Article
Astronomy & Astrophysics
Beena Bhatt, Harish Chandra
Summary: We examined the Forbush decreases (FDs) associated with solar flares and coronal mass ejections (CMEs) from January 2008 to December 2019, comparing them to the findings of a previous study. Through statistical analysis, we found that the northern 11-20 degrees latitude band had the highest number of FD-associated flare events. Further analysis was conducted on the two most significant events.
Article
Engineering, Aerospace
Anastasiya Zhukova, Dmitry Sokoloff, Valentina Abramenko, Anna Khlystova
Summary: Based on the study of solar active regions, two categories of active regions were identified: A-type (regular bipolar) and B-type (irregular). Statistical analysis showed that the numbers of both types of active regions are correlated with the solar activity cycle and exhibit significant north-south asymmetry.
ADVANCES IN SPACE RESEARCH
(2023)
Article
Environmental Sciences
Oswald Didier Franck Grodji, Vafi Doumbia, Paul Obiakara Amaechi, Christine Amory-Mazaudier, Kouassi N'guessan, Kassamba Abdel Aziz Diaby, Tuo Zie, Kouadio Boka
Summary: In this study, the impact of solar flares on the geomagnetic field was investigated using magnetometer measurements. The results showed that solar flares have a significant effect on the geomagnetic field components, with a peak amplitude occurring a few minutes after the flare. The patterns and intensities of the effects varied for different field components and were influenced by various factors. The monthly variations of the effects were similar for the two cycles, but the impact was stronger in cycle 23.
Article
Chemistry, Physical
N. M. Wateed, H. A. Motaweh, M. Y. Hanfi, M. Sayyed, M. U. Khandaker, A. A. Darwish, A. Sh. M. Elshoukrofy
Summary: The study of solar wind is important due to its key role in space weather. Solar wind is composed of plasma streams with varying hydrodynamic and magnetic properties, and it can be categorized into slow, rapid, and disturbed streams. By analyzing data on solar wind speed and cosmic ray intensity, it was found that low-speed solar wind events occur more frequently.
RADIATION PHYSICS AND CHEMISTRY
(2022)
Article
Engineering, Aerospace
Rajkumar Hajra, Ezequiel Echer, Adriane Marques de Souza Franco, Mauricio Jose Alves Bolzan
Summary: Super substorm (SSS) events are characterized by intense westward auroral electrojet currents and are caused by solar wind-magnetosphere coupling. This study presents the first analysis of the variability in Earth's magnetotail and its coupling to the solar wind, geosynchronous orbit, and auroral ionosphere during SSS events. The results show that SSS events are associated with turbulent plasma sheets in the magnetotail and the injection of energetic electrons and protons. The injection of energetic protons leads to the scattering of MeV electrons and their loss to the atmosphere during SSS events.
ADVANCES IN SPACE RESEARCH
(2023)
Article
Astronomy & Astrophysics
Beatriz Sanchez-Cano, Mark Lester, Marco Cartacci, Roberto Orosei, Olivier Witasse, Pierre-Louis Blelly, Wlodek Kofman
Summary: This study investigates the behavior of Mars' ionosphere during two consecutive solar minima (23/24 and 24/25) using the same dataset. The Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) is used to study the total electron content and the variability of the electron density profiles. The study confirms that the empirical model equations for the Martian ionosphere derived for the solar minimum 23/24 are also valid and accurate for the solar minimum 24/25.
Article
Engineering, Aerospace
Angkita Hazarika, Kalyan Bhuyan, Bitap R. Kalita, Pradip K. Bhuyan, Arup Borgohain, Ramesh C. Tiwari
Summary: We compared the performance of three ionospheric models (IRI 2016, IRI-Plas 2017, and SAMI2) with total electron content (TEC) data obtained from Global Navigation Satellite Systems receivers. The results show that all the models overestimate the observed TEC, with IRI Plas showing the highest overestimation. IRI 2016 performed better than IRI Plas, and assimilating TEC data into IRI-Plas improved its performance.
ADVANCES IN SPACE RESEARCH
(2023)
Article
Physics, Multidisciplinary
Ezequiel Echer, Aline de Lucas, Rajkumar Hajra, Adriane Marques de Souza Franco, Mauricio J. A. Bolzan, Luis Eduardo Sales do Nascimento
Summary: Interplanetary shocks play an important role in the occurrence of ICMEs and CIRs. This study analyzed 297 fast forward shocks observed by the ACE spacecraft and found a higher occurrence rate during solar cycle 23 compared to cycle 24. The shocks had little correlation with geomagnetic activity.
BRAZILIAN JOURNAL OF PHYSICS
(2023)
Article
Astronomy & Astrophysics
V Manu, N. Balan, Q. H. Zhang, Z-Y Xing
Summary: The intensity and impulsive strength of geomagnetic activities in solar cycles 23-24 were investigated for the first time, revealing that the total intensity and impulsive strength in SC24 reduced by similar amounts in all latitudes, while the average intensity and impulsive strength decreased significantly in low latitudes.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Alexander A. Khokhlachev, Yuri Yermolaev, Irina G. Lodkina, Maria O. Riazantseva, Liudmila S. Rakhmanova
Summary: The study revealed that the decrease in solar activity in solar cycles affected the behavior of relative helium ions abundance inside interplanetary coronal mass ejections. The helium abundance significantly decreased in the low solar activity period, and the dependence on certain parameters became weaker during this period compared to high solar activity periods. Additionally, a dependence on the distance from spacecraft to the ICME axis was observed, with the maximum helium abundance measured at the minimum distance confirming the hypothesis of an helium-enriched electric current inside an ICME.
Article
Astronomy & Astrophysics
N. Gopalswamy, S. Yashiro, S. Akiyama, H. Xie, P. Makela, M-C Fok, C. P. Ferradas
Summary: This article reports on the solar and interplanetary causes of the third largest geomagnetic storm in solar cycle 24, which occurred on August 26, 2018. The study reveals that the prolonged acceleration of the coronal mass ejection, complex rotation of the magnetic flux rope, and high density in the interplanetary cloud are important factors contributing to the high intensity of the storm.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2022)
Article
Astronomy & Astrophysics
V. Manu, N. Balan, Qing-He Zhang, Zan-Yang Xing
Summary: Solar cycle 24 (2010-2019) was the weakest in 100 years, with activity 1/3 less than solar cycle 23 (1996-2009). The main factors determining the intensity of geomagnetic storms were found to be the solar wind velocity, the north-south component of the interplanetary magnetic field, and their product. Compared to solar cycle 23, the intensity of geomagnetic storms in solar cycle 24 decreased by 52%, 12%, and 45% at low, mid, and high latitudes, respectively.
SPACE WEATHER-THE INTERNATIONAL JOURNAL OF RESEARCH AND APPLICATIONS
(2023)
Article
Engineering, Aerospace
Muhammad Ayyaz Ameen, Haqqa Khursheed, Mehak Abdul Jabbar, Muneeza Salman Ali, Ghulam Murtaza, Muhammad Atiq, Zahra Bouya, Xiao Yu
Summary: This study investigates the variations in ionospheric parameters B0 and B1 at Multan during the solar minimum between cycles 23/24. The results show diurnal and seasonal patterns, with ABT-2009 model performing better in estimating B0 and B1 compared to other options. The study provides insights into the behavior of ionospheric profiles over Multan and may contribute to improving the sub-model ABT-2009 of IRI.
ADVANCES IN SPACE RESEARCH
(2021)
Article
Engineering, Aerospace
Juan Manuel Castano, Maria Paula Natali, Amalia Meza
Summary: In this study, the behavior of the mid-latitude ionospheric trough (MIT) during solar cycle 24 was analyzed using Global Ionospheric Maps (GIMs). The MIT position shows asymmetry between the Northern and Southern Hemispheres, with equatorward movement during high solar activity. In addition, there is a clear dependence between MIT position and solar wind speed and IMF Bz-component at certain time scales.
ADVANCES IN SPACE RESEARCH
(2021)
Article
Astronomy & Astrophysics
N. A. Tsyganenko, V. A. Andreeva, M. Sitnov, G. K. Stephens, J. W. Gjerloev, X. Chu, O. A. Troshichev
Summary: The evolution of the low-latitude magnetosphere over the substorm cycle was reconstructed using a high-resolution 3D representation of the magnetic field and data mining. The study quantified the magnetospheric state using four indices and showed that the intensification and collapse of the inner tail current during specific substorm events led to large-scale dipolarization of the field. The system then recovered and returned to its pre-substorm state.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2021)
Editorial Material
Astronomy & Astrophysics
Jeffrey J. Love, Carol A. Finn
SPACE WEATHER-THE INTERNATIONAL JOURNAL OF RESEARCH AND APPLICATIONS
(2017)
Article
Geosciences, Multidisciplinary
Jeffrey J. Love, Greg M. Lucas, Anna Kelbert, Paul A. Bedrosian
GEOPHYSICAL RESEARCH LETTERS
(2018)
Article
Astronomy & Astrophysics
Greg M. Lucas, Jeffrey J. Love, Anna Kelbert
SPACE WEATHER-THE INTERNATIONAL JOURNAL OF RESEARCH AND APPLICATIONS
(2018)
Article
Astronomy & Astrophysics
Jeffrey J. Love, Greg M. Lucas, Anna Kelbert, Paul A. Bedrosian
SPACE WEATHER-THE INTERNATIONAL JOURNAL OF RESEARCH AND APPLICATIONS
(2018)
Article
Astronomy & Astrophysics
Jeffrey J. Love
SPACE WEATHER-THE INTERNATIONAL JOURNAL OF RESEARCH AND APPLICATIONS
(2018)
Article
Astronomy & Astrophysics
Jeffrey J. Love, Greg M. Lucas, Paul A. Bedrosian, Anna Kelbert
SPACE WEATHER-THE INTERNATIONAL JOURNAL OF RESEARCH AND APPLICATIONS
(2019)
Article
Astronomy & Astrophysics
Jeffrey J. Love, Hisashi Hayakawa, Edward W. Cliver
SPACE WEATHER-THE INTERNATIONAL JOURNAL OF RESEARCH AND APPLICATIONS
(2019)
Article
Astronomy & Astrophysics
Jeffrey J. Love, Hisashi Hayakawa, Edward W. Cliver
SPACE WEATHER-THE INTERNATIONAL JOURNAL OF RESEARCH AND APPLICATIONS
(2019)
Article
Astronomy & Astrophysics
Daniel T. Welling, Jeffrey J. Love, E. Joshua Rigler, Denny M. Oliveira, Colin M. Komar, Steven K. Morley
Summary: In this study, estimates for an interplanetary coronal mass ejection were used to drive a model of geospace and the results showed similar responses to previous studies but with deviations at the equator. The physics-based simulation yielded more accurate estimates of the geospace response to such an event.
SPACE WEATHER-THE INTERNATIONAL JOURNAL OF RESEARCH AND APPLICATIONS
(2021)
Article
Astronomy & Astrophysics
Jeffrey J. Love
Summary: This study compiled and fitted the maximum magnetic storm intensities from solar cycles 14-24, estimating storm intensity and the probability of future storms exceeding certain thresholds.
SPACE WEATHER-THE INTERNATIONAL JOURNAL OF RESEARCH AND APPLICATIONS
(2021)
Article
Astronomy & Astrophysics
Benjamin S. Murphy, Greg M. Lucas, Jeffrey J. Love, Anna Kelbert, Paul A. Bedrosian, E. Joshua Rigler
Summary: This study evaluates the impact of MT data sampling density on geoelectric hazard assessments, finding that higher density MT data can lead to significant differences in line-averaged electric field estimates and subregional hazard patterns. These differences reflect short-spatial-scale variability in Earth conductivity, related to regional lithotectonic structure and history.
SPACE WEATHER-THE INTERNATIONAL JOURNAL OF RESEARCH AND APPLICATIONS
(2021)
Article
Astronomy & Astrophysics
Jeffrey J. Love, Greg M. Lucas, Benjamin S. Murphy, Paul A. Bedrosian, E. Joshua Rigler, Anna Kelbert
Summary: This study analyzes Earth-surface geoelectric fields and induced voltages on electricity transmission power-grids caused by a late-phase E3 nuclear electromagnetic pulse (EMP). It concludes that simple impedance models do not accurately estimate the geoelectric hazard in complex geological settings.
EARTH AND SPACE SCIENCE
(2021)
Article
Astronomy & Astrophysics
Jeffrey J. Love, Greg M. Lucas, E. Joshua Rigler, Benjamin S. Murphy, Anna Kelbert, Paul A. Bedrosian
Summary: This study examines the relationship between geomagnetic and geoelectric field variation, Earth-surface impedance, and operational interference on electric-power systems during a magnetic storm in 1989. The results show that anomalies were concentrated in areas with high geoelectric field amplitudes and a resistive lithosphere. Furthermore, the study suggests that future research should focus on denser geomagnetic monitoring, additional magnetotelluric surveying, and access to power-system impact data.
SPACE WEATHER-THE INTERNATIONAL JOURNAL OF RESEARCH AND APPLICATIONS
(2022)
Article
Astronomy & Astrophysics
Michael D. D. Hartinger, Xueling Shi, Craig J. J. Rodger, Ikuko Fujii, E. Joshua Rigler, Karl Kappler, Jurgen Matzka, Jeffrey J. J. Love, Joseph B. H. Baker, Daniel H. H. Mac Manus, Michael Dalzell, Tanja Petersen
Summary: Previous studies have shown that large-amplitude geomagnetically induced current (GIC) related to magnetospheric Ultra Low Frequency (ULF) waves are more common at latitudes above 60 degrees and with periods longer than 120 seconds. Conversely, GIC amplitudes are smaller at lower latitudes and with shorter wave periods, and there are fewer reports of waves associated with GIC at lower latitudes. This study aims to investigate whether these trends are due to the undersampling of ULF waves in commonly available measurements with 60-second sampling intervals. Data from the 29-31 October 2003 geomagnetic storm, with sampling intervals of 0.5-10 seconds, is used to examine waves with periods...
SPACE WEATHER-THE INTERNATIONAL JOURNAL OF RESEARCH AND APPLICATIONS
(2023)
Article
Astronomy & Astrophysics
Jeffrey J. Love, E. Joshua Rigler, Michael D. Hartinger, Greg M. Lucas, Anna Kelbert, Paul A. Bedrosian
Summary: This study analyzes geophysical records and reports of interference on long-line communication and power systems during the magnetic storm on March 24, 1940. The interference mainly occurred during daytime, after storm sudden commencements and during the storm's main phase. The storm-induced unusually large-amplitude and rapid geomagnetic field variation, possibly driven by interplanetary coronal-mass ejections. The research concludes that the March 1940 magnetic storm was highly effective at inducing geoelectric fields, which could potentially interfere with modern electric-power-transmission systems.
SPACE WEATHER-THE INTERNATIONAL JOURNAL OF RESEARCH AND APPLICATIONS
(2023)