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Found 2061 entries in the Bibliography.
Showing entries from 201 through 250
| 2021 |
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Quantifying the Impact of Dynamic Storm-Time Exospheric Density on Plasmaspheric Refilling Waldrop, Lara; Cucho-Padin, Gonzalo; Maruyama, Naomi; Published by: Earth and Space Science Open Archive ESSOAr Published on: |
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Transpolar arcs: Seasonal dependence identified by an automated detection algorithm Bower, Gemma; Milan, Stephen; Paxton, Larry; Published by: Earth and Space Science Open Archive ESSOAr Published on: |
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Ionospheric and thermospheric contributions in TIMED/GUVI O 135.6 nm radiances Zhang, Yongliang; Paxton, Larry; Schaefer, Robert; Published by: Journal of Geophysical Research: Space Physics Published on: |
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Schaefer, Robert; Paxton, Larry; Zhang, Yongliang; Kil, Hyosub; Romeo, Giuseppe; Wolven, Brian; Yonker, Justin; Published by: Published on: |
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Themens, David; Jayachandran, Thayyil; McCaffrey, Anthony; Reid, Benjamin; Watson, Chris; Published by: 43rd COSPAR Scientific Assembly. Held 28 January-4 February Published on: |
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Dual-lobe reconnection and cusp-aligned auroral arcs Milan, Stephen; Bower, Gemma; Carter, Jennifer; Paxton, Larry; Anderson, Brian; Hairston, Marc; Published by: Published on: |
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Watson, C; Themens, DR; Jayachandran, PT; Published by: Space Weather Published on: |
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The Universal Time Variations of the Intensity of Afternoon Aurora in Equinoctial Seasons The afternoon auroral emissions are investigated in the equinoxes for geomagnetically quiet conditions (Kp = 1) using auroral images from ultraviolet imager (UVI) aboard the Polar satellite. They are compared with solar illumination effects (the solar zenith angle [SZA] and the consequent ionospheric conductivity) and the dipole tilt angle, as well as the observational region 1 upward field-aligned currents (FACs) from AMPERE data. The averaged afternoon auroral emissions have pronounced universal time (UT) variations with v ... Wang, Lingmin; Luan, Xiaoli; Lei, Jiuhou; Lynch, Kristina; Zhang, Binzheng; Published by: Journal of Geophysical Research: Space Physics Published on: YEAR: 2021 DOI: 10.1029/2020JA028504 afternoon auroral emissions; auroral hot spots; dipole tilt angle; region 1 upward FACs; solar zenith angle; UT variations |
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The delayed ionospheric response is analyzed for two well-defined 27-day solar rotation periods in the year 2019 with solar radio flux index F10.7 and Global-scale Observations of the Limb and Disk (GOLD) data, like solar extreme ultraviolet (EUV) flux proxy, O/N2 column density ratio and peak electron density, as well as International Global Navigation Satellite System Service rapid high-rate total electron content (TEC) map data. Although the correlation between GOLD solar EUV flux proxy and TEC is similar to the correlati ... Schmölter, Erik; Berdermann, Jens; Codrescu, Mihail; Published by: Journal of Geophysical Research: Space Physics Published on: YEAR: 2021 DOI: 10.1029/2020JA028861 Ionosphere; solar proxies; time delay; total electron content |
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MLT Science Enabled by Atmospheric Lidars With the pioneering development and deployment of different types of narrowband sodium fluorescence lidars in Europe (1985) and North America (1990) along with subsequent potassium and iron lidars, temperature and wind profilers have been observed to investigate atmospheric dynamics in the mesosphere and lower thermosphere (MLT) in midlatitude, polar and equatorial regions. Their achieved resolution allows investigation ranging from small-scale gravity waves to long-term global change. This chapter highlights MLT science ena ... She, Chiao-Yao; Liu, Alan; Yuan, Tao; Yue, Jia; Li, Tao; Ban, Chao; Friedman, Jonathan; Published by: Published on: YEAR: 2021 DOI: 10.1002/9781119815631.ch20 Geomagnetic storms; atmospheric stabilities; atmospheric state; climatology; clustered instrumentation; gravity wave dynamics; MLT science; resonance fluorescence lidars; sporadic metal layers; thermospheric metal layers |
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Impact of Storm-Enhanced Density (SED) on Ion Upflow Fluxes During Geomagnetic Storm The impact of the dynamic evolution of the Storm-Enhanced Density (SED) on the upward ion fluxes during the March 06, 2016 geomagnetic storm is studied using comprehensive multi-scale datasets. This storm was powered by a Corotating Interaction Region (CIR), and the minimum Sym-H reached ∼−110 nT. During the ionospheric positive storm phase, the SED formed and the associated plume and polar cap patches occasionally drifted anti-sunward across the polar cap. When these high-density structures encountered positive vertica ... Zou, Shasha; Ren, Jiaen; Wang, Zihan; Sun, Hu; Chen, Yang; Published by: Frontiers in Astronomy and Space Sciences Published on: |
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Evaluating Auroral Forecasts Against Satellite Observations The aurora is a readily visible phenomenon of interest to many members of the public. However, the aurora and associated phenomena can also significantly impact communications, ground-based infrastructure, and high-altitude radiation exposure. Forecasting the location of the auroral oval is therefore a key component of space weather forecast operations. A version of the OVATION-Prime 2013 auroral precipitation model (Newell et al., 2014, https://doi.org/10.1002/2014sw001056) was used by the UK Met Office Space Weather Operat ... Mooney, M.; Marsh, M.; Forsyth, C.; Sharpe, M.; Hughes, T.; Bingham, S.; Jackson, D.; Rae, I.; Chisham, G.; Published by: Space Weather Published on: YEAR: 2021 DOI: 10.1029/2020SW002688 AURORA; auroral forecasting; forecast verification; OVATION-Prime 2013; ROC scores; space weather |
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Assimilative Mapping of Electron Flux Using SSUSI Lyman-Birge-Hopfield Emissions Far ultraviolet (FUV) imaging of the aurora from space provides great insight into the dynamic coupling of the Earth’s atmosphere, ionosphere and magnetosphere on global scales. To gain quantitative understanding of these coupling processes, the global distribution of auroral energy flux is required, but the inversion of FUV emission to derive precipitating auroral particles’ energy flux is not straightforward. Furthermore, the spatial coverage of FUV imaging from LEO altitudes is often insufficient to achieve global map ... Published by: Published on: Assimilative mapping; Electron flux; Far ultraviolet imaging; Lyman-Birge-Hopfield emission |
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Ionospheric day-to-day variability is essential for understanding the space environment, while it is still challenging to properly quantify and forecast. In the present work, the day-to-day variability of F2 layer peak electron densities (NmF2) is examined from both observational and modeling perspectives. Ionosonde data over Wuhan station (30.5°N, 114.5°E; 19.3°N magnetic latitude) are compared with simulations from the specific dynamics Whole Atmosphere Community Climate Model with thermosphere and ionosphere eXtension ... Zhou, Xu; Yue, Xinan; Liu, Han-Li; Lu, Xian; Wu, Haonan; Zhao, Xiukuan; He, Jianhui; Published by: Journal of Geophysical Research: Space Physics Published on: YEAR: 2021 DOI: 10.1029/2020JA028589 Ionosphere; day-to-day variability; ionosonde; NmF2; TIEGCM; WACCM-X |
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Observations of far-ultraviolet (FUV) dayglow by the Global-scale Observations of Limb and Disk (GOLD) mission provide a new opportunity to monitor relative composition changes in the upper atmosphere as well as solar extreme ultraviolet (EUV) variability. Relative composition changes are quantified by ΣO/N2, the column density ratio of atomic oxygen to molecular nitrogen, while QEUV provides a measure of the solar EUV energy flux from 1 to 45 nm into the upper atmosphere. This spectral range provides the ionizing radiation ... Correira, J.; Evans, J.; Lumpe, J.; Krywonos, A.; Daniell, R.; Veibell, V.; McClintock, W.; Eastes, R.; Published by: Journal of Geophysical Research: Space Physics Published on: YEAR: 2021 DOI: 10.1029/2021JA029517 GOLD; neutral composition; ON2; QEUV; radiative recombination; thermosphere |
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Observations showing the development of Subauroral Longitudinally Extended Emigerssions on a global scale are presented. It is demonstrated that they occur as a separation of an east-west arc-like band of luminosity that detaches away from the equatorward edge of the auroral distribution following episodes of auroral streamer production. They persist for time intervals on the order of ∼30 min and devolve into patchy disjointed segments before they fade. Emissions are seen in both 557.7 nm OI and 391.4 nm 1NG lines, and 630 ... Published by: Journal of Geophysical Research: Space Physics Published on: YEAR: 2021 DOI: 10.1029/2020JA028556 Giant Undulations; STEVE; streamers; Subauroral Bands; Subauroral Polarization Streams; substorms |
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The geomagnetic storm that occurred on 25 August 25 2018, that is, during the minimum of solar cycle 24, is currently the strongest ever probed by the first China Seismo-Electromagnetic Satellite (CSES-01). By integrating the in situ measurements provided by CSES-01 (orbiting at altitude of 507 km) and by Swarm A satellite (orbiting at ca., 460 km) with ground-based observations (ionosondes, magnetometers, and Global Navigation Satellite System receivers), we investigate the ionospheric response at lower- and mid-latitudes o ... Spogli, L.; Sabbagh, D.; Regi, M.; Cesaroni, C.; Perrone, L.; Alfonsi, L.; Di Mauro, D.; Lepidi, S.; Campuzano, S.; Marchetti, D.; De Santis, A.; Malagnini, A.; Scotto, C.; Cianchini, G.; Shen, Xu; Piscini, A.; Ippolito, A.; Published by: Journal of Geophysical Research: Space Physics Published on: YEAR: 2021 DOI: 10.1029/2020JA028368 Geomagnetic storms; Equatorial Electrojet; in situ plasma density; ionospheric elctroduamics; Ionospheric storms; low-latitude ionosphere |
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Traveling ionospheric disturbances (TIDs) and their neutral counterparts known as traveling atmospheric disturbances (TADs) are believed to play a role in communicating inputs to other locations in the fluid. While these two phenomena are believed to be connected, they may not have a one-to-one correspondence as the geomagnetic field influences the TID but has no direct impact on the TAD. The relative amplitudes of the perturbations seen in the ionosphere and atmosphere have been observed but rarely together. This study repo ... England, Scott; Greer, Katelynn; Zhang, Shun-Rong; Evans, Scott; Solomon, Stanley; Eastes, Richard; McClintock, William; Burns, Alan; Published by: Journal of Geophysical Research: Space Physics Published on: YEAR: 2021 DOI: 10.1029/2021JA029248 |
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We analyze horizontal plasma drifts measured by the Defense Meteorological Satellite Program satellites during two intense magnetic storms. It is found, for the first time, that westward plasma flows associated with subauroral polarization streams (SAPS) in the dusk-evening sector penetrate continuously to equatorial latitudes. The westward ion drifts between subauroral and equatorial latitudes occur nearly simultaneously. The latitudinal profile of the westward ion drifts at low latitudes (approximately within ±30° magnet ... Huang, Chao-Song; Zhang, Yongliang; Wang, Wenbin; Lin, Dong; Wu, Qian; Published by: Journal of Geophysical Research: Space Physics Published on: YEAR: 2021 DOI: 10.1029/2021JA030001 Electric field; Ionosphere; ionospheric plasma drift; penetration electric field; Subauroral Polarization Streams; thermospheric wind |
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Equatorial Ionization Anomaly Variations During Geomagnetic Storms The equatorial ionization anomaly (EIA) was discovered in the 1940s. Since then, the research on ionospheric storm effects at the equatorial and low latitudes has become one of the hottest topics in the ionospheric community. During the past 2 decades, large amounts of ionospheric and thermospheric data from the ground-based and satellite-borne observations and also from the novel capability of three-dimensional numerical models stimulated the ionospheric weather studies. Recent scientific progresses on the EIA response to g ... Published by: Published on: YEAR: 2021 DOI: 10.1002/9781119815617.ch13 Geomagnetic storms; Equatorial ionization anomaly; equatorial ionospheric response; equatorial regions; low latitude regions; physical mechanisms |
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We present new measurements of the vertical density profile of the Earth s atmosphere at altitudes between 70 and 200 km, based on Earth occultations of the Crab Nebula observed with the X-ray Imaging Spectrometer onboard Suzaku and the hard X-ray Imager onboard Hitomi. X-ray spectral variation due to the atmospheric absorption is used to derive tangential column densities of the absorbing species, that is, N and O including atoms and molecules, along the line of sight. The tangential column densities are then inverted to ob ... Katsuda, Satoru; Fujiwara, Hitoshi; Ishisaki, Yoshitaka; Yoshitomo, Maeda; Mori, Koji; Motizuki, Yuko; Sato, Kosuke; Tashiro, Makoto; Terada, Yukikatsu; Published by: Journal of Geophysical Research: Space Physics Published on: YEAR: 2021 DOI: 10.1029/2020JA028886 Crab Nebula; Hitomi; occultation; Suzaku; upper atmosphere; X-rays |
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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 ... 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 |
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This paper reports that plasma density depletions appearing at middle latitudes near sunrise survived until afternoon on 29 May 2017 during the recovery phase of a geomagnetic storm. By analyzing GPS data collected in Japan, we investigate temporal variations in the horizontal two-dimensional distribution of total electron content (TEC) during the geomagnetic storm. The SYM-H index reached −142 nT around 08 UT on 28 May 2017. TEC depletions extending up to approximately 38°N along the meridional direction appeared over Ja ... Otsuka, Yuichi; Shinbori, Atsuki; Sori, Takuya; Tsugawa, Takuya; Nishioka, Michi; Huba, Joseph; Published by: Earth and Planetary Physics Published on: YEAR: 2021 DOI: 10.26464/epp2021046 Ionosphere; GPS; ionospheric irregularity; plasma bubble; SAMI2 |
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Global Effects of a Polar Solar Eclipse on the Coupled Magnetosphere-Ionosphere System It is well-known that solar eclipses can significantly impact the ionosphere and thermosphere, but how an eclipse influences the magnetosphere-ionosphere system is still unknown. Using a coupled magnetosphere-ionosphere-thermosphere model, we examined the impact on geospace of the northern polar-region eclipse that occurred on June 10, 2021. The simulations reveal that the eclipse-induced reduction in polar ionospheric conductivity causes large changes in field-aligned current, cross-polar cap potential and auroral activity. ... Chen, Xuetao; Dang, Tong; Zhang, Binzheng; Lotko, William; Pham, Kevin; Wang, Wenbin; Lin, Dong; Sorathia, Kareem; Merkin, Viacheslav; Luan, Xiaoli; Dou, Xiankang; Luo, Bingxian; Lei, Jiuhou; Published by: Geophysical Research Letters Published on: YEAR: 2021 DOI: 10.1029/2021GL096471 auroral activity; magnetosphere-ionosphere coupling; polar solar eclipse |
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We describe a long-term data set of global average thermospheric mass density derived from orbit data on ∼7,700 objects in low Earth orbit, via the effect of atmospheric drag. The data cover the years 1967–2019 and altitudes 250–575 km, and the temporal resolution is 3–4 days for most years. The data set is an extension and revision of a previous version. The most important change is the use of more precise orbit data: special perturbation state vectors are now used starting in 2001, instead of mean Keplerian orbital ... Emmert, J.; Dhadly, M.; Segerman, A.; Published by: Journal of Geophysical Research: Space Physics Published on: YEAR: 2021 DOI: 10.1029/2021JA029455 |
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Auroral Energy Flux and Joule Heating Derived From Global Maps of Field-Aligned Currents We calculate auroral energy flux and Joule heating in the high-latitude ionosphere for 27 geomagnetically active days using two-dimensional maps of field-aligned currents determined by the Active Magnetosphere and Planetary Response Experiment. The energy input to the ionosphere due to Joule heating increases more rapidly with geomagnetic activity than that due to precipitating particles. The energy flux varies more smoothly with time than Joule heating, which is impulsive in nature on time scales from minutes to tens of min ... Published by: Geophysical Research Letters Published on: YEAR: 2021 DOI: 10.1029/2020GL091527 Geomagnetic storms; Auroral energy flux; auroral energy input; auroral substorms; Joule heating; ring current |
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Statistical Analysis of Throat Aurora Using Long Term DMSP/SSUSI Observation Throat aurora is believed to be associated with magnetopause indentations and has direct implications on magnetopause reconnection. In this study, for the first time, we use Defense Meteorological Satellite Program/Special Sensor Ultraviolet Spectrographic Imager observations over ∼14 years to characterize the throat aurora occurrence, latitudinal extent, seasonal, and its solar cycle dependence. We identified 386 throat aurora cases during the different passes of the satellite over the northern hemisphere. The latitudinal ... Selvakumaran, R.; Han, De-Sheng; Gokani, Sneha; Zhang, Y.; Published by: Journal of Geophysical Research: Space Physics Published on: YEAR: 2021 DOI: 10.1029/2021JA029164 |
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Neutral Hydrogen in the Terrestrial Thermosphere and Exosphere The exosphere is the interface between the Earth s neutral atmosphere and interplanetary space. Our understanding of this important interface, through observations of its mean state and its response to external forcing, will provide important constraints as we seek to develop a complete picture of our complicated space-atmosphere system. This chapter will highlight the contributions of ground-based geocoronal hydrogen observations to our understanding of this system. Observations are made throughout the night; the base of th ... Published by: Published on: YEAR: 2021 DOI: 10.1002/9781119815631.ch8 Fabry-Perot spectrometer; geocoronal Balmer; ground-based geocoronal hydrogen observations; hydrogen density profile; hydrostatic equilibrium; neutral hydrogen; terrestrial exosphere; terrestrial thermosphere |
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Ionosphere and Thermosphere Coupling at Mid- and Subauroral Latitudes This chapter addresses the ionosphere–thermosphere (I/T) coupling phenomena. We define I/T coupling as the dynamical interaction between plasma and neutral particles in the upper atmosphere. This interaction involves the ionosphere response to changes in the thermospheric wind, composition, and temperature, and how the thermosphere dynamics and thermal state are affected by plasma electrodynamics, which may well be under the influence of magnetosphere–ionosphere coupling. It has been the main research focus for decades a ... Published by: Published on: YEAR: 2021 DOI: 10.1002/9781119815617.ch15 ionosphere–thermosphere coupling; ionospheric dynamics; ionospheric responses; subauroral latitudes; thermospheric neutral winds; thermospheric variations |
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We advance the modeling capability of electron particle precipitation from the magnetosphere to the ionosphere through a new database and use of machine learning (ML) tools to gain utility from those data. We have compiled, curated, analyzed, and made available a new and more capable database of particle precipitation data that includes 51 satellite years of Defense Meteorological Satellite Program (DMSP) observations temporally aligned with solar wind and geomagnetic activity data. The new total electron energy flux particl ... McGranaghan, Ryan; Ziegler, Jack; Bloch, Téo; Hatch, Spencer; Camporeale, Enrico; Lynch, Kristina; Owens, Mathew; Gjerloev, Jesper; Zhang, Binzheng; Skone, Susan; Published by: Space Weather Published on: YEAR: 2021 DOI: 10.1029/2020SW002684 space weather; magnetosphere-ionosphere coupling; data science; evaluation; machine learning; particle precipitation |
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Implication of Tidal Forcing Effects on the Zonal Variation of Solstice Equatorial Plasma Bubbles Equatorial plasma bubbles (EPBs) are plasma depletions that can occur in the nighttime ionospheric F region, causing scintillation in satellite navigation and communications signals. Past research has shown that EPB occurrence rates are higher during the equinoxes in most longitude zones. An exception is over the central Pacific and African sectors, where EPB activity has been found to maximize during solstice. Tsunoda et al. (2015) hypothesized that the solstice maxima in these two sectors could be driven by a zonal wavenum ... Chang, Loren; Salinas, Cornelius; Chiu, Yi-Chung; , Jones; Rajesh, P.; Chao, Chi-Kuang; Liu, Jann-Yenq; Lin, Charles; Hsiao, Tung-Yuan; Published by: Journal of Geophysical Research: Space Physics Published on: YEAR: 2021 DOI: 10.1029/2020JA028295 Ionosphere; Atmospheric tides; equatorial plasma bubble; scintillation; vertical coupling; wind dynamo |
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Determination of Auroral Electrodynamic Parameters From AMPERE Field-Aligned Current Measurements We calculate high latitude electrodynamic parameters using global maps of field-aligned currents from the Active Magnetosphere and Planetary Response Experiment (AMPERE). The model is based on previous studies that relate field-aligned currents to auroral Pedersen and Hall conductances measured by incoherent scatter radar. The field-aligned currents and conductances are used to solve for the electric potential at high latitudes from which electric fields are computed. The electric fields are then used with the conductances t ... Robinson, R.; Zanetti, Larry; Anderson, Brian; Vines, Sarah; Gjerloev, Jesper; Published by: Space Weather Published on: YEAR: 2021 DOI: 10.1029/2020SW002677 space weather; auroral currents; auroral electrodynamics; conductivities; electric fields; field-aligned currents |
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Explicit IMF By-Dependence in Geomagnetic Activity: Quantifying Ionospheric Electrodynamics Geomagnetic activity is mainly driven by the southward (Bz) component of the interplanetary magnetic field (IMF), which dominates all solar wind coupling functions. Coupling functions also depend on the absolute value of the dawn-dusk (By) component of the IMF, but not on its sign. However, recent studies have shown that for a fixed level of solar wind driving, auroral electrojets in the Northern Hemisphere (NH) are stronger for By \textgreater 0 than for By \textless 0 during NH winter. In NH summer, the dependence on the B ... Holappa, L.; Robinson, R.; Pulkkinen, A.; Asikainen, T.; Mursula, K.; Published by: Journal of Geophysical Research: Space Physics Published on: YEAR: 2021 DOI: 10.1029/2021JA029202 space weather; magnetosphere-ionosphere coupling; field-aligned currents; geomagnetic activity |
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Geomagnetic Pulsations Driving Geomagnetically Induced Currents Geomagnetically induced currents (GICs) are driven by the geoelectric field induced by fluctuations of Earth s magnetic field. Drivers of intense GICs are often associated with large impulsive events such as coronal mass ejections. To a lesser extent fluctuations from regular oscillations of the geomagnetic field, or geomagnetic pulsations, have also been identified as possible drivers of GICs. In this work we show that these low-frequency pulsations are directly observed in measured GIC data from power networks. Due to the ... Heyns, M.; Lotz, S.; Gaunt, C.; Published by: Space Weather Published on: YEAR: 2021 DOI: 10.1029/2020SW002557 space weather; geomagnetic pulsations; geomagnetically induced currents |
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Equatorial Ionospheric Electrodynamics The low-latitude ionosphere is one of the most dynamic regions of the Earth s upper atmosphere. The morphology of this region is controlled by radiative and coupled chemical, neutral, and plasma transport processes. Equatorial electrodynamics plays a fundamental role on the low-latitude plasma density, total electron content (TEC), and plasma structures and waves extending from the E-region to the protonosphere. Ground-based and satellite measurements over the last six decades determined the climatology of quiet- and storm-t ... Published by: Published on: YEAR: 2021 DOI: 10.1002/9781119815617.ch9 total electron content; equatorial ionospheric electrodynamics; low-latitude plasma density; quiet-time equatorial plasma drifts; storm-time equatorial electric fields |
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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 el ... 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 |
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Recent attention has been given to mesoscale phenomena across geospace (∼10 s km to 500 km in the ionosphere or ∼0.5 RE to several RE in the magnetosphere), as their contributions to the system global response are important yet remain uncharacterized mostly due to limitations in data resolution and coverage as well as in computational power. As data and models improve, it becomes increasingly valuable to advance understanding of the role of mesoscale phenomena contributions—specifically, in magnetosphere-ionosphere c ... Gabrielse, Christine; Nishimura, Toshi; Chen, Margaret; Hecht, James; Kaeppler, Stephen; Gillies, Megan; Reimer, Ashton; Lyons, Larry; Deng, Yue; Donovan, Eric; Evans, Scott; Published by: Frontiers in Physics Published on: |
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Planetary Waves and Their Impact on the Mesosphere, Thermosphere, and Ionosphere Large-scale planetary waves (also known as Rossby waves), such as the Quasi-two day wave, 5 day wave and Kelvin wave, play crucial roles in coupling the lower and middle atmosphere to the mesosphere, thermosphere and ionosphere. Upward propagation and global structure of planetary waves in the stratosphere and mesosphere are affected by the zonal mean winds. Baroclinic or barotropic instability of the background mesospheric winds can amplify the waves en route to the upper atmosphere. Fast traveling planetary waves with deep ... Yue, Jia; Lieberman, Ruth; Chang, Loren; Published by: Published on: YEAR: 2021 DOI: 10.1002/9781119815631.ch10 barotropic instability; E-region dynamo electric fields; F-region dynamo electric fields; Kelvin waves; mesosphere; planetary waves; plasma drift; thermosphere-ionosphere system |
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The Earth s atmosphere is a complicated environment. Different physical processes affect it depending on the altitude and latitude, among other factors. Three different aspects of the Earth s upper atmosphere are investigated here, using two different techniques. These investigations are: the mid-latitude midnight temperature maximum (MTM), the mesosphere and low-thermosphere Kelvin-Helmholtz instability (KHI), and the advective acceleration in the E-region. All of these studies occur in the Earth s thermosphere and expand o ... Published by: Published on: Advective acceleration; E-region neutral wind forcing; Kelvin-Helmholtz instability; Midnight temperature maximum |
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We use the \textlessi\textgreateram\textlessi/\textgreater, \textlessi\textgreateran, as\textlessi/\textgreater and the \textlessi\textgreateraσ\textlessi/\textgreater geomagnetic indices to the explore a previously overlooked factor in magnetospheric electrodynamics, namely the inductive effect of diurnal motions of the Earth’s magnetic poles toward and away from the Sun caused by Earth’s rotation. Because the offset of the (eccentric dipole) geomagnetic pole from the rotational axis is roughly twice as large in the so ... Lockwood, Mike; Haines, Carl; Barnard, Luke; Owens, Mathew; Scott, Chris; Chambodut, Aude; McWilliams, Kathryn; Published by: Journal of Space Weather and Space Climate Published on: YEAR: 2021 DOI: 10.1051/swsc/2020077 |
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TIMED/Global Ultraviolet Imager (GUVI) limb measurements of far-ultraviolet airglow emission have been used to investigate middle-low latitude thermospheric composition and neutral temperature responses to the 20 and 21 November 2003 (day of year [DOY] 324 and 325) superstorm. Altitude profiles of O, N2 number densities and temperature, as well as O/N2 column density ratio (∑O/N2), on the storm days along the GUVI limb tracks are compared with those on DOY 323 (quiet time). The storm-time composition and temperature respon ... Yu, Tingting; Wang, Wenbin; Ren, Zhipeng; Yue, Jia; Yue, Xinan; He, Maosheng; Published by: Journal of Geophysical Research: Space Physics Published on: YEAR: 2021 DOI: 10.1029/2020JA028427 neutral composition; altitude profile; hemispheric asymmetry in composition responses; neutral temperature; superstorm; transition heights of O responses |
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The Response of Middle Thermosphere (∼160 km) Composition to the November 20 and 21, 2003 Superstorm TIMED/GUVI limb measurements and first-principles simulations from the Thermosphere Ionosphere Electrodynamics Global Circulation Model (TIEGCM) are used to investigate thermospheric atomic oxygen (O) and molecular nitrogen (N2) responses in the middle thermosphere on a constant pressure surface (∼160 km) to the November 20 and 21, 2003 superstorm. The consistency between GUVI observations and TIEGCM simulated composition changes allows us to utilize TIEGCM outputs to investigate the storm-time behaviors of O and N2 system ... Yu, Tingting; Wang, Wenbin; Ren, Zhipeng; Cai, Xuguang; Yue, Xinan; He, Maosheng; Published by: Journal of Geophysical Research: Space Physics Published on: YEAR: 2021 DOI: 10.1029/2021JA029449 atomic oxygen; GUVI limb observations; middle thermosphere; molecular nitrogen; storm-time perturbations; TIEGCM |
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Corotation of ring current auroral spots at sub-auroral latitudes We report observations of auroral spots s at sub-auroral latitudes. The auroral spots occurred during storm-recovery phases and corotated with the Earth at a speed either higher (super-rotation) or lower (sub-rotation) than the Earth\textquoterights rotation rate. In the dawn side, the spots have a slightly higher probability of super-rotation than that of the duskside auroral spots. The super- and sub-rotation is likely due to dynamics of the plasmasphere that is controlled by both drag (sub-rotation) and solar wind driv ... Zhang, Yongliang; Paxton, Larry; Published by: Journal of Atmospheric and Solar-Terrestrial Physics Published on: Jan-02-2020 YEAR: 2020 DOI: 10.1016/j.jastp.2020.105195 |
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A new model of exospheric temperatures has been developed, with the objective of predicting global values with greater spatial and temporal accuracy. From these temperatures, the neutral densities in the thermosphere can be calculated, through use of the Naval Research Laboratory Mass Spectrometer and Incoherent Scatter radar Extended (NRLMSISE-00) model. The exospheric temperature model is derived from measurements of the neutral densities on several satellites. These data were sorted into triangular c ... Weimer, D.; Mehta, P.; Tobiska, W.; Doornbos, E.; Mlynczak, M.; Drob, D.; Emmert, J.; Published by: Space Weather Published on: 12/2019 YEAR: 2020 DOI: 10.1029/2019SW002355 |
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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 s ... 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 |
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Equatorial plasma bubbles (EPBs) are common features of the equatorial and low-latitude ionosphere and are known to cause radio wave scintillation which leads to the degradation of communication and navigation systems. Although these structures have been studied for decades, a full understanding of their evolution and dynamics remains important for space weather mitigation purposes. In this study, we present cases of EPBs occurrences around April and July 2012 geomagnetic storm periods over the African ... Giday, Nigussie; Katamzi-Joseph, Zama; Stoneback, Russell; Published by: Advances in Space Research Published on: 04/2020 YEAR: 2020 DOI: 10.1016/j.asr.2020.01.013 |
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A method to derive global O/N2 ratios from SSUSI/DMSP based on Re-AURIC algorithm Global thermospheric O/N2 column density ratios are obtained using the SSUSI/DMSP far-ultraviolet (FUV) dayglow data and the Re-AURIC simulation results. The Re-AURIC is derived from the AURIC algorithm after some old modules are updated. The calculation processes of O/N2 ratio are then established using the simulations of Re-AURIC to calibrate the ratios of the OI 135.6\ nm emission and N2 LBHS emission from SSUSI observations. The standard deviation (1σ) and correlation co ... Ding, GuangXing; Chen, Bo; Zhang, Xiaoxin; He, Fei; Published by: Journal of Atmospheric and Solar-Terrestrial Physics Published on: 03/2020 YEAR: 2020 DOI: 10.1016/j.jastp.2020.105196 |
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The present paper reports coordinated ionospheric irregularity measurements at optical as well as GPS wavelengths. Optical measurements were obtained from Tiny Ionospheric Photometer (TIP) sensors installed onboard the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) satellites. GPS radio signals were obtained from a dual frequency GPS receiver operational at Calcutta (22.58\textdegreeN, 88.38\textdegreeE geographic; geomagnetic dip: 32.96\textdegree; 13.00\textdegreeN, 161.63\textdegreeE g ... Paul, Ashik; Sur, Dibyendu; Haralambous, Haris; Published by: Advances in Space Research Published on: 03/2020 YEAR: 2020 DOI: 10.1016/j.asr.2019.11.035 GPS radio measurements; ionospheric irregularities; Northern crest of EIA; Optical measurements; solar minimum; TIP |
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Response of the low- to mid-latitude ionosphere to the geomagnetic storm of September 2017 We study the impact of the geomagnetic storm of 7\textendash9\ September\ 2017 on the low- to mid-latitude ionosphere. The prominent feature of this solar event is the sequential occurrence of two SYM-H minima with values of -146 and -115 nT on 8\ September at 01:08 and 13:56 UT, respectively. The study is based on the analysis of data from the Global Positioning System (GPS) stations and magnetic observatories located at different longitudinal sectors corresponding to the Pacific, Asia, Africa and the Amer ... Imtiaz, Nadia; Younas, Waqar; Khan, Majid; Published by: Annales Geophysicae Published on: 03/2020 YEAR: 2020 DOI: 10.5194/angeo-38-359-2020 |
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The onset of substorms is associated with bursty enhancements of Alfv\ en wave power throughout the magnetotail. While impossible to assess the total Alfv\ en wave power in the entire magnetotail, we have instead monitored waves that are funneled into the auroral acceleration region, in order to assess the temporal evolution of Alfv\ en wave power above the nightside auroral zone in relation to substorm phases. The substorms were grouped by three conditions: nonstorm periods, storm periods, and all (unc ... Keiling, Andreas; Thaller, Scott; Dombeck, John; Wygant, John; Published by: Journal of Geophysical Research: Space Physics Published on: 03/2020 YEAR: 2020 DOI: 10.1029/2019JA027444 Alfven wave; Alfvenic electron; AURORA; auroral acceleration; magnetotail; Substorm |
