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

Abstract

Ionospheric equatorial ionization anomaly (EIA) is a phenomenon in the F layer with two electron density crests located at about ±15° magnetic latitudes and a density trough in-between (Appleton, 1946). EIA is produced during the daytime when upward E × B drifts uplift the plasma to higher altitudes of low chemical recombination rate. Numerous studies have been carried out to investigate the behavior of EIA by using data from ionosondes (Rishbeth, 2000), total electron content (TEC) maps from ground-based GPS receivers (

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

“…The GOLD Far Ultraviolet imager flies onboard the SES-14 telecommunications satellite, which was launched on 25 January 2018 to the geostationary orbit at 47.5 𝐴𝐴 • W (Eastes et al, 2017). GOLD measures the thermospheric/ionospheric airglow emissions from 134 to 162 nm with a spectral resolution of 0.2 nm during daytime (Eastes et al, 2020) and with a spectral resolution of 0.4 nm at nighttime (Cai et al, 2022a(Cai et al, , 2022bEastes et al, 2019) (Yu et al, 2022). In this study, GOLD observed 𝐴𝐴 Σ O/N 2 in the Northern Hemisphere (NH) with a spatial resolution of 1° × 1° on DOY 110 and 111 are utilized.…”

“…The GOLD Far Ultraviolet imager flies onboard the SES‐14 telecommunications satellite, which was launched on 25 January 2018 to the geostationary orbit at 47.5$${}^{\circ}$$W (Eastes et al., 2017). GOLD measures the thermospheric/ionospheric airglow emissions from 134 to 162 nm with a spectral resolution of 0.2 nm during daytime (Eastes et al., 2020) and with a spectral resolution of 0.4 nm at nighttime (Cai et al., 2022a, 2022b; Eastes et al., 2019). The daytime OI 135.6 nm and N 2 LBH bands (140–150 nm) are utilized to derive $${\Sigma}$$O/N 2 , of which images are in the same regions between 120$${}^{\circ}$$W and 20$${}^{\circ}$$E, 60$${}^{\circ}$$S and 60$${}^{\circ}$$N from 6:10 to 22:40 UT every day (Yu et al., 2022).…”

Hemispherically Asymmetric Evolution of Nighttime Ionospheric Equatorial Ionization Anomaly in the American Longitude Sector

“…The recent Global‐scale Observation of Limb and Disk (GOLD) mission provides nighttime F layer peak electron densities (NmF2) from 2‐D synoptic observations of OI 135.6 nm emission radiance, making it possible to advance nighttime ionosphere studies that resolve both temporal and spatial variations (Aa et al., 2022; Cai, Qian, et al., 2022; Cai et al., 2020, 2021). Cai et al.…”

Mid‐Latitude Ionospheric Response to a Weak Geomagnetic Activity Event During Solar Minimum

“…It should be noted that the density of O + ions is almost equal to the electron density (Ne) in the ionosphere F2 region. The O + and electron densities in the ionosphere F2 region are determined by the following equation (Cai et al, 2022a(Cai et al, , 2022bJ. Liu, Wang, Burns, Solomon, et al, 2016)…”