GUVI

Global UltraViolet Imager

GUVI Biblio





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Found 2276 entries in the Bibliography.


Showing entries from 51 through 100


2022

The 15 January 2022 Hunga Tonga Eruption History as Inferred From Ionospheric Observations

On 15 January 2022, the Hunga Tonga-Hunga Ha’apai submarine volcano erupted violently and triggered a giant atmospheric shock wave and tsunami. The exact mechanism of this extraordinary eruptive event, its size and magnitude are not well understood yet. In this work, we analyze data from the nearest ground-based receivers of Global Navigation Satellite System to explore the ionospheric total electron content (TEC) response to this event. We show that the ionospheric response consists of a giant TEC increase followed by a s ...

Astafyeva, E.; Maletckii, B.; Mikesell, T.; Munaibari, E.; Ravanelli, M.; Coisson, P.; Manta, F.; Rolland, L.;

Published by: Geophysical Research Letters      Published on:

YEAR: 2022     DOI: 10.1029/2022GL098827

co-volcanic ionospheric disturbances; eruption timeline; GNSS; Hunga Tonga eruption; Ionosphere; ionospheric geodesy

A Simulation Study on the Variation of Thermospheric O/N2 With Solar Activity

The ratio of number density of atomic oxygen (O) to that of molecular nitrogen (N2) in the thermosphere (O/N2) on the constant pressure surface, which has complex temporal and spatial characteristics, is widely regarded as an important parameter connecting the terrestrial thermosphere and daytime ionosphere. Previous studies demonstrated that the thermospheric O/N2 increases with increasing solar activity, and the changes in O/N2 with solar activity show significant difference between winter and summer hemispheres. However, ...

Li, Zhongli; Luan, Xiaoli; Lei, Jiuhou; Ren, Dexin;

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

YEAR: 2022     DOI: 10.1029/2022JA030305

circulation; O/N2; photochemistry; solar cycle; thermosphere

Coherence Scale and Directivity of Nighttime Equatorial Plasma Irregularities: Results From Swarm Formation Flight

Since the launch in 2013, the three satellites of the Swarm constellation have been conducting multipoint observations of ionospheric plasma density. The variety of their flight formations is advantageous for investigating (a) coherence scale and (b) directivity of nighttime Equatorial Plasma Irregularities (EPIs). In this study, we address the two topics statistically using in situ plasma density measured at 2 Hz rates by the Swarm constellation from 2013 to 2021. Maximum cross-correlation coefficients between two Swarm den ...

Park, Jaeheung;

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

YEAR: 2022     DOI: 10.1029/2021JA030233

backward-C structure; Equatorial plasma irregularity; ionospheric coherence scale; swarm

Disappearance of the Polar Cap Ionosphere During Geomagnetic Storm on 11 May 2019

Multi-instrument data from Jang Bogo Station (JBS) in Antarctica were utilized to study ionospheric responses to the 11 May 2019 moderate geomagnetic storm. These include Vertical Incident Pulsed Ionospheric Radar (VIPIR)/Dynasonde, Fabry-Perot Interferometer (FPI), GPS vertical total electron content (vTEC), and magnetometer. The VIPIR/Dynasonde observed long-lasting (\textgreater11 hr) severe depletion of the electron density in the F-region ionosphere over JBS. During the depletion interval, GPS TEC also correspondingly d ...

Kwon, H.-J.; Kim, K.-H.; Jee, G.; Seon, J.; Lee, C.; Ham, Y.-B.; Hong, J.; Kim, E.; Bullett, T.; Auster, H.-U.; Magnes, W.; Kraft, S.;

Published by: Space Weather      Published on:

YEAR: 2022     DOI: 10.1029/2022SW003054

Impacts of Lower Thermospheric Atomic Oxygen and Dynamics on the Thermospheric Semiannual Oscillation Using GITM and WACCM-X

The latitudinal and temporal variation of atomic oxygen (O) is opposite between the empirical model, NRLMSISE-00 (MSIS) and the whole atmosphere model, whole atmosphere community climate model with thermosphere and ionosphere extension (WACCM-X) at 97–100 km. Atomic Oxygen from WACCM-X has maxima at solstices and summer mid-high latitudes, similar to [O] from Sounding of the Atmosphere using Broadband Emission Radiometry (SABER). We use the densities and dynamics from WACCM-X to drive the Global Ionosphere Thermosphere Mod ...

Malhotra, Garima; Ridley, Aaron; , Jones;

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

YEAR: 2022     DOI: 10.1029/2021JA029320

global ionosphere thermosphere modeling; semiannual oscillation; thermospheric and ionospheric SAO; thermospheric spoon mechanism; vertical coupling of thermosphere with lower atmosphere; whole atmosphere community climate model with thermosphere and ionosphere extension (WACCM-X)

Properties of AKR-Like Emissions Recorded by the Low Altitude Satellite DEMETER During 6.5 Years

Normally, auroral kilometric radiation (AKR) which is emitted in the auroral zones escapes from the Earth. But since a few decades very similar radiations are observed by ground-based receivers and by satellites at altitudes below the AKR generation area. They are called leaked AKR or AKR-like emissions because it is expected that there are linked to AKR. This paper deals with observations of such AKR-like emissions observed in the auroral zones (in the North and in the South) by the low-altitude satellite DEMETER. In total, ...

Parrot, M.; Němec, F.; Santolík, O.;

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

YEAR: 2022     DOI: 10.1029/2022JA030495

AKR; Ionosphere; magnetic activity

Climatology of Mesosphere and Lower Thermosphere Residual Circulations and Mesopause Height Derived From SABER Observations

In the mesosphere and lower thermosphere (MLT) region, residual circulations driven by gravity wave breaking and dissipation significantly impact constituent distribution and the height and temperature of the mesopause. The distribution of CO2 can be used as a proxy for the residual circulations. Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) CO2 volume mixing ratio (VMR) and temperature measurements from 2003 to 2020 are used to study the monthly climatology of MLT residual circulations and the mesop ...

Wang, Ningchao; Qian, Liying; Yue, Jia; Wang, Wenbin; Mlynczak, Martin; Russell, James;

Published by: Journal of Geophysical Research: Atmospheres      Published on:

YEAR: 2022     DOI: 10.1029/2021JD035666

climatology; interannual variation; MLT region; residual circulation; seasonal variation

Response of the Ionospheric TEC to SSW and Associated Geomagnetic Storm Over the American Low Latitudinal Sector

During the sudden stratospheric warming (SSW) event in 2013, we investigated the American low latitude around 75°W. We used 12 Global Positioning System (GPS) receivers, a pair of magnetometers, and the NASA Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) satellite airglow instrument to unveil the total electron content (TEC), inferred vertical drift, and the changes in the neutral composition, respectively. A major SSW characterized the 2013 SSW event with the main phase (7–27 January 2013) overlapped ...

Fashae, J.; Bolaji, O.; Rabiu, A.;

Published by: Space Weather      Published on:

YEAR: 2022     DOI: 10.1029/2021SW002999

equatorial ionization anomaly (EIA); geomagnetic storm; low-latitude ionosphere; sudden stratospheric wind (SSW)

Satellite In Situ Electron Density Observations of the Midlatitude Storm Enhanced Density on the Noon Meridional Plane in the F Region During the 20 November 2003 Magnetic Storm

Ionospheric storm enhanced density (SED) has been extensively investigated using total electron content deduced from GPS ground and satellite-borne receivers. However, dayside in situ electron density measurements have not been analyzed in detail for SEDs yet. We report in situ electron density measurements of a SED event in the Northern Hemisphere (NH) at the noon meridian plane measured by the Challenging Minisatellite Payload (CHAMP) polar-orbiting satellite at about 390 km altitude during the 20 November 2003 magnetic st ...

Lin, Chin; Sutton, Eric; Wang, Wenbin; Cai, Xuguang; Liu, Guiping; Henney, Carl; Cooke, David;

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

YEAR: 2022     DOI: 10.1029/2021JA029831

in situ plasma density; ionospheric electron density; prompt penetration electric field; Storm enhanced density; tongue of ionization

Assimilative Mapping of Auroral Electron Energy Flux Using SSUSI Lyman-Birge-Hopfield (LBH) Emissions

Far ultraviolet (FUV) imaging of the aurora from space provides great insight into the dynamic coupling of the atmosphere, ionosphere, and magnetosphere on global scales. To gain a 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 Low Earth Orbit (LEO) altitudes is often insufficient to achieve g ...

Li, J.; Matsuo, T.; Kilcommons, L.;

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

YEAR: 2022     DOI: 10.1029/2021JA029739

Spatial-Temporal Behaviors of Large-Scale Ionospheric Perturbations During Severe Geomagnetic Storms on September 7–8 2017 Using the GNSS, SWARM and TIE-GCM Techniques

Geomagnetic storms on 7–8 September 2017 triggered severe ionospheric disturbances that had a serious effect on satellite navigation and radio communication. Multiple observations derived from Global Navigation Satellite System receivers, Earth s Magnetic Field and Environment Explorers (SWARM) and the Thermosphere-Ionosphere -Electrodynamics General Circulation Model s simulations are utilized to investigate the spatial-temporal ionospheric behaviors under storm conditions. The results indicate that the electron density i ...

Li, Wang; Zhao, Dongsheng; He, Changyong; Hancock, Craig; Shen, Yi; Zhang, Kefei;

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

YEAR: 2022     DOI: 10.1029/2021JA029830

hemispheric asymmetry; ionospheric disturbances; Magnetic storms; thermospheric composition changes; TIE-GCM

Exospheric Temperature Measured by NASA-GOLD Under Low Solar Activity: Comparison With Other Data Sets

Exospheric temperature is one of the key parameters in constructing thermospheric models and has been extensively studied with in situ observations and remote sensing. The Global-scale Observations of the Limb and Disk (GOLD) at a geosynchronous vantage point provides dayglow limb images for two longitude sectors, from which we can estimate the terrestrial exospheric temperature since 2018. In this paper, we investigate climatological behavior of the exospheric temperature measured by GOLD. The temperature has positive corre ...

Park, Jaeheung; Evans, Joseph; Eastes, Richard; Lumpe, Jerry; van den Ijssel, Jose; Englert, Christoph; Stevens, Michael;

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

YEAR: 2022     DOI: 10.1029/2021JA030041

Aura/MLS; exospheric temperature; GOLD; ICON; swarm; TIMED/SABER

Transpolar Arcs: Seasonal Dependence Identified by an Automated Detection Algorithm

Transpolar arcs (TPAs) are auroral features that occur polewards of the main auroral oval suggesting that the magnetosphere has acquired a complicated magnetic topology. They are primarily a northward interplanetary magnetic field (IMF) auroral phenomenon, and their formation and evolution have no single explanation that is unanimously agreed upon. An automated detection algorithm has been developed to detect the occurrence of TPAs in UV images captured from the Special Sensor Ultraviolet Spectrographic Imager (SSUSI) instru ...

Bower, G.; Milan, S.; Paxton, L.; Imber, S.;

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

YEAR: 2022     DOI: 10.1029/2021JA029743

auroras; magnetosphere; transpolar arc

Creating a Database to Identify High-Latitude Scintillation Signatures With Unsupervised Machine Learning

In high latitudes, Global Navigation Satellite System (GNSS) signals experience scintillation due to moving irregularity structures in the ionosphere. These develop as a result of different physical mechanisms, which are as yet principally described on an elementary level for certain storm cases and events. Since there are years of GNSS data available from stations around the globe, we are investigating an unsupervised Machine Learning approach to extract a large variety of groups of scintillation events with similar feature ...

Bals, Anna-Marie; Thakrar, Chintan; Deshpande, Kshitija;

Published by: IEEE Journal of Radio Frequency Identification      Published on:

YEAR: 2022     DOI: 10.1109/JRFID.2022.3163913

Databases; Feature extraction; Fluctuations; global navigation satellite system; GNSS data noise elimination; GNSS scintillation; Indexes; Instruments; ionospheric scintillation event detection; Radiofrequency identification; unsupervised machine learning

Sounding Rocket Observation of Nitric Oxide in the Polar Night

An altitude profile of Nitric Oxide (NO) in the 80–110 km altitude range was measured in the polar night from a sounding rocket on 27 January 2020. The observations were made using the technique of stellar occultation with a UV spectrograph observing the γ (1,0) band of NO near 215 nm. The tangent point for the altitude profile was at 74° latitude, a location that had been in darkness for 80 days. The retrieved slant column density profile is interpreted using an assumed four-parameter analytic profile shape. Retrievals ...

Bailey, Scott; McClintock, William; Carstens, Justin; Thurairajah, Brentha; Das, Saswati; Randall, Cora; Harvey, Lynn; Siskind, David; Stevens, Michael; Venkataramani, Karthik;

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

YEAR: 2022     DOI: 10.1029/2021JA030257

Lower thermosphere; mesosphere; nitric oxide; polar night; sounding rocket; stellar occultation

Thermospheric density enhancement and limb O 130.4 nm radiance increase during geomagnetic storms

Zhang, Yongliang; Paxton, Larry; Schaefer, R;

Published by: Journal of Atmospheric and Solar-Terrestrial Physics      Published on:

YEAR: 2022     DOI:

Comments on “A new method to subtract dayglow for auroral observation of SSUSI in LBH ranges based on the improved AURIC” by Wang et al.(2021)

Zhang, Yongliang; Paxton, Larry; Schaefer, Robert;

Published by: Journal of Atmospheric and Solar-Terrestrial Physics      Published on:

YEAR: 2022     DOI:

Occurrence statistics of horse collar aurora

Bower, Gemma; Milan, Stephen; Paxton, Larry; Anderson, Brian;

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

YEAR: 2022     DOI:

Empirical modelling of SSUSI derived auroral ionization rates

Bender, Stefan; Espy, Patrick; Paxton, Larry;

Published by:       Published on:

YEAR: 2022     DOI:

The origin of midlatitude plasma depletions detected during the 12 February 2000 and 29 October 2003 geomagnetic storms

Kil, Hyosub; Chang, Hyeyeon; Lee, Woo; Paxton, Larry; Sun, Andrew; Lee, Jiyun;

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

YEAR: 2022     DOI:

Two different properties of ionospheric perturbations detected in the vicinity of the Korean Peninsula after the Hunga-Tonga volcanic eruption on 15 January 2022

Hong, Junseok; Kil, Hyosub; Lee, Woo; Kwak, Young-Sil; Choi, Byung-Kyu; Paxton, Larry;

Published by:       Published on:

YEAR: 2022     DOI:

The Terrestrial Magnetospheric Response to the 28th October 2021 CME

Waters, James; Jackman, Caitriona; Whiter, Daniel; Fogg, Alexandra; Lamy, Laurent; Carter, Jennifer; Fryer, Laura; Louis, Corentin; Carley, Eion; Briand, Carine; , others;

Published by:       Published on:

YEAR: 2022     DOI:

Novel Observations of the Aurora (NOA) from New Platforms

Paxton, LJ; Hibbitts, CA; Swartz, WH;

Published by:       Published on:

YEAR: 2022     DOI:

Increased Sensitivity FUV Spectrographic Imager

Schaefer, RK; Paxton, LJ; Zhang, Y; Kil, H; Liou, K;

Published by:       Published on:

YEAR: 2022     DOI:

Statistics of transpolar arcs identified by an automated detection algorithm

Bower, Gemma; Milan, Steve; Paxton, Larry; Imber, Suzie;

Published by:       Published on:

YEAR: 2022     DOI:

Height-integrated polar cap conductances during an average substorm

Carter, Jennifer; Milan, Steven; Lester, Mark; Forsyth, Colin; Paxton, Larry; Gjerloev, Jesper; Anderson, Brian;

Published by:       Published on:

YEAR: 2022     DOI:

Lobe Reconnection and Cusp-Aligned Auroral Arcs

Abstract Following the St. Patrick s Day (17 March) geomagnetic storm of 2013, the interplanetary magnetic field had near-zero clock angle for almost two days. Throughout this period multiple cusp-aligned auroral arcs formed in the polar regions; we present observations of, and provide a new explanation for, this poorly understood phenomenon. The arcs were observed by auroral imagers onboard satellites of the Defense Meteorological Satellite Program. Ionospheric flow measurements and observations of energetic particles from ...

Milan, S.; Bower, G.; Carter, J.; Paxton, L.; Anderson, B.; Hairston, M.;

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

YEAR: 2022     DOI: https://doi.org/10.1029/2021JA030089

Hemispheric Asymmetry in the Auroral Ionosphere-Thermosphere System

Liou, K; Zhang, Y-L; Paxton, LJ; Kil, H; Schaefer, R;

Published by:       Published on:

YEAR: 2022     DOI:

Temporal Evolution of Low-Latitude Plasma Blobs Identified From Multiple Measurements: ICON, GOLD, and Madrigal TEC

Low-latitude plasma blobs have been studied since their first being reported in 1986. However, investigations on temporal evolution of a blob or on continental scale (\textgreater2,000 km) ionospheric contexts around it are relatively rare. Overcoming these limitations can help elucidate the blob generation mechanisms. On 21 January 2021, the Ionospheric Connection Explorer satellite encountered a typical low-latitude blob near the northeastern coast of South America. The event was collocated with a local enhancement in 135. ...

Park, Jaeheung; Huang, Chao-Song; Eastes, Richard; Coster, Anthea;

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

YEAR: 2022     DOI: 10.1029/2021JA029992

GOLD; ICON; low-latitude plasma blob; Madrigal TEC

Extreme Enhancements of Electron Temperature in Low Latitude Topside Ionosphere During the October 2016 Storm

We use the in-situ observations of DMSP and SWARM satellites to report the changes of the topside ionospheric electron temperature during the October 2016 storm. Electron temperature in the afternoon sector dramatically increases in low latitudes in the recovery phase of the storm. Furthermore, the temperature enhancements have an obvious dependence on longitude and are mainly centralized around 100°–150°E in different satellite observations. The temperature enhancements attain more than 2,000 K at 840 km and 1,500 K at ...

Zhang, Ruilong; Liu, Libo; Ma, Han; Chen, Yiding; Le, Huijun; Yoshikawa, Akimasa;

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

YEAR: 2022     DOI: 10.1029/2022JA030278

electron temperature; equatorial topisde; Ionospheric storm; vertical drift

AMICal Sat: A sparse RGB imager on board a 2U cubesat to study the aurora

AMICal sat, a dedicated 2U cubesat, has been developed, in order to monitor the auroral emissions, with a dedicated imager. It aims to help to reconstruct the low energy electrons fluxes up to 30 keV in Earth auroral regions. It includes an imager entirely designed in Grenoble University Space Center. The imager uses a 1.3 Mpixels sparse RGB CMOS detector and a wide field objective (f=22.5 mm). The satellite platform has been built by the polish company Satrevolution. Launched September, 3rd, 2020 from Kuru (French Guyana) o ...

Barthelemy, Mathieu; Robert, Elisa; Kalegaev, Vladimir; Grennerat, Vincent; Sequies, Thierry; Bourdarot, Guillaume; Le Coarer, Etienne; Correia, Jean-Jacques; Rabou, Patrick;

Published by: IEEE Journal on Miniaturization for Air and Space Systems      Published on:

YEAR: 2022     DOI: 10.1109/JMASS.2022.3187147

Aerospace electronics; AURORA; cubesat; Detectors; imager; Instruments; Ion radiation effects; magnetosphere; Monitoring; Satellites

Interhemispheric Asymmetries in Ionospheric Electron Density Responses During Geomagnetic Storms: A Study Using Space-Based and Ground-Based GNSS and AMPERE Observations

We utilize Total Electron Content (TEC) measurements and electron density (Ne) retrieval profiles from Global Navigation Satellite System (GNSS) receivers onboard multiple Low Earth Orbit (LEO) satellites to characterize large-scale ionosphere-thermosphere system responses during geomagnetic storms. We also analyze TEC measurements from GNSS receivers in a worldwide ground-based network. Measurements from four storms during June and July 2012 (boreal summer months), December 2015 (austral summer month), and March 2015 (equin ...

Swarnalingam, N.; Wu, D.; Gopalswamy, N.;

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

YEAR: 2022     DOI: 10.1029/2021JA030247

Pronounced Suppression and X-Pattern Merging of Equatorial Ionization Anomalies After the 2022 Tonga Volcano Eruption

Following the 2022 Tonga Volcano eruption, dramatic suppression and deformation of the equatorial ionization anomaly (EIA) crests occurred in the American sector ∼14,000 km away from the epicenter. The EIA crests variations and associated ionosphere-thermosphere disturbances were investigated using Global Navigation Satellite System total electron content data, Global-scale Observations of the Limb and Disk ultraviolet images, Ionospheric Connection Explorer wind data, and ionosonde observations. The main results are as fo ...

Aa, Ercha; Zhang, Shun-Rong; Wang, Wenbin; Erickson, Philip; Qian, Liying; Eastes, Richard; Harding, Brian; Immel, Thomas; Karan, Deepak; Daniell, Robert; Coster, Anthea; Goncharenko, Larisa; Vierinen, Juha; Cai, Xuguang; Spicher, Andres;

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

YEAR: 2022     DOI: 10.1029/2022JA030527

EIA suppression and X-pattern; Equatorial ionization anomaly; GNSS TEC; GOLD UV images; ICON MIGHTI neutral wind; Tonga volcano eruption

Ionospheric Disturbances and Irregularities during the 25--26 August 2018 Geomagnetic Storm

We use ground-based (GNSS, SuperDARN, and ionosondes) and space-borne (Swarm, CSES, and DMSP) instruments to study ionospheric disturbances due to the 25–26 August 2018 geomagnetic storm. The strongest large-scale storm-time enhancements were detected over the Asian and Pacific regions during the main and early recovery phases of the storm. In the American sector, there occurred the most complex effects caused by the action of multiple drivers. At the beginning of the storm, a large positive disturbance occurred over North ...

Astafyeva, E.; Yasyukevich, Y.; Maletckii, B.; Oinats, A.; Vesnin, A.; Yasyukevich, A.; Syrovatskii, S.; Guendouz, N.;

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

YEAR: 2022     DOI: 10.1029/2021JA029843

Geomagnetic storms; Ionosphere; ROTI; ionospheric disturbances; ionospheric irregularities; multi-instrumental approach

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-proporti ...

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

Diurnal and Seasonal Characteristics of the Longitudinal Variations of Electron Densities in the Topside Ionosphere at Middle Latitudes

The ionosphere experiences strong diurnal and seasonal changes. The longitudinal variations of electron density (Ne) in the ionosphere at the middle latitudes also show strong diurnal and seasonal changes. In this paper, we use in situ Ne measurements from the DEMETER satellite and electron density profiles retrieved from the COSMIC data to study the local time (LT) and seasonal dependence of the longitudinal variations of topside Ne at middle latitudes during 2007–2009. With regard to the diurnal trend, the reversal phase ...

Su, Fanfan; Wang, Wenbin;

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

YEAR: 2022     DOI: 10.1029/2022JA030308

Electron density; middle latitude; season; topside ionosphere

Ionospheric Disturbances in Low- and Midlatitudes During the Geomagnetic Storm on 26 August 2018

Plasma density depletions at midlatitudes during geomagnetic storms are often understood in terms of equatorial plasma bubbles (EPBs) due to their morphological similarity. However, our study reports the observations that reveal the generation of plasma depletions at midlatitudes by local sources. During the geomagnetic storm on 26 August 2018, the Defense Meteorological Satellite Program and Swarm satellites detected plasma depletions at midlatitudes in the Asian sector in the absence of EPBs in the equatorial region. This ...

Chang, Hyeyeon; Kil, Hyosub; Sun, Andrew; Zhang, Shun-Rong; Lee, Jiyun;

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

YEAR: 2022     DOI: 10.1029/2021JA029879

Impact of Soft Electron Precipitation on the Thermospheric Neutral Mass Density During Geomagnetic Storms: GITM Simulations

In this study, the impact of improving soft (0.1–1 keV) electron precipitation on the F-region neutral mass density has been evaluated using the Global Ionosphere Thermosphere Model (GITM). Two types of electron energy spectra having the same total energy flux and average energy but different spectral shapes have been used to specify the electron precipitation in GITM. One is the Maxwellian spectrum and the other is from an empirical model, Auroral Spectrum and High-Latitude Electric field variabilitY (ASHLEY), which provi ...

Zhu, Qingyu; Deng, Yue; Sheng, Cheng; Anderson, Philip; Bukowski, Aaron;

Published by: Geophysical Research Letters      Published on:

YEAR: 2022     DOI: 10.1029/2021GL097260

ASHLEY; GITM; neutral mass density; soft electron precipitation

Coordinated Observations of Rocket Exhaust Depletion: GOLD, Madrigal TEC, and Multiple Low-Earth-Orbit Satellites

A plasma density hole was created in the ionosphere by a rocket launch from Cape Canaveral, Florida near local sunset on 30 August 2020, which is called rocket exhaust depletion (RED). The hole persisted for several hours into the night and was observed in total electron content (TEC) maps, the Global-scale Observations of the Limb and Disk (GOLD) imager, and multiple low-earth-orbit satellites. The RED created a nightglow pit in the GOLD 135.6 nm image. Swarm satellites found that the RED exhibited insignificant changes in ...

Park, Jaeheung; Rajesh, P.; Ivarsen, Magnus; Lin, Charles; Eastes, Richard; Chao, Chi; Coster, Anthea; Clausen, Lasse; Burchill, Johnathan;

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

YEAR: 2022     DOI: 10.1029/2021JA029909

GOLD; Madrigal TEC; COSMIC-2; Norsat-1; rocket exhaust depletion; swarm

Large-Scale Traveling Atmospheric and Ionospheric Disturbances Observed in GUVI With Multi-Instrument Validations

This study presents multi-instrument observations of persistent large-scale traveling ionosphere/atmospheric disturbances (LSTIDs/LSTADs) observed during moderately increased auroral electrojet activity and a sudden stratospheric warming in the polar winter hemisphere. The Global Ultraviolet Imager (GUVI), Gravity field and steady-state Ocean Circulation Explorer, Scanning Doppler Imaging Fabry–Perot Interferometers, and the Poker Flat Incoherent Scatter Radar are used to demonstrate the presence of LSTIDs/LSTADs between 1 ...

Bossert, Katrina; Paxton, Larry; Matsuo, Tomoko; Goncharenko, Larisa; Kumari, Komal; Conde, Mark;

Published by: Geophysical Research Letters      Published on:

YEAR: 2022     DOI: 10.1029/2022GL099901

Model Estimate of the Height of the Lower Limit of Integration when Obtaining the Ratio of the Concentrations of Atomic Oxygen and Molecular Nitrogen, n (O)/n (N2), According to the Timed Guvi Observation Technique

The results of the model estimate of the height of the lower limit of integration of the ratio of the concentrations of atomic oxygen and molecular nitrogen (n(O)/n(N2)) in the thermosphere according to observations using the Thermosphere, Ionosphere, and Mesosphere Energetics and Dynamics Global UltraViolet Imager (TIMED GUVI) method are presented.

Klimenko, MV; Klimenko, VV; Yasyukevich, AS; Ratovsky, KG;

Published by: Russian Journal of Physical Chemistry B      Published on:

YEAR: 2022     DOI: 10.1134/S1990793122030071

Revisiting the November 2004 Superstorm: Lessons from the TIMED/GUVI Limb Observation

We revisited the November 2004 superstorm by analyzing data from TIMED/GUVI, a FUV spectrograph imager. The GUVI 135.6 nm limb radiances at 520-km tangent altitude are mainly due to the O+ and electron radiative recombination and represent the daytime ionosphere density at the altitude. The 135.6 nm radiances clearly showed a signature of ionospheric equatorial arcs and their variations during the November 2004 magnetic superstorm. When an intense eastward Interplanetary Electric Field (IEF) occurred, the dayside equatorial ...

Zhang, Yongliang; Wang, Wenbin; Paxton, Larry; Schaefer, Robert; Huang, Chaosong;

Published by: 44th COSPAR Scientific Assembly. Held 16-24 July      Published on:

YEAR: 2022     DOI:

Geomagnetic and Solar Dependencies of Midlatitude E-Region Irregularity Occurrence Rate: A Climatology Based on Wuhan VHF Radar Observations

By using Wuhan VHF radar, we show the morphological features of E-region field-aligned irregularity (FAI) occurrence at Wuhan during 2015–2020. Statistical results present that E-region FAI occurrence reaches a maximum after sunset in summer season. According to Doppler spectrum features, type-2 irregularity is predominantly observed at Wuhan. In addition, we observed a remarkable correlation between E-region FAI occurrence and geomagnetic activity, which includes periods of positive correlation and negative correlation de ...

Liu, Yi; Zhou, Chen; Xu, Tong; Deng, Zhongxin; Du, Zhitao; Lan, Ting; Tang, Qiong; Zhu, Yunzhou; Wang, Zhuangkai; Zhao, Zhengyu;

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

YEAR: 2022     DOI: 10.1029/2021JA029597

Thermospheric conditions associated with the loss of 40 Starlink satellites

We analyzed far ultraviolet data from Defense Meteorological Satellite Program (DMSP)/Special Sensor Ultraviolet Spectrographic Imager (SSUSI) and Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED)/Global Ultraviolet Imager (GUVI) and found significant changes in the thermospheric density and composition during the 3–5 February 2022 storm when 40 Starlink satellites started to re-enter the atmosphere associated with increased neutral drag at an altitude around 210 km. The standard NRLMSISE-00 model predicts ...

Zhang, Yongliang; Paxton, Larry; Schaefer, Robert; Swartz, William;

Published by: Space Weather      Published on:

YEAR: 2022     DOI: 10.1029/2022SW003168

Ionospheric effects of a solar wind high-speed stream driven geomagnetic storm

Solar wind high-speed streams (HSSs) and associated stream interaction regions (SIRs) typically produce long-lasting, but only moderate or weak geomagnetic storms. In this presentation, we will focus on electron density (Ne) and total electron content (TEC) changes at high to middle latitudes and associated physical processes during a specific HSS/SIR driven storm. The very long-lasting storm was produced by two interacting high-speed streams. Both enhancements, but in specific long-lasting (days) decreases of Ne and TEC are ...

Aikio, Anita;

Published by: 44th COSPAR Scientific Assembly. Held 16-24 July      Published on:

YEAR: 2022     DOI:

Aspects related to variability of radiative cooling by NO in lower thermosphere, TEC and O/N2 correlation, and diffusion of NO into mesosphere during the Halloween storms

Nitric Oxide is a very important trace species which plays a significant role acting as a natural thermostat in Earth’s thermosphere during strong geomagnetic activity. In this paper, we present various aspects related to the variation in the NO Infrared radiative flux (IRF) exiting the thermosphere by utilizing the TIMED/SABER (Thermosphere Ionosphere Mesosphere Energetics and Dynamics/ Sounding of the Atmosphere using Broadband Emission Radiometry) observational data during the Halloween storm which occurred in late Octo ...

Ranjan, Alok; Krishna, MV; Kumar, Akash; Sarkhel, Sumanta; Bharti, Gaurav; Bender, Stefan; Sinnhuber, Miriam;

Published by: Advances in Space Research      Published on:

YEAR: 2022     DOI: 10.1016/j.asr.2022.07.035

The Global Response of Terrestrial Ionosphere to the December 2015 Space Weather Event

This paper investigates the ionospheric storm of December 19–21, 2015, which was initiated by two successive CME eruptions that caused a G3 space weather event. We used the in situ electron density (Ne) and electron temperature (Te) and the Total Electron Content (TEC) measurements from SWARM-A satellite, as well as the O/N2 observations from TIMED/GUVI to study the ionospheric impact. The observations reveal the longitudinal and hemispherical differences in the ionospheric response to the storm event. A positive ionospher ...

Thampi, Smitha; Mukundan, Vrinda;

Published by: Advances in Space Research      Published on:

YEAR: 2022     DOI: 10.1016/j.asr.2022.10.037

Climatology of O/N2 Variations at Low-and Mid-Latitudes during Solar Cycles 23 and 24

We present a study concerning the thermospheric O/N2 variations for the period 2002 to 2020, using the measurements of global ultraviolet imager (GUVI) onboard TIMED satellite. In this regard, monthly averaged O/N2 was computed—using the five quietest days of the month—at low- and mid-latitudes. To find the longitudinal dependence of thermospheric variations, the analysis is further extended to different longitudinal sectors, namely Asia, Africa, and America. We found that the latitudinal and longitudinal O/N2 variations ...

Khan, Jahanzeb; Younas, Waqar; Khan, Majid; Amory-Mazaudier, Christine;

Published by: Atmosphere      Published on:

YEAR: 2022     DOI: 10.3390/atmos13101645

Solar cycle, seasonal, and dawn-to-dusk variations of the hydrogen in the upper thermosphere

Atomic hydrogen is one of the least-understood atmospheric constituents whose distribution is important for the studies of aeronomy and magnetospheric physics. Using 6 years of space-based daytime Lyman-α observations from 2002 to 2007, we quantify the solar cycle, seasonal, and dawn-to-dusk variations of the H density in the upper thermosphere. Our results show evident dawn-dusk asymmetry of the exobase H density that decreases nearly linearly from dawn to dusk. The observed asymmetry in terms of the dawn-dusk density rati ...

Wan, Changan; Qin, Jianqi; Paxton, Larry;

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

YEAR: 2022     DOI: 10.1029/2022JA030504

Ionospheric Response to the 23-31 August 2018 Geomagnetic Storm in the Europe-African Longitude Sector Using Multi-Instrument Observations

This study presents ionospheric responses of the mid and low-latitude region in the Europe-African longitude sector (along 30 +/- 10 deg E) to the intense geomagnetic storm of 23–31 August 2018 (SYM-Hmin = −207 nT) using the Global Ionospheric Map (GIM) and Global Positioning System (GPS) receivers data, the satellite data (SWARM, Defense Meteorological Satellite Program (DMSP), Global Ultraviolet Imager on board the Thermosphere, Ionosphere, Mesosphere Energetics and Dynamics (GUVI/TIMED)), and Prompt Penetration Equato ...

Dugassa, Teshome; Mezgebe, Nigussie; Habarulema, John; Habyarimana, Valence; Oljira, Asebe;

Published by: Advances in Space Research      Published on:

YEAR: 2022     DOI: 10.1016/j.asr.2022.10.063



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