Bibliography

Notice:

Clicking on the title will open a new window with all details of the bibliographic entry.
Clicking on the DOI link will open a new window with the original bibliographic entry from the publisher.
Clicking on a single author will show all publications by the selected author.
Clicking on a single keyword, will show all publications by the selected keyword.

Found 18 entries in the Bibliography.

Showing entries from 1 through 18

2021

The nighttime ionospheric response and occurrence of equatorial plasma irregularities during geomagnetic storms: a case study

Recent studies revealed that the long-lasting daytime ionospheric enhancements of Total Electron Content (TEC) were sometimes observed in the Asian sector during the recovery phase of geomagnetic storms (e.g., Lei (J Geophys Res Space Phys 123: 3217–3232, 2018), Li (J Geophys Res Space Phys 125: e2020JA028238, 2020). However, they focused only on the dayside ionosphere, and no dedicated studies have been performed to investigate the nighttime ionospheric behavior during such kinds of storm recovery phases. In this study, we focused on two geomagnetic storms that happened on 7–8 September 2017 and 25–26 August 2018, which showed the prominent daytime TEC enhancements in the Asian sector during their recovery phases, to explore the nighttime large-scale ionospheric responses as well as the small-scale Equatorial Plasma Irregularities (EPIs). It is found that during the September 2017 storm recovery phase, the nighttime ionosphere in the American sector is largely depressed, which is similar to the daytime ionospheric response in the same longitude sector; while in the Asian sector, only a small TEC increase is observed at nighttime, which is much weaker than the prominent daytime TEC enhancement in this longitude sector. During the recovery phase of the August 2018 storm, a slight TEC increase is observed on the night side at all longitudes, which is also weaker than the prominent daytime TEC enhancement. For the small-scale EPIs, they are enhanced and extended to higher latitudes during the main phase of both storms. However, during the recovery phases of the first storm, the EPIs are largely enhanced and suppressed in the Asian and American sectors, respectively, while no prominent nighttime EPIs are observed during the second storm recovery phase. The clear north–south asymmetry of equatorial ionization anomaly crests during the second storm should be responsible for the suppression of EPIs during this storm. In addition, our results also suggest that the dusk side ionospheric response could be affected by the daytime ionospheric plasma density/TEC variations during the recovery phase of geomagnetic storms, which further modulates the vertical plasma drift and plasma gradient. As a result, the growth rate of post-sunset EPIs will be enhanced or inhibited.

Wan, Xin; Xiong, Chao; Gao, Shunzu; Huang, Fuqing; Liu, Yiwen; Aa, Ercha; Yin, Fan; Cai, Hongtao;

Published by: Satellite Navigation Published on: nov

YEAR: 2021 DOI: 10.1186/s43020-021-00055-x

Equatorial plasma irregularity; Geomagneitc storm; Ionospheric response; longitudinal variations; Storm recovery phase

A Synoptic-Scale Wavelike Structure in the Nighttime Equatorial Ionization Anomaly

Both ground- and satellite-based airglow imaging have significantly contributed to understanding the low-latitude ionosphere, especially the morphology and dynamics of the equatorial ionization anomaly (EIA). The NASA Global-scale Observations of the Limb and Disk (GOLD) mission focuses on far-ultraviolet airglow images from a geostationary orbit at 47.5°W. This region is of particular interest at low magnetic latitudes because of the high magnetic declination (i.e., about -20°) and proximity of the South Atlantic magnetic anomaly. In this study, we characterize an exciting feature of the nighttime EIA using GOLD observations from October 5, 2018 to June 30, 2020. It consists of a wavelike structure of a few thousand kilometers seen as poleward and equatorward displacements of the EIA-crests. Initial analyses show that the synoptic-scale structure is symmetric about the dip equator and appears nearly stationary with time over the night. In quasi-dipole coordinates, maxima poleward displacements of the EIA-crests are seen at about ± 12° latitude and around 20 and 60° longitude (i.e., in geographic longitude at the dip equator, about 53°W and 14°W). The wavelike structure presents typical zonal wavelengths of about 6.7 × 103 km and 3.3 × 103 km. The structure s occurrence and wavelength are highly variable on a day-to-day basis with no apparent dependence on geomagnetic activity. In addition, a cluster or quasi-periodic wave train of equatorial plasma depletions (EPDs) is often detected within the synoptic-scale structure. We further outline the difference in observing these EPDs from FUV images and in situ measurements during a GOLD and Swarm mission conjunction.

Rodríguez-Zuluaga, J.; Stolle, C.; Yamazaki, Y.; Xiong, C.; England, S.;

Published by: Earth and Space Science Published on:

YEAR: 2021 DOI: 10.1029/2020EA001529

equatorial plasma bubbles; Equatorial ionization anomaly; Equatorial ionosphere; forcing from below; wave structure

Interaction Between an EMSTID and an EPB in the EIA Crest Region Over China

Few observations investigated the interaction between an electrical medium-scale traveling ionospheric disturbance (EMSTID) and an equatorial plasma bubble (EPB). This paper presents another interaction between a southwestward propagating EMSTID and an eastward drifting EPB in the equatorial ionization anomaly (EIA) crest region of China. When the EMSTID and the EPB touched each other, several depletions of the EMSTID (EPB) showed the eastward (westward) velocity disturbances of the EPB (EMSTID) depletions. Besides, phase elongations of the EPB depletions contrarotated as the EMSTID propagated southwestward. However, of important finding is that the interaction of the EMSTID and the EPB could have polarized one depletion of the postmidnight EPB that should have become a fossilized bubble. Inside that polarized EPB depletion were meter-scale irregularities that caused activated radar echoes and enhanced ranged spread F (RSF). The interaction occurred in descending ionosphere and the lower density regions got filled up with an enhanced density plasma. We propose that the EMSTID and the EPB could have electrically coupled with each other, causing an enhanced polarization electric field (PEF) that polarized that EPB depletion; the E × B gradient drift instability (Kelley, 1989) could have caused the meter-scale irregularities when that enhanced PEF was imposed on that reactivated EPB depletion surrounded by that enhanced density plasma. This study provides observational evidence that how an electrical couple of EMSTID and EPB events can activate a postmidnight EPB depletion that should become a fossilized structure.

Sun, Longchang; Xu, JiYao; Zhu, Yajun; Xiong, Chao; Yuan, Wei; Wu, Kun; Hao, Yongqiang; Chen, Gang; Yan, Chunxiao; Wang, Zhihua; Zhao, Xiukuan; Luo, Xiaomin;

Published by: Journal of Geophysical Research: Space Physics Published on:

YEAR: 2021 DOI: 10.1029/2020JA029005

airglow; EIA crest region; Interaction between MSTID and EPB; Nighttime plasma density enhancement; Polarization of postmidnight EPB; VHF radar echoes and range spread F

2020

Relationship between large-scale ionospheric field-aligned currents and electron/ion precipitations: DMSP observations

In this study, we have derived field-aligned currents (FACs) from magnetometers onboard the Defense Meteorological Satellite Project (DMSP) satellites. The magnetic latitude versus

Xiong, Chao; Stolle, Claudia; Alken, Patrick; Rauberg, Jan;

Published by: Earth, Planets and Space Published on:

YEAR: 2020 DOI: 10.1186/s40623-020-01286-z

Comparison of electron density and temperature from the CSES satellite with other space-borne and ground-based observations

In this paper we provide a comprehensive comparison of in situ electron density (Ne) and temperature (Te) measured by Langmuir probe (LAP) on board the China Seismo‐

Yan, Rui; Zhima, Zeren; Xiong, Chao; Shen, Xuhui; Huang, Jianping; Guan, Yibing; Zhu, Xinghong; Liu, Chao;

Published by: Journal of Geophysical Research: Space Physics Published on:

YEAR: 2020 DOI: 10.1029/2019JA027747

A mesoscale wave-like structure in the nighttime equatorial ionization anomaly

Both ground-and satellite-based airglow imaging have significantly contributed to our understanding of the low-latitude ionosphere, especially of the morphology and dynamics of the

iguez-Zuluaga, Juan; Stolle, Claudia; Yamazaki, Yosuke; Xiong, Chao; England, Scott;

Published by: Earth and Space Science Open Archive ESSOAr Published on:

YEAR: 2020 DOI: 10.1002/essoar.10504705.1

2019

An Opposite Response of the Low-Latitude Ionosphere at Asian and American Sectors During Storm Recovery Phases: Drivers From Below or Above

n this study, we focus on the recovery phase of a geomagnetic storm that happened on 6\textendash11 September 2017. The ground-based total electron content data, as well as the F region in situ electron density, measured by the Swarm satellites show an interesting feature, revealing at low and equatorial latitudes on the dayside ionosphere prominent positive and negative responses at the Asian and American longitudinal sectors, respectively. The global distribution of thermospheric O/N₂ ratio measured by global ultraviolet imager on board the Thermosphere, Ionosphere, Mesosphere Energetics and Dynamics satellite cannot well explain such longitudinally opposite response of the ionosphere. Comparison between the equatorial electrojet variations from stations at Huancayo in Peru and Davao in the Philippines suggests that the longitudinally opposite ionospheric response should be closely associated with the interplay of E region electrodynamics. By further applying nonmigrating tidal analysis to the ground-based total electron content data, we find that the diurnal tidal components, D0 and DW2, as well as the semidiurnal component SW1, are clearly enhanced over prestorm days and persist into the early recovery phase, indicating the possibility of lower atmospheric forcing contributing to the longitudinally opposite response of the ionosphere on 9\textendash11 September 2017.

Xiong, Chao; Lühr, Hermann; Yamazaki, Yosuke;

Published by: Journal of Geophysical Research: Space Physics Published on: 07/2019

YEAR: 2019 DOI: 10.1029/2019JA026917

2016

Scale analysis of equatorial plasma irregularities derived from Swarm constellation

In this study, we investigated the scale sizes of equatorial plasma irregularities (EPIs) using measurements from the Swarm satellites during its early mission and final constellation

Xiong, Chao; Stolle, Claudia; Lühr, Hermann; Park, Jaeheung; Fejer, Bela; Kervalishvili, Guram;

Published by: Earth, Planets and Space Published on:

YEAR: 2016 DOI: 10.1186/s40623-016-0502-5

2013

East-west differences in F -region electron density at midlatitude: Evidence from the Far East region

The global configuration of the geomagnetic field shows that the maximum east-west difference in geomagnetic declination of northern middle latitude lies in the US region (~32\textdegree), which produces the significant ionospheric east-west coast difference in terms of total electron content first revealed by Zhang et al. (2011). For verification, it is valuable to investigate this feature over the Far East area, which also shows significant geomagnetic declination east-west gradient but smaller (~15\textdegree) than that of the US. The current study provides evidence of the longitudinal change supporting the thermospheric zonal wind mechanism by examining the climatology of peak electron density (NmF2), electron density (Ne) of different altitudes in the Far East regions with a longitude separation of up to 40\textendash60\textdegree based on ground ionosonde and space-based measurements. Although the east-west difference (R_ew) over the Far East area displays a clear diurnal variation similar to the US feature, that is negative R_ew (West Ne \> East Ne) in the noon and positive at evening-night, the observational results reveal more differences including: (1) The noontime negative R_ew is most pronounced in April\textendashJune while in the US during February\textendashMarch. Thus, for the late spring and summer period negative R_ew over the Far East region is more significant than that of the US. (2) The positive R_ew at night is much less evident than in the US, especially without winter enhancement. (3) The magnitude of negative R_ew tends to enhance toward solar maximum while in the US showing anticorrelation with the solar activity. The altitude distribution of pronounced negative difference (300\textendash400 km) moves upward as the solar flux increases and hence produces the different solar activity dependence at different altitude. The result in the paper is not simply a comparison corresponding to the US results but raises some new features that are worth further studying and improve our current understanding of ionospheric longitude difference at midlatitude.

Zhao, Biqiang; Wang, Min; Wang, Yungang; Ren, Zhipeng; Yue, Xinan; Zhu, Jie; Wan, Weixing; Ning, Baiqi; Liu, Jing; Xiong, Bo;

Published by: Journal of Geophysical Research: Space Physics Published on: 01/2013

YEAR: 2013 DOI: 10.1029/2012JA018235

geomagnetic declination; longitudinal variation; midlatitude ionosphere

Nonmigrating tidal signatures in the magnitude and the inter-hemispheric asymmetry of the equatorial ionization anomaly

Based on nine years of observations from the satellites CHAMP and GRACE the tidal signatures in the magnitude and the inter-hemisphere asymmetry of the equatorial ionization anomaly (EIA) have been investigated in this study. The EIA magnitude parameters show longitudinal wavenumber 4 and 3 (WN4/WN3) patterns during the months around August and December, respectively, while for different EIA parameters the contributions of the various tidal parameters are different. For the crest- to-trough ratio (CTR) the dominating nonmigrating tidal component contributing to WN4 is DE3 during the months around August, while during the months around December solstice the stationary planetary wave, SPW3, takes a comparable role to DE2 in contributing to WN3. For the apex height index (ApexHC) of the EIA fluxtube the stationary planetary waves, SPW4/SPW3, exceed the amplitudes of DE3/DE2 taking the leading role in causing the longitudinal WN4/WN3 patterns. During the\ months around December solstice the SW3 tide is prominent in both CTR and ApexHC. SW3 shows a strong dependence on the solar flux level, while it is hardly dependent on magnetic activity. For the EIA interhemispheric asymmetry only WN1 and WN2 longitudinal patterns can be seen. During June solstice months the pattern can be explained by stationary planetary waves SPW1 and SPW2. Conversely, around December solstice months longitudinal features exhibit some local time evolution,\ in particular the diurnal nonmigrating tide D0 takes the leading role.

Xiong, C.; Lühr, H.;

Published by: Annales Geophysicae Published on: 01/2013

YEAR: 2013 DOI: 10.5194/angeo-31-1115-2013

Atmospheric dynamics; Equatorial ionosphere; Ionosphere; ionosphere\textendashatmosphere interactions. Meteorology

Determining the equatorward and poleward boundaries of the auroral oval from CHAMP field-aligned currents signatures

IRI peak E-region electron density with assimilated auroral NmE from GUVI auroral model.

Xiong, Chao; Lühr, Hermann; Ritter, Patricia;

Published by: Published on:

YEAR: 2013 DOI:

2012

A simulation study for the couplings between DE3 tide and longitudinal WN4 structure in the thermosphere and ionosphere

Wan, W.; Ren, Z.; Ding, F.; Xiong, J.; Liu, L.; Ning, B.; Zhao, B.; Li, G.; Zhang, M.-L.;