Bibliography

Was Magnetic Storm the Only Driver of the Long-Duration Enhancements of Daytime Total Electron Content in the Asian-Australian Sector Between 7 and 12 September 2017?

In this study, multiple data sets from Beidou geostationary orbit satellites total electron contents (TECs), ionosonde, meteor radar, magnetometer, and model simulations have been used to investigate the ionospheric responses in the Asian-Australian sector during the September 2017 geomagnetic storm. It was found that long-duration daytime TEC enhancements that lasted from 7 to 12 September 2017 were observed by the Beidou geostationary orbit satellite constellation. This is a unique event as the prominent TEC enhancements persisted during the storm recovery phase when geomagnetic activity became quiet. The Thermosphere-Ionosphere Electrodynamics Global Circulation Model predicted that the TEC enhancements on 7\textendash9 September were associated with the geomagnetic activity, but it showed significant electron density depletions on 10 and 11 September in contrast to the observed TEC enhancements. Our results suggested that the observed long-duration TEC enhancements from 7 to 12 September are mainly associated with the interplay of ionospheric dynamics and electrodynamics. Nevertheless, the root causes for the observed TEC enhancements seen in the storm recovery phase are unknown and require further observations and model studies.

Lei, Jiuhou; Huang, Fuqing; Chen, Xuetao; Zhong, Jiahao; Ren, Dexin; Wang, Wenbin; Yue, Xinan; Luan, Xiaoli; Jia, Mingjiao; Dou, Xiankang; Hu, Lianhuan; Ning, Baiqi; Owolabi, Charles; Chen, Jinsong; Li, Guozhu; Xue, Xianghui;

Published by: Journal of Geophysical Research: Space Physics Published on: 04/2018

YEAR: 2018 DOI: 10.1029/2017JA025166

Four-peak longitudinal distribution of the equatorial plasma bubbles observed in the topside ionosphere: Possible troposphere tide influence

In this paper we consider an idea of the troposphere tide influence on the character of the longitudinal variations in the distribution of the equatorial plasma bubbles (EPBs) observed in the topside ionosphere. For this purpose, the obtained EPB longitudinal patterns were compared with the thermosphere and ionosphere characteristics having the prominent “wave-like” longitudinal structures with wave number 4, which are uniquely associated with the influence of the troposphere DE3 tides. The characteristics of the equatorial mass density anomaly (EMA), equatorial ionization anomaly (EIA), zonal wind and pre-reversal E × B drift enhancement (PRE) were used for comparison. The equinox seasons during high solar activity were under consideration. It was obtained that the longitudinal patterns of the EMA and zonal wind show the surprising similarity with the EPB distributions (R ~ 0.8, R ~ 0.72). On the other hand, the resemblance with the ionosphere characteristics (EIA, PRE) is rather faint (R ~ 0.37, R~ 0.12). It was shown that the thermosphere zonal winds are the most possible transfer mediator of the troposphere DE3 tide influence. The most successful moment for the transfer of the troposphere DE3 tide energy takes place in the beginning of the EPB production, namely, during the seed perturbation development.

Sidorova, L.N.; Filippov, S.V.;

Published by: Advances in Space Research Published on: 03/2018

YEAR: 2018 DOI: 10.1016/j.asr.2017.12.035

Development and Validation of the Whole Atmosphere Community Climate Model With Thermosphere and Ionosphere Extension (WACCM-X 2.0)

Key developments have been made to the NCAR Whole Atmosphere Community Climate Model with thermosphere and ionosphere extension (WACCM-X). Among them, the most important are the self-consistent solution of global electrodynamics, and transport of O⁺ in the F-region. Other ionosphere developments include time-dependent solution of electron/ion temperatures, metastable O⁺ chemistry, and high-cadence solar EUV capability. Additional developments of the thermospheric components are improvements to the momentum and energy equation solvers to account for variable mean molecular mass and specific heat, a new divergence damping scheme, and cooling by O(³P) fine structure. Simulations using this new version of WACCM-X (2.0) have been carried out for solar maximum and minimum conditions. Thermospheric composition, density, and temperatures are in general agreement with measurements and empirical models, including the equatorial mass density anomaly and the midnight density maximum. The amplitudes and seasonal variations of atmospheric tides in the mesosphere and lower thermosphere are in good agreement with observations. Although global mean thermospheric densities are comparable with observations of the annual variation, they lack a clear semiannual variation. In the ionosphere, the low-latitude E \texttimes B drifts agree well with observations in their magnitudes, local time dependence, seasonal, and solar activity variations. The prereversal enhancement in the equatorial region, which is associated with ionospheric irregularities, displays patterns of longitudinal and seasonal variation that are similar to observations. Ionospheric density from the model simulations reproduces the equatorial ionosphere anomaly structures and is in general agreement with observations. The model simulations also capture important ionospheric features during storms.

Liu, Han-Li; Bardeen, Charles; Foster, Benjamin; Lauritzen, Peter; Liu, Jing; Lu, Gang; Marsh, Daniel; Maute, Astrid; McInerney, Joseph; Pedatella, Nicholas; Qian, Liying; Richmond, Arthur; Roble, Raymond; Solomon, Stanley; Vitt, Francis; Wang, Wenbin;

Published by: Journal of Advances in Modeling Earth Systems Published on: 01/2018

YEAR: 2018 DOI: 10.1002/jame.v10.210.1002/2017MS001232

Development and Validation of the Whole Atmosphere Community Climate Model With Thermosphere and Ionosphere Extension (WACCM-X 2.0)

Key developments have been made to the NCAR Whole Atmosphere Community Climate Model with thermosphere and ionosphere extension (WACCM-X). Among them, the most important are the self-consistent solution of global electrodynamics, and transport of O⁺ in the F-region. Other ionosphere developments include time-dependent solution of electron/ion temperatures, metastable O⁺ chemistry, and high-cadence solar EUV capability. Additional developments of the thermospheric components are improvements to the momentum and energy equation solvers to account for variable mean molecular mass and specific heat, a new divergence damping scheme, and cooling by O(³P) fine structure. Simulations using this new version of WACCM-X (2.0) have been carried out for solar maximum and minimum conditions. Thermospheric composition, density, and temperatures are in general agreement with measurements and empirical models, including the equatorial mass density anomaly and the midnight density maximum. The amplitudes and seasonal variations of atmospheric tides in the mesosphere and lower thermosphere are in good agreement with observations. Although global mean thermospheric densities are comparable with observations of the annual variation, they lack a clear semiannual variation. In the ionosphere, the low-latitude E \texttimes B drifts agree well with observations in their magnitudes, local time dependence, seasonal, and solar activity variations. The prereversal enhancement in the equatorial region, which is associated with ionospheric irregularities, displays patterns of longitudinal and seasonal variation that are similar to observations. Ionospheric density from the model simulations reproduces the equatorial ionosphere anomaly structures and is in general agreement with observations. The model simulations also capture important ionospheric features during storms.

Liu, Han-Li; Bardeen, Charles; Foster, Benjamin; Lauritzen, Peter; Liu, Jing; Lu, Gang; Marsh, Daniel; Maute, Astrid; McInerney, Joseph; Pedatella, Nicholas; Qian, Liying; Richmond, Arthur; Roble, Raymond; Solomon, Stanley; Vitt, Francis; Wang, Wenbin;

Published by: Journal of Advances in Modeling Earth Systems Published on: 01/2018

YEAR: 2018 DOI: 10.1002/jame.v10.210.1002/2017MS001232

Temporal Variability of Atomic Hydrogen From the Mesopause to the Upper Thermosphere

We investigate atomic hydrogen (H) variability from the mesopause to the upper thermosphere, on time scales of solar cycle, seasonal, and diurnal, using measurements made by the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument on the Thermosphere Ionosphere Mesosphere Energetics Dynamics satellite, and simulations by the National Center for Atmospheric Research Whole Atmosphere Community Climate Model-eXtended (WACCM-X). In the mesopause region (85 to 95\ km), the seasonal and solar cycle variations of H simulated by WACCM-X are consistent with those from SABER observations: H density is higher in summer than in winter, and slightly higher at solar minimum than at solar maximum. However, mesopause region H density from the Mass-Spectrometer-Incoherent-Scatter (National Research Laboratory Mass-Spectrometer-Incoherent-Scatter 00 (NRLMSISE-00)) empirical model has reversed seasonal variation compared to WACCM-X and SABER. From the mesopause to the upper thermosphere, H density simulated by WACCM-X switches its solar cycle variation twice, and seasonal dependence once, and these changes of solar cycle and seasonal variability occur in the lower thermosphere (~95 to 130\ km), whereas H from NRLMSISE-00 does not change solar cycle and seasonal dependence from the mesopause through the thermosphere. In the upper thermosphere (above 150\ km), H density simulated by WACCM-X is higher at solar minimum than at solar maximum, higher in winter than in summer, and also higher during nighttime than daytime. The amplitudes of these variations are on the order of factors of ~10, ~2, and ~2, respectively. This is consistent with NRLMSISE-00.

Qian, Liying; Burns, Alan; Solomon, Stan; Smith, Anne; McInerney, Joseph; Hunt, Linda; Marsh, Daniel; Liu, Hanli; Mlynczak, Martin; Vitt, Francis;

Published by: Journal of Geophysical Research: Space Physics Published on: 01/2018

YEAR: 2018 DOI: 10.1002/2017JA024998

Features of High-Lat Ionospheric Irregularities Development as Revealed by Ground-Based GPS Observations, Satellite-Borne GPS Observations and Satellite In Situ Measurements over the Territory of Russia during the Geomagnetic Storm on March 17-18, 2015

The dynamic picture of the response of the high- and mid-latitude ionosphere to the strong geomagnetic disturbances on March 17-18, 2015, has been studied with ground-based and satellite observations, mainly, by transionospheric measurements of delays of GPS (Global Positioning System) signals. The advantages of the joint use of ground-based GPS measurements and GPS measurements on board of the Swarm Low-Earth-Orbit satellite mission for monitoring of the appearance of ionospheric irregularities over the territory of Russia are shown for the first time. The results of analysis of ground-based and space-borne GPS observations, as well as satellite, in situ measurements, revealed large-scale ionospheric plasma irregularities observed over the territory of Russia in the latitude range of 50^o - 85^o N during the main phase of the geomagnetic storm. The most intense ionospheric irregularities were detected in the auroral zone and in the region of the main ionospheric trough (MIT). It has been found that sharp changes in the phase of the carrier frequency of the navigation signal from all tracked satellites were recorded at all GPS stations located to the North from 55^o MLAT. The development of a deep MIT was related to dynamic processes in the subauroral ionosphere, in particular, with electric fields of the intense subauroral polarization stream. Analysis of the electron and ion density values obtained by instruments on board of the Swarm and DMSP satellites showed that the zone of highly structured auroral ionosphere extended at least to heights of 850-900 km.

Zakharenkova, I.; Cherniak, Iu.; Shagimuratov, I.; Klimenko, M.;

Published by: Geomagnetism and Aeronomy Published on: 01/2018

YEAR: 2018 DOI: 10.1134/S0016793217050176

Global-scale Observations of the Limb and Disk (GOLD): science implementation

McClintock, William; Eastes, Richard; Andersson, Laila; Burns, Alan; Codrescu, Mihail; Daniell, Robert; England, Scott; Evans, Scott; Krywonos, Andrey; Lumpe, Jerry; , others;

Published by: Published on:

YEAR: 2018 DOI:

Nighttime enhancement of midlatitude ionosphere and its connection to the plasmasphere

Hao, Yongqiang; Zhang, Donghe; Xiao, Zuo; Li, Quanhan;

Published by: 42nd COSPAR Scientific Assembly Published on:

YEAR: 2018 DOI:

Winter anomaly in NmF2 and TEC: when and where it can occur

Yasyukevich, Yury; Yasyukevich, Anna; Ratovsky, Konstantin; Klimenko, Maxim; Klimenko, Vladimir; Chirik, Nikolay;

Published by: Journal of Space Weather and Space Climate Published on:

YEAR: 2018 DOI:

Winter anomaly in NmF2 and TEC: when and where it can occur

Yasyukevich, Yury; Yasyukevich, Anna; Ratovsky, Konstantin; Klimenko, Maxim; Klimenko, Vladimir; Chirik, Nikolay;

Published by: Journal of Space Weather and Space Climate Published on:

YEAR: 2018 DOI:

How might the thermosphere and ionosphere react to an extreme space weather event?

This chapter explores how the thermosphere and ionosphere (T-I) might respond to extreme solar events. Three different scenarios are considered: (1) an increase in solar UV and EUV radiation for a number of days, (2) an extreme enhancement in the solar X-rays and EUV radiation associated with a flare, and (3) an extreme CME driving a geomagnetic storm. Estimating the response to the first two scenarios is reasonably well defined, and although they would certainly impact the T-I system, those impacts could potentially be mitigated. In contrast, the response to an extreme geomagnetic storm is significantly more complicated, making the response much more uncertain, and mitigation more challenging.

Fuller-Rowell, Tim; Emmert, John; Fedrizzi, Mariangel; Weimer, Daniel; Codrescu, Mihail; Pilinski, Marcin; Sutton, Eric; Viereck, Rodney; Raeder, Joachim; Doornbos, Eelco;

Published by: Published on:

YEAR: 2018 DOI: 10.1016/B978-0-12-812700-1.00021-2

Comparison of the Thermospheric Nitric Oxide Emission Observations and the Global Ionosphere-Thermosphere Model (GITM) Simulations: Sensitivity to Solar and Geomagnetic Activities

The magnitude of enhancement observed in column density agrees well with the cases observed by TIMED/GUVI −8 W/m3) agree well with TIMED/SABER and GUVI measurements.

Lin, Cissi; Deng, Yue; Venkataramani, Karthik; Yonker, Justin; Bailey, Scott;

Published by: arXiv preprint arXiv:1807.01380 Published on:

YEAR: 2018 DOI: https://doi.org/10.48550/arXiv.1807.01380

The ionospheric connection explorer mission: Mission goals and design

The Ionospheric Connection Explorer, or ICON, is a new NASA Explorer mission that will explore the boundary between Earth and space to understand the physical connection

Immel, Thomas; England, SL; Mende, SB; Heelis, RA; Englert, CR; Edelstein, J; Frey, HU; Korpela, EJ; Taylor, ER; Craig, WW; , others;

Published by: Space Science Reviews Published on:

YEAR: 2018 DOI: 10.1007/s11214-017-0449-2

Chinese ionospheric investigations in 2016—2017

After the release of the previous report to the Committee on Space Research (COSPAR) on progress achieved by Chinese scientists in ionospheric researches (Liu LB and Wan WX

Liu, Libo; Wan, Weixing;

Published by: Earth and Planetary Physics Published on:

YEAR: 2018 DOI: 10.26464/epp2018011

Whole Atmosphere Community Climate Model—eXtended Version 2.0 Scientific Description

Key developments have been made to the NCAR Whole Atmosphere Community Climate Model with thermosphere and ionosphere extension (WACCM-X). Among them the most

Liu, Han-Li; Bardeen, Charles; Foster, Benjamin; Lauritzen, Peter; Liu, Jing; Lu, Gang; Marsh, Daniel; Maute, Astrid; McInerney, Joseph; Pedatella, Nicholas; , others;

Published by: Published on:

YEAR: 2018 DOI:

Whole Atmosphere Community Climate Model—eXtended Version 2.0 Scientific Description

Key developments have been made to the NCAR Whole Atmosphere Community Climate Model with thermosphere and ionosphere extension (WACCM-X). Among them the most

Liu, Han-Li; Bardeen, Charles; Foster, Benjamin; Lauritzen, Peter; Liu, Jing; Lu, Gang; Marsh, Daniel; Maute, Astrid; McInerney, Joseph; Pedatella, Nicholas; , others;

Published by: Published on:

YEAR: 2018 DOI:

Inferring nighttime ionospheric parameters with the far ultraviolet imager onboard the ionospheric connection explorer

The Ionospheric Connection Explorer (ICON) Far Ultraviolet (FUV) imager, ICON FUV, will measure altitude profiles of OI 135.6 nm emissions to infer nighttime ionospheric parameters.

Kamalabadi, Farzad; Qin, Jianqi; Harding, Brian; Iliou, Dimitrios; Makela, Jonathan; Meier, RR; England, Scott; Frey, Harald; Mende, Stephen; Immel, Thomas;

Published by: Space science reviews Published on:

YEAR: 2018 DOI:

The statistic characteristics of HF Oblique Sounding Channel at mid and low latitude during ionospheric disturbance time

In this study, historical data MOFF from two HF propagation paths: Qingdao-Lanzhou and Guangzhou-Haikou at mid and low latitude, the midpoint referenced data are from two

Wang, Fei-Fei; Liu, Yu-Mei; Sun, Shu-Ji;

Published by: Published on:

YEAR: 2018 DOI: 10.1109/ISAPE.2018.8634091

Statistical Comparison of Auroras in Northern and Southern Hemispheres

Liou, Kan; , others;

Published by: Published on:

YEAR: 2018 DOI:

Observations and Modeling of Atomic/Molecular Composition in the Thermosphere

Solomon, Stanley; Eastes, Richard; McClintock, William; Paxton, Larry; Zhang, Yongliang;

Published by: Published on:

YEAR: 2018 DOI:

Vertical Coupling in the Ionosphere—Thermosphere System I Posters

Heelis, Roderick; Rowland, Douglas; Paxton, Larry;

Published by: Published on:

YEAR: 2018 DOI:

Interplanetary Magnetic Field By Effects on the Polar Neutral Composition

Liu, Jing; Wang, Wenbin; Burns, Alan;

Published by: Published on:

YEAR: 2018 DOI:

Changes in the Stratosphere and Ionosphere Parameters During the 2013 Major Stratospheric Warming

The paper presents the results of the complex experiment (lidar and ozonometric observations), carried out during the period of the 2013 major sudden stratospheric warming (SSW) in the North Asia region. The data of this experiment were supplemented by the ionospheric parameters observations. We considered variations in the critical frequency and peak height of the ionospheric F2-layer (foF2) from ionosonde measurements in Tomsk and Irkutsk, as well as the behavior of the total electron content (TEC) based on the phase dual-frequency GPS/GLONASS receivers\textquoteright data. We revealed significant variations in the stratosphere ozone concentration, ionospheric electron density, as well as in the thermosphere O/N ₂ ratio with the similar pattern during the SSW. The ionospheric response to SSW in the middle and high-latitude regions is suggested to be caused by changes in the neutral composition at the thermosphere altitudes.

Yasyukevich, Anna; Kulikov, Yury; Klimenko, Maxim; Klimenko, Vladimir; Bessarab, Fedor; Korenkov, Yury; Marichev, Valery; Ratovsky, Konstantin; Kolesnik, Sergey;

Published by: Published on:

YEAR: 2018 DOI: 10.23919/URSI-AT-RASC.2018.8471322

Changes in the Stratosphere and Ionosphere Parameters During the 2013 Major Stratospheric Warming

The paper presents the results of the complex experiment (lidar and ozonometric observations), carried out during the period of the 2013 major sudden stratospheric warming (SSW) in the North Asia region. The data of this experiment were supplemented by the ionospheric parameters observations. We considered variations in the critical frequency and peak height of the ionospheric F2-layer (foF2) from ionosonde measurements in Tomsk and Irkutsk, as well as the behavior of the total electron content (TEC) based on the phase dual-frequency GPS/GLONASS receivers\textquoteright data. We revealed significant variations in the stratosphere ozone concentration, ionospheric electron density, as well as in the thermosphere O/N ₂ ratio with the similar pattern during the SSW. The ionospheric response to SSW in the middle and high-latitude regions is suggested to be caused by changes in the neutral composition at the thermosphere altitudes.

Yasyukevich, Anna; Kulikov, Yury; Klimenko, Maxim; Klimenko, Vladimir; Bessarab, Fedor; Korenkov, Yury; Marichev, Valery; Ratovsky, Konstantin; Kolesnik, Sergey;

Published by: Published on:

YEAR: 2018 DOI: 10.23919/URSI-AT-RASC.2018.8471322

Changes in the Stratosphere and Ionosphere Parameters During the 2013 Major Stratospheric Warming

The paper presents the results of the complex experiment (lidar and ozonometric observations), carried out during the period of the 2013 major sudden stratospheric warming (SSW) in the North Asia region. The data of this experiment were supplemented by the ionospheric parameters observations. We considered variations in the critical frequency and peak height of the ionospheric F2-layer (foF2) from ionosonde measurements in Tomsk and Irkutsk, as well as the behavior of the total electron content (TEC) based on the phase dual-frequency GPS/GLONASS receivers\textquoteright data. We revealed significant variations in the stratosphere ozone concentration, ionospheric electron density, as well as in the thermosphere O/N ₂ ratio with the similar pattern during the SSW. The ionospheric response to SSW in the middle and high-latitude regions is suggested to be caused by changes in the neutral composition at the thermosphere altitudes.

Yasyukevich, Anna; Kulikov, Yury; Klimenko, Maxim; Klimenko, Vladimir; Bessarab, Fedor; Korenkov, Yury; Marichev, Valery; Ratovsky, Konstantin; Kolesnik, Sergey;

Published by: Published on:

YEAR: 2018 DOI: 10.23919/URSI-AT-RASC.2018.8471322

Physical processes driving the thermospheric variations during the March 2015 St. Patrick's day major geomagnetic storm

Wang, Wenbin; Qian, Liying; Burns, Alan; Liu, Jing;

Published by: 42nd COSPAR Scientific Assembly Published on:

YEAR: 2018 DOI:

Reconstruction the Ionospheric Responses to the October-November 2003 Halloween Super Storm: A Data Assimilation Approach

Chang, Yu-Shan; Chen, Chia-Hung; Lin, Charles; Chu, Hung-Hsuan; Matsuo, Tomoko;

Published by: Published on:

YEAR: 2018 DOI:

Vertical Thermospheric Density Profiles From EUV Solar Occultations Made by PROBA2 LYRA for Solar Cycle 24

A new data set of summed neutral N₂ and O number density profiles, spanning altitudes between 150 and 400\ km, and observed during Northern Winter from 2010 to 2016 is presented. The neutral density profiles are derived from solar occultation measurements made by the 0.1\textendash20\ nm Zr channel on the Large Yield Radiometer (LYRA) instrument on board Project for Onboard Autonomy 2 (PROBA2). The climatology derived from the vertical profiles is consistent with that predicted by the NRLMSISE-00 model, and the systematic error and random uncertainty of the measurements are less than 13\% and 6\%, respectively. The density profiles are used to characterize the response of thermospheric density to solar EUV irradiance variability. Peak correlation coefficients between neutral density and EUV irradiance occur near 300\ km at the dusk terminator and 220\ km at the dawn terminator. Density variability is higher at dawn than it is at dusk, and temperature variability increases with increasing altitude at both terminators.

Thiemann, E.; Dominique, M.; Pilinski, M.; Eparvier, F.;

Published by: Space Weather Published on: 12/2017

YEAR: 2017 DOI: 10.1002/2017SW001719

Equatorial ionospheric disturbances over the East African sector during the 2015 St. Patrick\textquoterights day storm

Olwendo, O.J.; Cesaroni, C.; Yamazaki, Y.; Cilliers, P.;

Published by: Advances in Space Research Published on: 10/2017

YEAR: 2017 DOI: 10.1016/j.asr.2017.06.037

The Far Ultra-Violet Imager on the Icon Mission

ICON Far UltraViolet (FUV) imager contributes to the ICON science objectives by providing remote sensing measurements of the daytime and nighttime atmosphere/ionosphere. During sunlit atmospheric conditions, ICON FUV images the limb altitude profile in the shortwave (SW) band at 135.6 nm and the longwave (LW) band at 157 nm perpendicular to the satellite motion to retrieve the atmospheric O/N₂ ratio. In conditions of atmospheric darkness, ICON FUV measures the 135.6 nm recombination emission of O+ ions used to compute the nighttime ionospheric altitude distribution. ICON Far UltraViolet (FUV) imager is a Czerny\textendashTurner design Spectrographic Imager with two exit slits and corresponding back imager cameras that produce two independent images in separate wavelength bands on two detectors. All observations will be processed as limb altitude profiles. In addition, the ionospheric 135.6 nm data will be processed as longitude and latitude spatial maps to obtain images of ion distributions around regions of equatorial spread F. The ICON FUV optic axis is pointed 20 degrees below local horizontal and has a steering mirror that allows the field of view to be steered up to 30 degrees forward and aft, to keep the local magnetic meridian in the field of view. The detectors are micro channel plate (MCP) intensified FUV tubes with the phosphor fiber-optically coupled to Charge Coupled Devices (CCDs). The dual stack MCP-s amplify the photoelectron signals to overcome the CCD noise and the rapidly scanned frames are co-added to digitally create 12-second integrated images. Digital on-board signal processing is used to compensate for geometric distortion and satellite motion and to achieve data compression. The instrument was originally aligned in visible light by using a special grating and visible cameras. Final alignment, functional and environmental testing and calibration were performed in a large vacuum chamber with a UV source. The test and calibration program showed that ICON FUV meets its design requirements and is ready to be launched on the ICON spacecraft.

Mende, S.; Frey, H.; Rider, K.; Chou, C.; Harris, S.; Siegmund, O.; England, S.; Wilkins, C.; Craig, W.; Immel, T.; Turin, P.; Darling, N.; Loicq, J.; Blain, P.; Syrstad, E.; Thompson, B.; Burt, R.; Champagne, J.; Sevilla, P.; Ellis, S.;

Published by: Space Science Reviews Published on: 10/2017

YEAR: 2017 DOI: 10.1007/s11214-017-0386-0

The Far Ultra-Violet Imager on the Icon Mission

ICON Far UltraViolet (FUV) imager contributes to the ICON science objectives by providing remote sensing measurements of the daytime and nighttime atmosphere/ionosphere. During sunlit atmospheric conditions, ICON FUV images the limb altitude profile in the shortwave (SW) band at 135.6 nm and the longwave (LW) band at 157 nm perpendicular to the satellite motion to retrieve the atmospheric O/N₂ ratio. In conditions of atmospheric darkness, ICON FUV measures the 135.6 nm recombination emission of O+ ions used to compute the nighttime ionospheric altitude distribution. ICON Far UltraViolet (FUV) imager is a Czerny\textendashTurner design Spectrographic Imager with two exit slits and corresponding back imager cameras that produce two independent images in separate wavelength bands on two detectors. All observations will be processed as limb altitude profiles. In addition, the ionospheric 135.6 nm data will be processed as longitude and latitude spatial maps to obtain images of ion distributions around regions of equatorial spread F. The ICON FUV optic axis is pointed 20 degrees below local horizontal and has a steering mirror that allows the field of view to be steered up to 30 degrees forward and aft, to keep the local magnetic meridian in the field of view. The detectors are micro channel plate (MCP) intensified FUV tubes with the phosphor fiber-optically coupled to Charge Coupled Devices (CCDs). The dual stack MCP-s amplify the photoelectron signals to overcome the CCD noise and the rapidly scanned frames are co-added to digitally create 12-second integrated images. Digital on-board signal processing is used to compensate for geometric distortion and satellite motion and to achieve data compression. The instrument was originally aligned in visible light by using a special grating and visible cameras. Final alignment, functional and environmental testing and calibration were performed in a large vacuum chamber with a UV source. The test and calibration program showed that ICON FUV meets its design requirements and is ready to be launched on the ICON spacecraft.

Mende, S.; Frey, H.; Rider, K.; Chou, C.; Harris, S.; Siegmund, O.; England, S.; Wilkins, C.; Craig, W.; Immel, T.; Turin, P.; Darling, N.; Loicq, J.; Blain, P.; Syrstad, E.; Thompson, B.; Burt, R.; Champagne, J.; Sevilla, P.; Ellis, S.;

Published by: Space Science Reviews Published on: 10/2017

YEAR: 2017 DOI: 10.1007/s11214-017-0386-0

The Global-Scale Observations of the Limb and Disk (GOLD) Mission

The Earth\textquoterights thermosphere and ionosphere constitute a dynamic system that varies daily in response to energy inputs from above and from below. This system can exhibit a significant response within an hour to changes in those inputs, as plasma and fluid processes compete to control its temperature, composition, and structure. Within this system, short wavelength solar radiation and charged particles from the magnetosphere deposit energy, and waves propagating from the lower atmosphere dissipate. Understanding the global-scale response of the thermosphere-ionosphere (T-I) system to these drivers is essential to advancing our physical understanding of coupling between the space environment and the Earth\textquoterights atmosphere. Previous missions have successfully determined how the \textquotedblleftclimate\textquotedblright of the T-I system responds. The Global-scale Observations of the Limb and Disk (GOLD) mission will determine how the \textquotedblleftweather\textquotedblright of the T-I responds, taking the next step in understanding the coupling between the space environment and the Earth\textquoterights atmosphere. Operating in geostationary orbit, the GOLD imaging spectrograph will measure the Earth\textquoterights emissions from 132 to 162 nm. These measurements will be used image two critical variables\textemdashthermospheric temperature and composition, near 160 km\textemdashon the dayside disk at half-hour time scales. At night they will be used to image the evolution of the low latitude ionosphere in the same regions that were observed earlier during the day. Due to the geostationary orbit being used the mission observes the same hemisphere repeatedly, allowing the unambiguous separation of spatial and temporal variability over the Americas.

Eastes, R.; McClintock, W.; Burns, A.; Anderson, D.; Andersson, L.; Codrescu, M.; Correira, J.; Daniell, R.; England, S.; Evans, J.; Harvey, J.; Krywonos, A.; Lumpe, J.; Richmond, A.; Rusch, D.; Siegmund, O.; Solomon, S.; Strickland, D.; Woods, T.; Aksnes, A.; Budzien, S.; Dymond, K.; Eparvier, F.; Martinis, C.; Oberheide, J.;

Published by: Space Science Reviews Published on: 10/2017

YEAR: 2017 DOI: 10.1007/s11214-017-0392-2

The Storm Time Evolution of the Ionospheric Disturbance Plasma Drifts

In this paper, we use the C/NOFS and ROCSAT-1 satellites observations to analyze the storm time evolution of the disturbance plasma drifts in a 24\ h local time scale during three magnetic storms driven by long-lasting southward IMF B_z. The disturbance plasma drifts during the three storms present some common features in the periods dominated by the disturbance dynamo. The newly formed disturbance plasma drifts are upward and westward at night, and downward and eastward during daytime. Further, the disturbance plasma drifts are gradually evolved to present significant local time shifts. The westward disturbance plasma drifts gradually migrate from nightside to dayside. Meanwhile, the dayside downward disturbance plasma drifts become enhanced and shift to later local time. The local time shifts in disturbance plasma drifts are suggested to be mainly attributed to the evolution of the disturbance winds. The strong disturbance winds arisen around midnight can constantly corotate to later local time. At dayside the westward and equatorward disturbance winds can drive the F region dynamo to produce the poleward and westward polarization electric fields (or the westward and downward disturbance drifts). The present results indicate that the disturbance winds corotated to later local time can affect the local time features of the disturbance dynamo electric field.

Zhang, Ruilong; Liu, Libo; Le, Huijun; Chen, Yiding; Kuai, Jiawei;

Published by: Journal of Geophysical Research: Space Physics Published on: 10/2017

YEAR: 2017 DOI: 10.1002/2017JA024637

The non--storm time corrugated upper thermosphere: What is beyond MSIS?

Observations in the recent decade have revealed many thermospheric density corrugations/perturbations under nonstorm conditions (Kp \< 2). They are generally not captured by empirical models like Mass Spectrometer Incoherent Scatter (MSIS) but are operationally important for long-term orbital evolution of Low Earth Orbiting satellites and theoretically for coupling processes in the atmosphere-ionosphere system. We review these density corrugations by classifying them into three types which are driven respectively by the lower atmosphere, ionosphere, and solar wind/magnetosphere. Model capabilities in capturing these features are discussed. A summary table of these corrugations is included to provide a quick guide on their magnitudes, occurring latitude, local time, and season.

Liu, Huixin; Thayer, Jeff; Zhang, Yongliang; Lee, Woo;

Published by: Space Weather Published on: 06/2017

YEAR: 2017 DOI: 10.1002/swe.v15.610.1002/2017SW001618

A severe negative response of the ionosphere to the intense geomagnetic storm on March 17, 2015 observed at mid- and low-latitude stations in the China zone

In this paper, the critical frequency of F2 layer of the ionosphere (foF₂₎ and the total electron content (TEC) recorded at mid- and low-latitude observation sites near 120\textdegreeE in the China zone were used to investigate the response to a severe geomagnetic storm on March 17, 2015 (the minimum Dst -223 nT at 23 UT). The results showed that the strong geomagnetic storm caused a massive effect on the ionosphere. The characteristics of foF₂ and TEC did not show obvious perturbation during the main phase. Severe depletion of foF₂ and TEC was observed at all stations during the storm recovery period. The maximum absolute discrepancy in TEC compared with the past 27-day average value was 78 TECU, and the minimum percentage deviations reached -71\% at Fuzhou (26.1\textdegreeN,\ 119.3\textdegreeE). The minimum percentage deviations of decrease in foF₂ reached -65\% at Sanya (18.1\textdegreeN,\ 109.3\textdegreeE) and Mohe (53.5\textdegreeN,\ 122.3\textdegreeE). This was an infrequent negative effect that foF₂ and TEC sustained throughout the day with extremely low level on March 18. The O/N₂ rate showed a distinct reduction on March 18 in the China zone, which may be mainly responsible for the severe depletion of foF₂ and TEC. The spread-F seemed to be developed at first but was then suppressed to some extent during the main phase. During the recovery phase, the spread-F was suppressed at Sanya, while it developed at Wuhan and Mohe. The disturbance electric fields and thermospheric circulation may contribute to this phenomenon.

Liu, Guoqi; Shen, Hua;

Published by: Advances in Space Research Published on: 05/2017

YEAR: 2017 DOI: 10.1016/j.asr.2017.02.021

The effect of ring current electron scattering rates on magnetosphere-ionosphere coupling

This simulation study investigated the electrodynamic impact of varying descriptions of the diffuse aurora on the magnetosphere-ionosphere (M-I) system. Pitch angle diffusion caused by waves in the inner magnetosphere is the primary source term for the diffuse aurora, especially during storm time. The magnetic local time (MLT) and storm-dependent electrodynamic impacts of the diffuse aurora were analyzed using a comparison between a new self-consistent version of the Hot Electron Ion Drift Integrator with varying electron scattering rates and real geomagnetic storm events. The results were compared with Dst and hemispheric power indices, as well as auroral electron flux and cross-track plasma velocity observations. It was found that changing the maximum lifetime of electrons in the ring current by 2\textendash6\ h can alter electric fields in the nightside ionosphere by up to 26\%. The lifetime also strongly influenced the location of the aurora, but the model generally produced aurora equatorward of observations.

Perlongo, N.; Ridley, A.; Liemohn, M.; Katus, R.;

Published by: Journal of Geophysical Research: Space Physics Published on: 04/2017

YEAR: 2017 DOI: 10.1002/2016JA023679

Regional differences of the ionospheric response to the July 2012 geomagnetic storm

The July 2012 geomagnetic storm is an extreme space weather event in solar cycle 24, which is characterized by a southward interplanetary geomagnetic field lasting for about 30\ h below -10\ nT. In this work, multiple instrumental observations, including electron density from ionosondes, total electron content (TEC) from Global Positioning System, Jason-2, and Gravity Recovery and Climate Experiment, and the topside ion concentration observed by the Defense Meteorological Satellite Program spacecraft are used to comprehensively present the regional differences of the ionospheric response to this event. In the Asian-Australian sector, an intensive negative storm is detected near longitude ~120\textdegreeE on 16 July, and in the topside ionosphere the negative phase is mainly existed in the equatorial region. The topside and bottomside TEC contribute equally to the depletion in TEC, and the disturbed electric fields make a reasonable contribution. On 15 July, the positive storm effects are stronger in the Eastside than in the Westside. The topside TEC make a major contribution to the enhancement in TEC for the positive phases, showing the important role of the equatorward neutral winds. For the American sector, the equatorial ionization anomaly intensification is stronger in the Westside than in the Eastside and shows the strongest feature in the longitude ~110\textdegreeW. The combined effects of the disturbed electric fields, composition disturbances, and neutral winds cause the complex storm time features. Both the topside ion concentrations and TEC reveal the remarkable hemispheric asymmetry, which is mainly resulted from the asymmetry in neutral winds and composition disturbances.

Kuai, Jiawei; Liu, Libo; Lei, Jiuhou; Liu, Jing; Zhao, Biqiang; Chen, Yiding; Le, Huijun; Wang, Yungang; Hu, Lianhuan;

Published by: Journal of Geophysical Research: Space Physics Published on: 04/2017

YEAR: 2017 DOI: 10.1002/2016JA023844

Regional differences of the ionospheric response to the July 2012 geomagnetic storm

The July 2012 geomagnetic storm is an extreme space weather event in solar cycle 24, which is characterized by a southward interplanetary geomagnetic field lasting for about 30\ h below -10\ nT. In this work, multiple instrumental observations, including electron density from ionosondes, total electron content (TEC) from Global Positioning System, Jason-2, and Gravity Recovery and Climate Experiment, and the topside ion concentration observed by the Defense Meteorological Satellite Program spacecraft are used to comprehensively present the regional differences of the ionospheric response to this event. In the Asian-Australian sector, an intensive negative storm is detected near longitude ~120\textdegreeE on 16 July, and in the topside ionosphere the negative phase is mainly existed in the equatorial region. The topside and bottomside TEC contribute equally to the depletion in TEC, and the disturbed electric fields make a reasonable contribution. On 15 July, the positive storm effects are stronger in the Eastside than in the Westside. The topside TEC make a major contribution to the enhancement in TEC for the positive phases, showing the important role of the equatorward neutral winds. For the American sector, the equatorial ionization anomaly intensification is stronger in the Westside than in the Eastside and shows the strongest feature in the longitude ~110\textdegreeW. The combined effects of the disturbed electric fields, composition disturbances, and neutral winds cause the complex storm time features. Both the topside ion concentrations and TEC reveal the remarkable hemispheric asymmetry, which is mainly resulted from the asymmetry in neutral winds and composition disturbances.

Kuai, Jiawei; Liu, Libo; Lei, Jiuhou; Liu, Jing; Zhao, Biqiang; Chen, Yiding; Le, Huijun; Wang, Yungang; Hu, Lianhuan;

Published by: Journal of Geophysical Research: Space Physics Published on: 04/2017

YEAR: 2017 DOI: 10.1002/2016JA023844

The scintillation prediction observations research task (SPORT): an international science mission using a cubesat

UV Airglow images from TIMED GUVI clearly showing the equatorial anomaly with embedded depletions that have penetrated through the F peak. Green, Red and Blue traces show the

Spann, James; Swenson, Charles; Durao, Otavio; Loures, Luis; Heelis, Rod; Bishop, Rebecca; Le, Guan; Abdu, Mangalathayil; Krause, Linda; Fry, Craig; , others;

Published by: Published on:

YEAR: 2017 DOI:

Model simulations of ion and electron density profiles in ionospheric E and F regions

We develop a time‐dependent theoretical numerical model to simulate the density profiles of the ions (ie, O + ( 2 P), O + ( 2 D), N 2 + , O + ( 4 S), N + , O 2 + , and NO + ) and free

Lin, YC; Chu, YH;

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

YEAR: 2017 DOI: 10.1002/2016JA022855

Predictable and unpredictable ionospheric disturbances during St. Patrick s Day magnetic storms of 2013 and 2015 and on 8—9 March 2008

We present a comparative analysis of first principles Global Self‐consistent Model of the Thermosphere, Ionosphere, and Protonosphere (GSM TIP) in prediction of ionospheric

Dmitriev, AV; Suvorova, AV; Klimenko, MV; Klimenko, VV; Ratovsky, KG; Rakhmatulin, RA; Parkhomov, VA;

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

YEAR: 2017 DOI: 10.1002/2016JA023260

Predictable and unpredictable ionospheric disturbances during St. Patrick s Day magnetic storms of 2013 and 2015 and on 8—9 March 2008

We present a comparative analysis of first principles Global Self‐consistent Model of the Thermosphere, Ionosphere, and Protonosphere (GSM TIP) in prediction of ionospheric

Dmitriev, AV; Suvorova, AV; Klimenko, MV; Klimenko, VV; Ratovsky, KG; Rakhmatulin, RA; Parkhomov, VA;

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

YEAR: 2017 DOI: 10.1002/2016JA023260

Predictable and unpredictable ionospheric disturbances during St. Patrick s Day magnetic storms of 2013 and 2015 and on 8—9 March 2008

We present a comparative analysis of first principles Global Self‐consistent Model of the Thermosphere, Ionosphere, and Protonosphere (GSM TIP) in prediction of ionospheric

Dmitriev, AV; Suvorova, AV; Klimenko, MV; Klimenko, VV; Ratovsky, KG; Rakhmatulin, RA; Parkhomov, VA;

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

YEAR: 2017 DOI: 10.1002/2016JA023260

Data-Driven Inference and Investigation of Thermosphere Dynamics and Variations

Mehta, Piyush; Linares, Richard; Sutton, Eric;

Published by: order Published on:

YEAR: 2017 DOI:

PCA and vTEC climatology at midnight over mid-latitude regions

The effect of the thermospheric vertical neutral wind on vertical total electron content (vTEC) variations including longitudinal anomaly, remaining winter anomaly, mid-latitude summer

Natali, Maria; Meza, A;

Published by: Earth, Planets and Space Published on:

YEAR: 2017 DOI: 10.1186/s40623-017-0757-5

Equatorial ionospheric disturbances over the East African sector during the 2015 St. Patrick’s day storm

Olwendo, OJ; Cesaroni, Claudio; Yamazaki, Yosuke; Cilliers, P;

Published by: Advances in Space Research Published on:

YEAR: 2017 DOI:

The causes of thermospheric composition variations during and after major geomagnetic storms

Wang, Wenbin; Burns, Alan; Zhang, Yongliang; Liu, Jing;

Published by: Published on:

YEAR: 2017 DOI:

The scintillation prediction observations research task (sport) mission