks in the mid‐latitudes called mid‐latitude enhancement (Astafyeva et al., 2016; Jiang et al., 2020; Li et al., 2018; Luan et al., 2008; Maruyama et al., 2016; Rajesh et al., 2016; Xiong et al., 2019; Zhong et al., 2019).…”

Investigation of the ΣO/N2 Depletion With Latitudinally Tilted Equatorward Boundary Observed by GOLD During the Geomagnetic Storm on April 20, 2020

“…The least uncertainty in ∑O/N 2 occurs at this N 2 depth (Correira et al., 2021; Strickland et al., 1995). Additionally, ∑O/N 2 is also important for understanding the ionosphere responses to geomagnetic disturbances (Aa et al., 2022; Crowley et al., 2006; Lin et al., 2022; Lu et al., 2012) since it reflects the production and loss of ionosphere F‐region plasma (Rishbeth, 1998).…”