Results 21 to 30 of about 792,786 (268)

Multi-instrumented observations of the equatorial F-region during June solstice: large-scale wave structures and spread-F

Progress in Earth and Planetary Science, 2018
Typical equatorial spread-F events are often said to occur during post-sunset, equinox conditions in most longitude sectors. Recent studies, however, have found an unexpected high occurrence of ionospheric F-region irregularities during June solstice ...
Fabiano S. Rodrigues, Dustin A. Hickey, Weijia Zhan, Carlos R. Martinis, Bela G. Fejer, Marco A. Milla, Juan F. Arratia   +6 more
doaj   +1 more source

Equatorial spread-F forecasting model with local factors using the long short-term memory network

Earth, Planets and Space, 2023
The predictability of the nighttime equatorial spread-F (ESF) occurrences is essential to the ionospheric disturbance warning system. In this work, we propose ESF forecasting models using two deep learning techniques: artificial neural network (ANN) and ...
Phimmasone Thammavongsy, Pornchai Supnithi, Lin Min Min Myint, Kornyanat Hozumi, Donekeo Lakanchanh   +4 more
doaj   +1 more source

One-hour-ahead forecasting of ionogram morphology and spread-F signatures using a spatial group-wise enhanced ConvTransformer

Journal of Space Weather and Space Climate
The Digisonde Portable Sounder (DPS) ionosonde at Hainan Station (19.5°N, 109.1°E; magnetic latitude: 11°N) has been monitoring ionospheric conditions since 2002, routinely recording ionospheric plasma profiles, sporadic E layers, and Spread-F structures
Cai Jinhui, Gao Pengdong, Wang Zheng, Wang Bo, Wang Guojun, Qi Quan, Qiu Chu, Ye Yudong, Shi Jiankui, Wang Xiao   +9 more
doaj   +1 more source

Density enhancements associated with equatorial spread F [PDF]

Annales Geophysicae, 2010
Forces governing the three-dimensional structure of equatorial spread-F (ESF) plumes are examined using the NRL SAMI3/ESF three-dimensional simulation code.
J. Krall, J. D. Huba, G. Joyce, T. Yokoyama   +3 more
doaj   +1 more source

Longitudinal differences in the statistical characteristics of ionospheric spread-F occurrences at midlatitude in Eastern Asia

Earth, Planets and Space, 2019
Spread-F is known as the electron density inhomogeneous structures in F layer of ionosphere and can usually be classified as frequency spread-F (FSF) and range spread-F (RSF).
Ning Wang, Lixin Guo, Zonghua Ding, Zhenwei Zhao, Zhengwen Xu, Tong Xu, Yanli Hu   +6 more
doaj   +1 more source

Global Modeling of Equatorial Spread F with SAMI3/WACCM‐X

Geophysical Research Letters, 2020
We report the first results of a global ionosphere/thermosphere simulation study that self‐consistently generates large‐scale equatorial spread F (ESF) plasma bubbles in the postsunset ionosphere.
J. D. Huba, H.‐L. Liu
doaj   +1 more source

Multistation digisonde observations of equatorial spread F in South America [PDF]

Annales Geophysicae, 2004
Directional ionogram and F-region drift observations were conducted at seven digisonde stations in South America during the COPEX campaign from October to December 2002.
B. W. Reinisch, M. Abdu, I. Batista, G. S. Sales, G. Khmyrov, T. A. Bullett, J. Chau, V. Rios   +7 more
doaj   +1 more source

Ionosonde Observations of Spread F and Spread Es at Low and Middle Latitudes during the Recovery Phase of the 7–9 September 2017 Geomagnetic Storm

Remote Sensing, 2021
This study presents observations of nighttime spread F/ionospheric irregularities and spread Es at low and middle latitudes in the South East Asia longitude of China sectors during the recovery phase of the 7–9 September 2017 geomagnetic storm.
Lehui Wei, Chunhua Jiang, Yaogai Hu, Ercha Aa, Wengeng Huang, Jing Liu, Guobin Yang, Zhengyu Zhao   +7 more
doaj   +1 more source

A comparative study of GPS ionospheric scintillations and ionogram spread F over Sanya [PDF]

Annales Geophysicae, 2015
We analyze the data recorded during December 2011–November 2012 by a digital ionosonde and a GPS (Global Positioning System) scintillation and (total electron content) TEC receiver collocated at Sanya (109.6° E, 18.3° N; dip lat.
Y. Zhang, Y. Zhang, Y. Zhang, W. Wan, W. Wan, G. Li, G. Li, L. Liu, L. Liu, L. Hu, L. Hu, B. Ning, B. Ning   +12 more
doaj   +1 more source

Observations of Unusual Daytime Range Spread F at Middle Latitude During the Afternoon Hours

Space Weather, 2021
In this study, an unusual daytime range spread F event recorded by the ionosonde installed at Zhangye (ZHY, 39.4°N, 100.13°E, dip latitude 29.65°N) station during the afternoon of December 23, 2016 was presented.
Lehui Wei, Chunhua Jiang, Ting Lan, Wenxuan Wang, Hua Shen, Ercha Aa, Wengeng Huang, Jing Liu, Guobin Yang, Yaogai Hu, Zhengyu Zhao   +10 more
doaj   +1 more source