Bibliography

Correlations Between Giant Undulations and Plasmapause Configurations

In this letter, we report the correlations between giant undulations (GUs) and plasmapause (PP) configurations based on GUs images and corresponding PP crossings of satellites between 2005 and 2019. Typically, GUs occur when the plasmasphere is eroded to form a thin and sharp PP during the storm main phase and early recovery phase. The thicknesses of the PP are usually comparable with the azimuthal wavelengths of the GUs and are smaller than the radial amplitudes of the GUs. The amplitudes and wavelengths are quasi-proportional to the thicknesses of the PP and are inversely quasi-proportional to the ion density gradients around the PP. The radial centers of GUs are typically aligned with the PP surfaces and their radial geocentric locations show positive correlations for different geomagnetic storms. These results would provide both physical insights and model constrains on the magnetosphere-plasmasphere-ionosphere energy coupling and the generation mechanisms of the GUs and plasmapause surface waves.

Zhou, Yi-Jia; He, Fei; Yao, Zhong-Hua; Wei, Yong; Zhang, Xiao-Xin; Zhang, Yong-Liang;

Published by: Geophysical Research Letters      Published on:

YEAR: 2022     DOI: 10.1029/2022GL098627

Ionosphere; Giant Undulations; plasmapause; plasmapause surface waves

Multi-scale ionosphere responses to the May 2017 magnetic storm over the Asian sector

We investigate multi-scale ionospheric responses to the May 27, 2017, geomagnetic storm over the Asian sector by using multi-instrumental observations, including ground-based global navigation satellite systems (GNSS) network, constellation observing system for meteorology, ionosphere and climate radio occultation, the FengYun-3C (FY-3C) GNSS occultation sounder electron density profiles and in situ plasma density observations provided by both Swarm and defense meteorological satellite program missions. This geomagnetic storm was an intense storm with the minimum symmetric horizontal component reaching - 150\ nT and was caused by a coronal mass ejection released on May 23. The main observations are summarized below: (1) two ionospheric positive storm periods were observed. The first one was observed in the noon\textendashafternoon sector during the main phase of the storm on May 28, with nearly 120\% TEC enhancement. The second one was of a smaller scale and occurred on the nightside during the recovery phase of the storm on May 29. The first dayside positive storm was initiated by the interplanetary magnetic field (IMF) Bz southward turning and eastward penetration electric field, while the second nightside one was terminated by a later southward turning of the IMF Bz since the Asian sector was on the nightside and the penetration electric field changed westward. (2) A negative storm occurred from 00:00 to 12:00 UT on May 30 over the Asian sector, nearly 2\ days after the main phase, which was due to the thermospheric composition change, i.e., decrease in the O/N₂ ratio, as shown in the TIMED/GUVI measurements. (3) A band-like TEC enhancement was observed aligning in the northwest\textendashsoutheast direction and propagated slowly southwestward from 15:00 to 20:00 UT (23:00\textendash04:00 LT, near midnight) on May 28 during the recovery phase of the storm. In situ density observations from the Swarm B and DMSP F15\&16 satellites confirmed the density enhancement at 510\ km and 850\ km, respectively, and revealed that this band-like TEC enhancement structure resembles the so-called plasma blob. The similarities of the observed plasma blob characteristics in terms of spatial structure, propagation trend and temporal evolution with the nighttime traveling ionospheric disturbance (TID) are consistent with the TID-blob theory.

Liu, Lei; Zou, Shasha; Yao, Yibin; Aa, Ercha;

Published by: GPS Solutions      Published on: 12/2019

YEAR: 2020     DOI: 10.1007/s10291-019-0940-1

Blob structure; Positive and negative ionosphere responses; TID; Geomagnetic storms

Latitudinal features of Total Electron Content over the African and European longitude sector following the St. Patrick’s day storm of 2015

Paul, A; Kascheyev, A; Rodriguez-Bouza, M; PATHAK, K; Ferreira, AA; Shetti, D; Yao, JN;

Published by: Advances in Space Research      Published on:

YEAR: 2018     DOI:

Analysis of the global ionospheric disturbances of the March 2015 great storm

The global ionospheric storm in March 2015 was investigated by using data from over 3000 GPS stations worldwide. In this study, total electron content (TEC), rate of TEC (ROT), and ROT\textquoterights standard deviation rate of the TEC index, as well as the second-order difference operator TECT, were considered as main characteristic methods to distinguish ionosphereic disturbances. The results show that (1) based on the multiple methods above, we all observed that for the first time, there were three equatorward traveling ionospheric disturbances (TIDs) in the main phase of this storm. In North America, the disturbance zone expanded to ~40\textdegreeN; the disturbance periods and AE peak stages were roughly synchronous. We suggest that these three TIDs were induced by the propagation of atmospheric gravity waves to low latitudes under the action of AE. (2) The most intense positive storm occurred over South America and the South Atlantic (over 300\% enhancement; 00:00\textendash05:00 UT on 18 March), whereas a negative storm was observed in the corresponding region of the Northern Hemisphere. Such inverse hemispheric asymmetry in intensity and structure can be explained by the variations of the thermospheric composition, the IMF B_y component, and the geomagnetic intensity. (3) On 18 March, a negative storm dominated globally (except at certain low latitudes), and tended to propagate equatorward and decay with time, which could be largely attributed to the storm circulation theory. And the evolution of the negative storm was further characterized by the f_oF₂ variations of ionosondes.

Yao, Yibin; Liu, Lei; Kong, Jian; Zhai, Changzhi;

Published by: Journal of Geophysical Research: Space Physics      Published on: 11/2016

YEAR: 2016     DOI: 10.1002/2016JA023352

Transpolar arc observation after solar wind entry into the high-latitude magnetosphere

Recently, Cluster observations have revealed the presence of new regions of solar wind plasma entry at the high-latitude magnetospheric lobes tailward of the cusp region, mostly during periods of northward interplanetary magnetic field. In this study, observations from the Global Ultraviolet Imager (GUVI) experiment on board the TIMED spacecraft and Wideband Imaging Camera imager on board the IMAGE satellite are used to investigate a possible link between solar wind entry and the formation of transpolar arcs in the polar cap. We focus on a case when transpolar arc formation was observed twice right after the two solar wind entry events were detected by the Cluster spacecraft. In addition, GUVI and IMAGE observations show a simultaneous occurrence of auroral activity at low and high latitudes after the second entry event, possibly indicating a two-part structure of the continuous band of the transpolar arc.

Mailyan, B.; Shi, Q.; Kullen, A.; Maggiolo, R.; Zhang, Y.; Fear, R.; Zong, Q.-G.; Fu, S; Gou, X.; Cao, X.; Yao, Z.; Sun, W.; Wei, Y.; Pu, Z;

Published by: Journal of Geophysical Research: Space Physics      Published on: 05/2015

YEAR: 2015     DOI: 10.1002/2014JA020912

magnetosphere-ionosphere coupling; transpolar arcs; in situ measurements

The relationship between solar wind entry processes and transpolar arc formation

Mailyan, Bagrat; Shi, Quanqi; Maggiolo, Romain; Zong, Qiugang; Cao, Xin; Zhang, Yongliang; Yao, Zhonghua; Fu, SuiYan; Wei, Yong; Pu, Zuyin;

Published by:       Published on:

YEAR: 2014     DOI:

On transpolar arc formation correlated with solar wind entry at high latitude magnetosphere

Mailyan, Bagrat; Shi, Quanqi; Maggiolo, Romain; Zong, Qiugang; Fu, SuiYan; Zhang, Yongliang; Yao, Zhonghua; Sun, W;

Published by:       Published on:

YEAR: 2014     DOI: