Statistical Behavior of the Longitudinal Variations of the Evening Topside Mid‐Latitude Trough Position in both Northern and Southern Hemispheres

et al. 2021

Space Weather

Self Cite

• A global model of Ne profile in F region ionosphere was constructed based on the α-Chapman function • The model gives 3-D Ne as well as five key parameters of Ne profile, including NmF2, hmF2, Hm and its change rates with height • The model reasonably reproduces the equatorial ionization anomaly and midlatitude trough Accepted Article This article has been accepted for publication and undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record. Please cite this article as

Section: Accepted Articlementioning

confidence: 97%

“…NmF2 shows (1) latitude structure: EIA, nighttime midlatitude trough around the subauroral region in the northern hemisphere (Yang et al, 2018), and midlatitude band structure (Zhong et al, 2019);…”

Section: Validity At Climatological Descriptionmentioning

confidence: 99%

A Global Empirical Model of Electron Density Profile in the F Region Ionosphere Basing on COSMIC Measurements

et al. 2021

Space Weather

Self Cite

“…Yang N et al (2018) statistically analyzed the mid‐latitude trough position in the Northern and Southern hemispheres based on ion density data from the Defense Meteorological Satellite Program (DMSP) satellites in 1996–2016. The longitudinal variation of the trough position has significant seasonal, solar activity, and geomagnetic activity dependences.…”

Section: Ionospheric Structures and Climatologymentioning

confidence: 99%

Recent ionospheric investigations in China (2018–2019)

Earth and Planetary Physics

Wan

2020

Self Cite

Key Points:Ionospheric observations have continuously accumulated with increasing GNSS receivers being installed q Studies of ionospheric climatology and space weather highlight new physical understanding q Study of ionospheric irregularities/scintillations reports interesting features q Abstract: Since the release of the 2018 National Report of China on ionospheric research ( Liu LB and Wan WX, 2018) to the Committee on Space Research (COSPAR), scientists from Mainland China have made many new fruitful investigations of various ionospheric-related issues. In this update report, we briefly introduce more than 130 recent reports ( [2018][2019]. The current report covers the following topics: ionospheric space weather, ionospheric structures and climatology, ionospheric dynamics and couplings, ionospheric irregularity and scintillation, modeling and data assimilation, and radio wave propagation in the ionosphere and sounding techniques. ΔV para (m/s) SYM-H (nT) V para (m/s) V para (m/s) ΔV para (m/s) Figure 2. (a) The SYM-H index on 13-17 July 2012. The blue line marks the storm onset (at 06:42 UT on 15 July); yellow and gray areas indicate the 24-hour storm-time and 24-hour quiet-time intervals. (b) The blue dots denote the storm-time equatorial field-aligned plasma drifts observed by C/NOFS with red curve representing median and red lines denoting upper and lower quartile values. (c) Same as panel (b), but for the 24-hour quiet time interval. (d) The difference between (b) and (c). (e-h) Same as panels (a-d), but for the case on 7-11 July 2012 where the 24-hour quiet and storm intervals start at 04:12 UT on 7 and 9 July, respectively, after Zhang R et al. (2018). Earth and Planetary Physics

“…Liu et al (2015) used the CHAMP (CHAllenging Minisatellite Payload) electron density measurements (2000–2009) to investigate the position of the trough minimum, and they found a significant longitudinal dependence of the trough minimum around midnight under geomagnetic quiet condition. Yang et al (2018) further statistically analyzed the longitudinal variation of MIT position in both northern (near 1900 MLT) and southern hemispheres (near 2100 MLT), based on the in situ ion density measurements from the DMSP (Defense Meteorological Satellite Program) satellites during 1996–2016. Their results showed significant difference in the longitudinal variation of the trough position between two hemispheres during premidnight hours.…”

Section: Introductionmentioning

confidence: 99%

Morphology Evolution of the Midlatitude Ionospheric Trough in Nighttime Under Geomagnetic Quiet Conditions

Xiong

2020

JGR Space Physics

The dynamics and climatology of midlatitude trough minimum have been widely investigated. However, the detailed magnetic local time (MLT) evolution of the trough walls (both equatorward and poleward) has not been well addressed. In this study, we used nearly 10‐year Planar Langmuir Probe (PLP) data from the CHAMP satellite to investigate how the location and shape of midlatitude trough evolve during night hours. We find that (1) the trough equatorward wall experiences an obvious equatorward extension in the premidnight sector, with steepness rapidly decreasing during the same local time sector; (2) the trough equatorward wall is as steep as poleward wall in the dusk sector; and (3) the trough poleward wall shows no remarkable change during the whole nighttime, except for a weakly reduced width and a slightly enhanced steepness near midnight. We suggest that the rapid extension of the equatorward wall in the premidnight sector is closely related to the plasma equatorward movement caused by the neutral winds. The rapid decrease of the steepness of the equatorward wall in the premidnight sector is not only influenced by its own width expansion but possibly also related to the upward plasma drift caused by neutral winds. The trough minimum and equatorward/poleward boundaries are found located at slightly higher magnetic latitude during equinoxes than that during solstice seasons.