Article
Environmental Sciences
Rasim Shahzad, Munawar Shah, M. Arslan Tariq, Andres Calabia, Angela Melgarejo-Morales, Punyawi Jamjareegulgarn, Libo Liu
Summary: In this study, we analyzed the variations in vertical total electron content (vTEC) from the Global Navigation Satellite System (GNSS) during geomagnetic storms in different continents and latitudes. The ionospheric disturbances at low and mid-latitudes were investigated in terms of prompt penetration electric field (PPEF), equatorial electrojet (EEJ), and magnetic H component. Positive vTEC disturbances were observed in East and Southeast Asia, Russia, and Oceania, while negative vTEC disturbances were observed in South America. Similar results were also found in vTEC data retrieved from Swarm satellites. The ionospheric plasma tended to rapidly increase during the afternoon and exhibit opposite behavior at nighttime. The expansion of the equatorial ionization anomaly (EIA) crest to higher latitudes was driven by PPEF during the main and recovery phases of the storms. The magnetic H component showed longitudinal behavior along with EEJ enhancement near the magnetic equator.
Article
Geosciences, Multidisciplinary
Thomas J. Immel, Brian J. Harding, Roderick A. Heelis, Astrid Maute, Jeffrey M. Forbes, Scott L. England, Stephen B. Mende, Christoph R. Englert, Russell A. Stoneback, Kenneth Marr, John M. Harlander, Jonathan J. Makela
Summary: Observations from the National Aeronautics and Space Administration Ionospheric Connection Explorer have confirmed the link between thermospheric winds and ionospheric plasma variability, presenting challenges in predicting changes in Earth's equatorial ionosphere for geopositioning systems and radio communications. Improved prediction of Earth's plasma environment is expected through prediction of thermospheric winds.
Article
Astronomy & Astrophysics
Ningchao Wang, Tong Dang, Jiuhou Lei, Wenbin Wang, Seebany Datta-Barua
Summary: This study used the Thermosphere-Ionosphere-Electrodynamics General Circulation Model to model the IT system and found that during a geomagnetic storm, LCSs in the thermosphere and ionosphere shift equatorward, align more closely, and maintain a dawn-dusk asymmetry. The collocation of thermospheric LCSs and ionospheric LCSs during the storm suggests simultaneous energy input into the thermosphere and ionosphere, with ion drag being the dominant effect causing LCS alignment.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2021)
Article
Engineering, Aerospace
Dibyendu Sur, Sarbani Ray, Ashik Paul
Summary: This paper observes the super-imposed effects of intense and moderate solar flares, Coronal Mass Ejection (CME), and High-Speed Solar Wind (HSSW) driven geomagnetic storm events on the ionosphere and thermosphere at mid and high latitudes during low solar activity periods. The study finds that the effects were the highest during May 27-31, 2017 among all the observed events.
ADVANCES IN SPACE RESEARCH
(2022)
Article
Geosciences, Multidisciplinary
Hui Wang, H. Luehr, K. D. Zhang
Summary: This study investigates the longitudinal and seasonal variations of thermospheric superrotation at the magnetic equator, revealing different patterns during equinoxes and solstices. The interaction between the neutral wind and geomagnetic field plays a crucial role in superrotation, rather than F-region electron density. Lower atmospheric tides tend to suppress superrotation but contribute to longitudinal patterns.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Engineering, Electrical & Electronic
Munawar Shah, Ayesha Abbas, Muhsan Ehsan, Andres Calabia, Binod Adhikari, M. Tariq, Junaid Ahmed, Jose Francisco de Oliveira-Junior, Jianguo Yan, Angela Melgarejo-Morales, Punyawi Jamjareegulgarn
Summary: This study investigates the ionospheric storm time responses during August 2018 in the South American region using various observables. The results show that strong ionospheric and upper-atmospheric disturbances have a lasting impact on ionospheric variables during the storm recovery phase and following period. The variations in VTEC are significant during the daytime, with low values observed during the nighttime in the main phase and high values in the recovery phase. The equatorial ionization anomaly expands due to prompt penetration electric field.
IEEE JOURNAL OF SELECTED TOPICS IN APPLIED EARTH OBSERVATIONS AND REMOTE SENSING
(2022)
Article
Astronomy & Astrophysics
Shuang Xu, Sharon L. Vadas, Jia Yue
Summary: This study analyzed thermospheric density data to study high latitude traveling atmospheric disturbances (TADs) in austral winter. The distribution of TADs during geomagnetic quiet time depended on spatial scale and altitude, with different lambda track values showing varying patterns at different altitudes. Additionally, TAD morphology for higher geomagnetic activity levels showed greatly enhanced amplitudes.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Ruoxi Li, Jiuhou Lei
Summary: This study utilized satellite POD data to investigate the thermospheric variations in response to geomagnetic storms, showing hemispheric asymmetries and day-night variations in thermospheric mass densities at different altitudes and local times. The results demonstrated the potential of using satellite POD data to study upper atmospheric variations.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2021)
Article
Environmental Sciences
Bingkun Yu, Xianghui Xue, Christopher J. Scott, Jianfei Wu, Xinan Yue, Wuhu Feng, Yutian Chi, Daniel R. Marsh, Hanli Liu, Xiankang Dou, John M. C. Plane
Summary: This study investigates ionospheric irregularities using scintillation data from COSMIC satellites and simulations from the Whole Atmosphere Community Climate Model, combined with the chemistry of metals and ground-based observations. The results show that the lower thermospheric meridional circulation influences the transport of metallic ions within sporadic E layers, with implications for large-scale interhemispheric transport in the thermosphere-ionosphere system.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2021)
Article
Geosciences, Multidisciplinary
Kristina Collins, John Gibbons, Nathaniel Frissell, Aidan Montare, David Kazdan, Darren Kalmbach, David Swartz, Robert Benedict, Veronica Romanek, Rachel Boedicker, William Liles, William Engelke, David G. McGaw, James Farmer, Gary Mikitin, Joseph Hobart, George Kavanagh, Shibaji Chakraborty
Summary: This study measures the measurable effects of ionospheric variability on the Doppler shift of HF skywave signals using low-cost equipment. It presents a modular network called PSWS that measures Doppler shift in carrier signals and serves as a building block for a large-scale ionospheric and HF propagation measurement network. The study also provides software tools for data visualization and analysis and demonstrates the use of the data in event-based analyses and accuracy assessment of ionospheric models.
EARTH SYSTEM SCIENCE DATA
(2023)
Article
Biochemistry & Molecular Biology
Aleksandra A. Ageeva, Alexander Kruppa, Ilya M. Magin, Simon Babenko, Tatyana Leshina, Nikolay E. Polyakov
Summary: Electron transfer plays a crucial role in ROS generation, and glycyrrhizin acts as an exogenous antioxidant by inhibiting ROS generation and trapping free radicals.
Article
Astronomy & Astrophysics
N. Nowrouzi, L. M. Kistler, K. Zhao, E. J. Lund, C. Mouikis, G. Payne, B. Klecker
Summary: This study investigates the variations of ionospheric O+ and H+ outflow during SIR and CME storms and their dependence on storm phase, storm size, solar EUV flux, solar cycle, and seasonal effects. The results show that both CME and SIR storms exhibit peak O+ and H+ fluences during the main phase, with a decline in the recovery phase. However, CME storms also show a significant increase during the initial phase, which can be attributed to the onset of outflow before the main phase. The study also finds that outflow fluence is higher for intense storms and during solar maximum.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2023)
Article
Engineering, Aerospace
M. Arslan Tariq, Yuyan Yang, Munawar Shah, M. Ali Shah, Talat Iqbal, Libo Liu
Summary: This paper presents the longitudinal dependence of ionospheric responses during intense geomagnetic storms in May and September 2017. The study found that the storms triggered ionospheric enhancements or negative phase, which were influenced by the interplanetary magnetic field and prompt penetration electric field.
ADVANCES IN SPACE RESEARCH
(2022)
Article
Geochemistry & Geophysics
Nao Yoshida, Naoki Terada, Hiromu Nakagawa, David A. Brain, Shotaro Sakai, Yuki Nakamura, Mehdi Benna, Kei Masunaga
Summary: This study reports seasonal and dust-related variations in neutral and ion species in the dayside Martian upper atmosphere, as well as analyzes the observed patterns using a photochemical equilibrium model. The research demonstrates the impact of seasonality and regional dust storms on ion and neutral species in the Martian atmosphere.
JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS
(2021)
Article
Astronomy & Astrophysics
Yongliang Zhang, Larry J. Paxton, Robert Schaefer
Summary: The developed method effectively separates the ionospheric and thermospheric contributions in the observed 135.6 nm radiance, improving the estimation of the thermospheric O/N-2 ratio and providing the ionospheric signature in the radiance data. The comparison between different ionospheric radiances and GPS TEC data confirms the reliability of the method, which can be applied to other far ultraviolet data for similar measurements.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2021)
Article
Geosciences, Multidisciplinary
Yihui Cai, Xinan Yue, Wenbin Wang, Shun-Rong Zhang, Huixin Liu, Jiuhou Lei, Zhipeng Ren, Yiding Chen, Feng Ding, Dexin Ren
Summary: The electron density of the ionospheric F-region is anomalously higher in the evening than during the daytime in geomagnetic mid-latitude regions in the summer. The formation of this unexpected diurnal variation is influenced by meridional winds, topside influx from sunset ionospheric collapse, and other factors. However, the role of these factors and their interactions remain controversial. In this study, a numerical model driven by statistical topside O+ diffusive flux data is used to provide new insights into the formation of the evening density peak, emphasizing the critical importance of the topside diffusive flux.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Astronomy & Astrophysics
K. H. Pham, B. Zhang, K. Sorathia, T. Dang, W. Wang, V. Merkin, H. Liu, D. Lin, M. Wiltberger, J. Lei, S. Bao, J. Garretson, F. Toffoletto, A. Michael, J. Lyon
Summary: This study investigates the global distribution of thermospheric density perturbations during geomagnetic storms by combining satellite observations and simulation models. The results show that these perturbations occur not only in high latitude regions, but also in the equatorial region. The simulation results demonstrate that traveling atmospheric disturbances generated at high latitudes result in larger density peaks in the equatorial region. This study highlights the importance of studying thermospheric density variations globally.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2022)
Editorial Material
Astronomy & Astrophysics
Mike Hapgood, Huixin Liu, Noe Lugaz
Summary: The launch of Starlink satellites by SpaceX on 3 February 2022 resulted in a significant loss due to enhanced atmospheric drag caused by a minor geomagnetic storm. This incident highlights the practical and financial consequences even modest space weather can have. SpaceX responded agilely by adjusting the subsequent launch to mitigate future space weather losses. The article discusses the lessons to be learned by the space industry and the space weather community.
SPACE WEATHER-THE INTERNATIONAL JOURNAL OF RESEARCH AND APPLICATIONS
(2022)
Article
Geosciences, Multidisciplinary
Weizheng Fu, Tatsuhiro Yokoyama, Nicholas Ssessanga, Mamoru Yamamoto, Peng Liu
Summary: This paper investigates the phenomenon of ionospheric irregularities in the night-time mid-latitude region through observations and theoretical analysis, and supports the hypothesis of frequent coupling between the E and F regions. The study utilizes total electron content measurements to analyze small-scale perturbations in ionospheric electron density. The results demonstrate the coexistence of irregular structures aligned in the northwest-southeast direction in both the E and F regions, providing clear evidence of strong coupling between E- and F-region irregularities.
EARTH PLANETS AND SPACE
(2022)
Editorial Material
Astronomy & Astrophysics
Noe Lugaz, Jennifer L. Gannon, Shasha Zou, Steven K. Morley, Huixin Liu, Brett A. Carter, Michael Hapgood
Summary: The next decade's plan for space and solar physics is about to commence, with white papers due in the second half of 2022 and committees and panels working throughout 2023. Space weather science and operations will play a crucial role in this plan. The community is thus invited to prepare white papers and contribute to the advancement of space weather research and capabilities in the coming decades. A summary of recommendations related to space weather from the last two decade surveys is also provided.
SPACE WEATHER-THE INTERNATIONAL JOURNAL OF RESEARCH AND APPLICATIONS
(2022)
Article
Astronomy & Astrophysics
Peng Liu, Tatsuhiro Yokoyama, Weizheng Fu, Mamoru Yamamoto
Summary: This study develops a real-time processing algorithm for detecting medium-scale traveling ionospheric disturbances (MSTIDs) using deep learning. The algorithm can intelligently discriminate MSTIDs and obtain statistical characteristics. The research results are significant for understanding the relationship between MSTID characteristics and solar/geomagnetic activity.
SPACE WEATHER-THE INTERNATIONAL JOURNAL OF RESEARCH AND APPLICATIONS
(2022)
Article
Geosciences, Multidisciplinary
Tatsuhiro Yokoyama, Rieko Takagi, Mamoru Yamamoto
Summary: This study investigates the occurrence characteristics of 150-km echoes in low-latitude regions using the Equatorial Atmosphere Radar (EAR) in Indonesia. The long-term observations show that the occurrence rate of 150-km echoes exhibits a semiannual variation, with two peaks during solstices, and is negatively correlated with EUV flux and Sigma Kp. However, regardless of the geomagnetic activity, the occurrence rate is always low during the high solar activity period. Additionally, this study reports a negative correlation between geomagnetic activity and the occurrence of 150-km echoes for the first time.
EARTH PLANETS AND SPACE
(2022)
Article
Astronomy & Astrophysics
Yihui Cai, Xinan Yue, Wenbin Wang, Shun-Rong Zhang, Huixin Liu, Dong Lin, Haonan Wu, Jia Yue, Sean L. Bruinsma, Feng Ding, Zhipeng Ren, Libo Liu
Summary: The upper boundary height of the traditional community general circulation model has been extended to improve the study of the topside ionosphere/thermosphere. The extended model, TIEGCM-X, shows good agreement with observations and has potential applications in ionospheric/thermospheric studies.
SPACE WEATHER-THE INTERNATIONAL JOURNAL OF RESEARCH AND APPLICATIONS
(2022)
Article
Astronomy & Astrophysics
Qiong Tang, Chen Zhou, Huixin Liu, Zhitao Du, Yi Liu, Jiaqi Zhao, Zhibin Yu, Zhengyu Zhao, Xueshang Feng
Summary: The research utilizes the measurements from the Constellation Observing System for Meteorology, Ionosphere, and Climate radio occultation S4 indices to investigate the global structure and seasonal variations of tidal components in the sporadic-E (Es) layer. The findings reveal a wave-4 longitudinal structure in the diurnal tidal amplitude, indicating a diurnal tidal component influence. The study also identifies differences in the diurnal tidal pattern between the lower altitude Es layer and the higher altitude Es layer, suggesting that the wind shear theory may not be applicable for Es layer formation at low altitudes.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2022)
Article
Astronomy & Astrophysics
F. Guenzkofer, D. Pokhotelov, G. Stober, H. Liu, H-L Liu, N. J. Mitchell, A. Tjulin, C. Borries
Summary: This study investigates the presence of strong semidiurnal oscillations in the high-latitude thermosphere using measurements from incoherent scatter radar and global circulation models. The results reveal different forcing mechanisms for the upper and lower bands of tidal oscillations, and indicate that the transition of tides in the altitude region between 90 and 150 km is more complex than previously described.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Masaru Kogure, Huixin Liu, Chihiro Tao
Summary: This study investigates the mechanisms for the response of the thermospheric zonal mean winds to doubled CO2 concentration. The results show that ion drag, molecular viscosity, and meridional pressure gradient force are the dominant forces affected by doubled CO2 concentration. These forces attenuate each other, leading to a strengthening of the southward wind in the northern hemisphere and latitudes north of 35 degrees S. The increased ion density in the northern hemisphere is identified as the underlying trigger for the wind response to increasing CO2 concentration.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2022)
Editorial Material
Astronomy & Astrophysics
S. K. Morley, H. Liu, B. A. Carter, J. L. Gannon, N. Lugaz
Summary: This editorial aims to raise awareness of the best practices in open research and promote practical discussions on the implementation of AGU's data and software policy in space weather research. It also encourages authors to take additional steps to ensure clear credit to all contributors.
SPACE WEATHER-THE INTERNATIONAL JOURNAL OF RESEARCH AND APPLICATIONS
(2022)
Article
Astronomy & Astrophysics
Qiong Tang, Chen Zhou, Huixin Liu, Yi Liu, Jiaqi Zhao, Zhibin Yu, Lianhuan Hu, Zhengyu Zhao, Xueshang Feng
Summary: This paper investigates the vertical motion of Earth's sporadic-E (Es) layer through the use of image processing techniques. The study analyzes ionograms from multiple locations and compares them with wind measurements to understand the role of tides in the formation and descent of the Es layer. The results show that while high-altitude Es layers descend rapidly with wind shear nulls, lower-lying Es layers stay at the bottom of the E region for extended periods, indicating a different mechanism at play.
SPACE WEATHER-THE INTERNATIONAL JOURNAL OF RESEARCH AND APPLICATIONS
(2023)
Editorial Material
Astronomy & Astrophysics
J. L. Gannon, S. Morley, N. Lugaz, H. Liu, B. Carter, S. Zou
Summary: Recently, there has been a movement in the space weather community to support ground-based sensor networks. Despite the widespread use of ground-based sensors in various aspects of space weather, they do not have a clear home within any United States agency or department for long-term support. As a result, there has been an ongoing struggle to maintain important space weather sensors and networks.
SPACE WEATHER-THE INTERNATIONAL JOURNAL OF RESEARCH AND APPLICATIONS
(2023)
Article
Astronomy & Astrophysics
Weizheng Fu, Tatsuhiro Yokoyama, Nicholas Ssessanga, Guanyi Ma, Mamoru Yamamoto
Summary: This paper studies the conjugate MSTIDs in mid-latitude nighttime ionospheres to understand the effects of E-F coupling in the interhemispheric coupled ionosphere. Observations and analysis of the hemisphere-coupled ionospheres over Japan and Australia are conducted using TEC measurements and multi-source observations. A double-thin-shell model is introduced to analyze the ionospheric responses in E and F regions. The results provide evidence that the Es layers in the summer hemisphere drive F-region geomagnetic conjugate irregularities and trigger local E-F coupling and inter-hemispheric coupling.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2023)
