Article
Astronomy & Astrophysics
Golekamang P. Thaganyana, John Bosco Habarulema, Chigomezyo Ngwira, Irfan Azeem
Summary: This article presents observations of medium to large-scale traveling ionospheric disturbances (TIDs) originating from high latitudes, and propagating across the equator into the opposite hemisphere in the African-European sector during geomagnetically quiet conditions between 2010 and 2018. The study identifies the characteristics of the TIDs, including their propagation velocities, periods, and wavelengths, and suggests that tertiary gravity waves from orographic forcing may be the likely source of the observed TIDs.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Larry R. Lyons, Yukitoshi Nishimura, Shunrong Zhang, Anthea Coster, Jiang Liu, William A. Bristow, Ashton S. Reimer, Roger H. Varney, Don L. Hampton
Summary: The study investigates the direct connection of large-scale traveling ionospheric disturbances (LSTIDs) to auroral streamers and flow channels using simultaneous auroral imaging, radar flows, and total electron content (TEC) measurements. The results suggest that the TIDs are likely LSTIDs, but more data is needed to confirm their large scale nature. Additionally, the study shows evidence that TIDs are connected to groups of auroral streamers and flow channels, rather than individual streamers.
FRONTIERS IN ASTRONOMY AND SPACE SCIENCES
(2021)
Article
Environmental Sciences
Zhuo Chen, Yang Liu, Kai Guo, Jinling Wang
Summary: This study investigates the effects of ionospheric irregularities on Global Navigation Satellite System (GNSS) and low earth orbit (LEO) satellite propagation using COSMIC data. The alpha-mu model exhibits the best performance in all considered scintillation intensities.
Article
Geochemistry & Geophysics
Ting Li, Yongxin Gao, Chieh-Hung Chen, Xuemin Zhang, Yang-Yi Sun
Summary: On January 15, 2022, a powerful eruption of the Hunga Tonga-Hunga Ha'apai submarine volcano occurred near the Ha'apai Islands in Tonga, generating atmospheric waves that spread globally. The study focuses on the variation of total electron content (TEC) in China using the BeiDou Navigation Satellite System. The unique use of BeiDou geostationary satellites in this study provides more accurate calculations of disturbance traveling speed compared to other ground-based TEC data. The TEC results show that ionospheric disturbances passing over China after the eruption traveled at different speeds, indicating the need for further investigation into their mechanism.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2023)
Article
Geosciences, Multidisciplinary
Xing Meng, Michela Ravanelli, Attila Komjathy, Olga P. Verkhoglyadova
Summary: The Mw8.3 Illapel earthquake induced ionospheric disturbances, with stronger disturbances observed above the northern region of the epicenter than above the southern region. Modeling results show that 31% of the north-south asymmetry in disturbance magnitude is caused by different ground motion strengths, while the remaining 69% is attributed to the background ionospheric state.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Multidisciplinary Sciences
Boris Maletckii, Elvira Astafyeva
Summary: This study introduces a novel method for automatic detection and determination of spatio-temporal characteristics of CTID in ionospheric GNSS-data, along with real-time estimation of CTID source location and velocity. Additionally, the concept of real-time travel-time diagrams was developed for the first time to aid in verifying the correlation of CTID with the source and estimating the observed CTID propagation speed.
SCIENTIFIC REPORTS
(2021)
Article
Engineering, Aerospace
O. Laryunin
Summary: This study used ray tracing to simulate traveling ionospheric disturbances in a non-stratified ionosphere, investigated changes in ionogram traces due to disturbances, and demonstrated a method for determining TID parameters.
ADVANCES IN SPACE RESEARCH
(2021)
Article
Astronomy & Astrophysics
Ji Luo, Jiyao Xu, Kun Wu, Wenbin Wang, Chao Xiong, Wei Yuan
Summary: This study reports a special case of Medium Scale Traveling Ionospheric Disturbances (MSTIDs) over middle-latitude China on August 8, 2016. The MSTIDs were observed by multiple instruments, showing typical characteristics such as wavelength and phase velocity. The study also found that the propagation direction of MSTIDs may be influenced by ionospheric neutral winds.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2021)
Article
Astronomy & Astrophysics
V. V. Paznukhov, A. A. Sopin, V. G. Galushko, A. S. Kashcheyev, A. Koloskov, Y. M. Yampolski, A. Zalizovski
Summary: A statistical picture of the occurrence and characteristics of Traveling Ionospheric Disturbances (TIDs) over the Antarctic Peninsula is established. The results show that the observed climatology of ionospheric disturbances in the Antarctic Peninsula region varies significantly with the season, and two major types of disturbances, winter daytime and summer nighttime, can be differentiated based on their occurrence periods and characteristics.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2022)
Article
Geochemistry & Geophysics
Fuqing Huang, Jiuhou Lei, Yuichi Otsuka, Xiaoli Luan, Yu Liu, Jiahao Zhong, Xiankang Dou
Summary: This study characterized the variations in ionospheric irregularities and medium-scale traveling ionospheric disturbances (MSTIDs) at mid-latitudes over central China, and found different diurnal relationships between these phenomena using high-fidelity observations of total electron content (TEC) from a Beidou geostationary satellite during 2016-2017. Nighttime MSTIDs were found to have a significant impact on producing ionospheric irregularities, while daytime MSTIDs did not show the same effect.
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
(2021)
Article
Geosciences, Multidisciplinary
Jessica N. Ghent, Brendan W. Crowell
Summary: This paper investigates the impact of acoustic-gravity waves generated by the eruption of Tonga's Hunga Tonga-Hunga Ha'apai volcano on the Global Navigation Satellite System. By analyzing data from 818 ground stations, the study identifies supersonic acoustic waves, Lamb waves, and tsunamis with varying magnitudes and characteristics. The research also highlights the presence of a faster perturbation occurring one hour after the eruption, which potentially contributes to premature land arrivals of the tsunami. The arrival time of tsunami-generated disturbances aligns with deep-ocean observations.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Astronomy & Astrophysics
Shin-Chan Han, Simon McClusky, T. Dylan Mikesell, Lucie Rolland, Emile Okal, Craig Benson
Summary: Multiple passages of atmospheric waves were observed after the HTHH volcanic eruption, perturbing the ionosphere and producing TIDs. New observations of TIDs at high altitudes (>550 km) were made using CubeSat GPS tracking data, which provided complementary information to ground receivers due to their larger spatial coverage over a shorter period of time. The TIDs traveled globally and reached high altitudes, indicating a speed of approximately 350 m/s.
EARTH AND SPACE SCIENCE
(2023)
Article
Astronomy & Astrophysics
Ben Boyde, Alan Wood, Gareth Dorrian, Richard A. Fallows, David Themens, Jens Mielich, Sean Elvidge, Maaijke Mevius, Pietro Zucca, Bartosz Dabrowski, Andrzej Krankowski, Christian Vocks, Mario Bisi
Summary: Observations made using LOFAR reveal discrete pseudo-periodic features in the ionosphere, occurring within a period of approximately 10 minutes and lasting for about an hour. These features show strong frequency dependence, with broadening in time towards lower frequencies, and exhibit an overlaid pattern of diffraction fringes. Modelling the ionosphere as a thin phase screen with wave-like disturbances successfully replicates the observed features, suggesting their association with small-scale travelling ionospheric disturbances (TIDs).
JOURNAL OF SPACE WEATHER AND SPACE CLIMATE
(2022)
Article
Astronomy & Astrophysics
Neil R. Thomson, Mark A. Clilverd, James B. Brundell, Craig J. Rodger
Summary: VLF radio propagation recordings are used to determine the characteristics of the nighttime polar lower D region of the ionosphere. By analyzing VLF phase and amplitude recordings in the Arctic, researchers were able to determine the day-to-night changes near the equinoxes. The study found that the lower height of the ionosphere at night and its variability are consistent with energetic electron precipitation being the main source of ionization.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2021)
Article
Astronomy & Astrophysics
H. Nakata, K. Takaboshi, T. Takano, I Tomizawa
Summary: The vertical propagation of coseismic ionospheric disturbances associated with the foreshock of the Tohoku earthquake was examined using an HF Doppler sounding system. It is assumed that ground motion causes the acoustic mode wave to propagate upward, leading to vertical movement of neutral atmospheric particles.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2021)
Article
Geosciences, Multidisciplinary
E. S. Cramer, M. S. Briggs, N. Liu, B. Mailyan, J. R. Dwyer, H. K. Rassoul
GEOPHYSICAL RESEARCH LETTERS
(2017)
Article
Geosciences, Multidisciplinary
Shahab Arabshahi, Walid A. Majid, Joseph R. Dwyer, Hamid K. Rassoul
GEOPHYSICAL RESEARCH LETTERS
(2017)
Article
Geochemistry & Geophysics
Burcu C. Kosar, Elizabeth A. MacDonald, Nathan A. Case, Yongliang Zhang, Elizabeth J. Mitchell, Rodney Viereck
JOURNAL OF ATMOSPHERIC AND SOLAR-TERRESTRIAL PHYSICS
(2018)
Article
Meteorology & Atmospheric Sciences
Xuan-Min Shao, Cheng Ho, Michael Caffrey, Paul Graham, Brian Haynes, Gregory Bowers, William Blaine, Brenda Dingus, David Smith, Hamid Rassoul
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2018)
Article
Astronomy & Astrophysics
Robert Robinson, Yongliang Zhang, Katherine Garcia-Sage, Xiaohua Fang, Olga P. Verkhoglyadova, Chigomezyo Ngwira, Suzy Bingham, Burcu Kosar, Yihua Zheng, Stephen Kaeppler, Michael Liemohn, James B. Weygand, Geoffrey Crowley, Viacheslav Merkin, Ryan McGranaghan, Anthony J. Mannucci
SPACE WEATHER-THE INTERNATIONAL JOURNAL OF RESEARCH AND APPLICATIONS
(2019)
Article
Astronomy & Astrophysics
Konstantin V. Gamayunov, Kyungguk Min, Anthony A. Saikin, Hamid Rassoul
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2018)
Article
Astronomy & Astrophysics
B. C. Kosar, Elizabeth A. MacDonald, Nathan A. Case, Matthew Heavner
EARTH AND SPACE SCIENCE
(2018)
Article
Geosciences, Multidisciplinary
Levi D. Boggs, Ningyu Liu, Michael Peterson, Steven Lazarus, Michael Splitt, Frankie Lucena, Amitabh Nag, Hamid K. Rassoul
GEOPHYSICAL RESEARCH LETTERS
(2019)
Article
Environmental Sciences
Mahbubur Rahman, Pasan Hettiarachchi, Vernon Cooray, Joseph Dwyer, Vladimir Rakov, Hamid K. Rassoul
Article
Engineering, Electrical & Electronic
Naomi Watanabe, Amitabh Nag, Gerhard Diendorfer, Hannes Pichler, Wolfgang Schulz, Vladimir A. Rakov, Hamid K. Rassoul
IEEE TRANSACTIONS ON ELECTROMAGNETIC COMPATIBILITY
(2019)
Article
Astronomy & Astrophysics
Y. Nishimura, J. Yang, J. M. Weygand, W. Wang, B. Kosar, E. F. Donovan, V. Angelopoulos, L. J. Paxton, N. Nishitani
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2020)
Article
Geosciences, Multidisciplinary
Gregory S. Bowers, Xuan-Min Shao, William Blaine, Brenda Dingus, David M. Smith, Jeff Chaffin, John Ortberg, Hamid K. Rassoul, Cheng Ho, Lukas Nellen, Nissim Fraija, C. Alvarez, J. C. Arteaga-Velazquez, V. Baghmanyan, E. Belmont-Moreno, K. S. Caballero-Mora, A. Carraminana, S. Casanova, E. De la Fuente, M. M. Gonzalez, F. Hueyotl-Zahuantitla, O. Martinez, J. A. Matthews, E. Moreno, M. Newbold, E. G. Perez-Perez, I. Torres
Summary: The study reports anomalously long duration count rate bursts following the impact of cosmic ray showers, termed neutron bursts, near a LaBr3 scintillation detector in Mexico. The characteristic spectra and count rates of these bursts are well explained by neutron absorption in the ground, suggesting similar neutron bursts may be produced by other natural phenomena such as Terrestrial gamma ray flashes.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Meteorology & Atmospheric Sciences
Levi D. Boggs, Ningyu Liu, Amitabh Nag, T. Daniel Walker, Hugh J. Christian, Caitano. L. da Silva, Matthew Austin, Fernando Aguirre, Hamid K. Rassoul
Summary: This study utilized a high-speed optical spectrograph to investigate two natural lightning return strokes, revealing higher temperatures and larger temperature gradients at lower altitudes, along with faster cooling rates during the decay of the lightning channel.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2021)
Article
Geosciences, Multidisciplinary
Hamza Khounate, Amitabh Nag, Mathieu N. Plaisir, Abdullah Y. Imam, Christopher J. Biagi, Hamid K. Rassoul
Summary: The study presents high-speed video camera observations of three negative stepped leaders in cloud-to-ground lightning flashes, showing that the characteristics of space leaders are likely influenced by stepped-leader line-charge-density, possibly evolving differently in flashes with higher return-stroke peak currents.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Geosciences, Multidisciplinary
Amitabh Nag, Hamza Khounate, Kenneth L. Cummins, Dylan J. Goldberg, Abdullah Y. Imam, Mathieu N. Plaisir, Hamid K. Rassoul
Summary: We present time-correlated ultra-high-speed video camera and electromagnetic field measurements of the attachment processes in a natural negative cloud-to-ground stroke. The common streamer zone (CSZ) was first observed 2.52 & mu;s preceding the first frame showing the return stroke (RS) in progress, when the upward and downward leader-tips were 9.8 m apart. In the next frame, the two leaders were observed to have propagated toward each other within the CSZ, with their tips being 0.91 m apart. Our observations show with unprecedented precision/clarity that (a) the slow front in the field waveform is associated with the CSZ, and (b) the proper start of the RS is marked by the onset of the fast transition in the field waveform which occurs at the completion of the attachment processes (when the upward and downward leaders have merged).
GEOPHYSICAL RESEARCH LETTERS
(2023)