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Modeling Ionospheric TEC Using Gradient Boosting Based and Stacking Machine Learning Techniques Space Weather (IF 4.288) Pub Date : 2024-03-16 Ayanew Nigusie, Ambelu Tebabal, Roman Galas
Accurately predicting and modeling the ionospheric total electron content (TEC) can greatly improve the accuracy of satellite navigation and positioning and help to correct ionospheric delay. This study assesses the effectiveness of four different machine learning (ML) models in predicting hourly vertical TEC (VTEC) data for a single-station study over Ethiopia. The models employed include gradient
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Using ICON Satellite Data to Forecast Equatorial Ionospheric Instability Throughout 2022 Space Weather (IF 4.288) Pub Date : 2024-03-14 D. L. Hysell, A. Kirchman, B. J. Harding, R. A. Heelis, S. L. England, H. U. Frey, S. B. Mende
Numerical forecasts of plasma convective instability in the postsunset equatorial ionosphere are made based on data from the Ionospheric Connections Explorer satellite (ICON) following the method outlined in a previous study. Data are selected from pairs of successive orbits. Data from the first orbit in the pair are used to initialize and force a numerical forecast simulation, and data from the second
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On Generalized Additive Models for Representation of Solar EUV Irradiance Space Weather (IF 4.288) Pub Date : 2024-03-12 Daniel A. Brandt, Erick F. Vega, Aaron J. Ridley
In the context of space weather forecasting, solar EUV irradiance specification is needed on multiple time scales, with associated uncertainty quantification for determining the accuracy of downstream parameters. Empirical models of irradiance often rely on parametric fits between irradiance in several bands and various solar indices. We build upon these empirical models by using Generalized Additive
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Significant Midlatitude Bubble-Like Ionospheric Super-Depletion Structure (BLISS) and Dynamic Variation of Storm-Enhanced Density Plume During the 23 April 2023 Geomagnetic Storm Space Weather (IF 4.288) Pub Date : 2024-03-08 Ercha Aa, Shun-Rong Zhang, Shasha Zou, Wenbin Wang, Zihan Wang, Xuguang Cai, Philip J. Erickson, Anthea J. Coster
This paper investigates the midlatitude ionospheric disturbances over the American/Atlantic longitude sector during an intense geomagnetic storm on 23 April 2023. The study utilized a combination of ground-based observations (Global Navigation Satellite System total electron content and ionosonde) along with measurements from multiple satellite missions (GOLD, Swarm, Defense Meteorological Satellite
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Different Response of the Ionospheric TEC and EEJ to Ultra-Fast Kelvin Waves in the Mesosphere and Lower Thermosphere Space Weather (IF 4.288) Pub Date : 2024-03-07 Ruidi Sun, Sheng-Yang Gu, Xiankang Dou, Yusong Qin, Yafei Wei
We studied the response of ionospheric total electron content (TEC) and equatorial electrojet (EEJ) to the ultra-fast Kelvin wave (UFKW) at the equator in the mesosphere using zonal wind data obtained from TIMED Doppler Interferometer (TIDI), EEJ data over the monitoring station Jicamarca (12°S, 77°W) and global TEC maps. The least squares fitting method is utilized to perform a spectral analysis of
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Probabilistic Short-Term Solar Driver Forecasting With Neural Network Ensembles Space Weather (IF 4.288) Pub Date : 2024-03-05 Joshua D. Daniell, Piyush M. Mehta
Space weather indices are used to drive forecasts of thermosphere density, which directly affects objects in low-Earth orbit (LEO) through atmospheric drag force. A set of proxies and indices (drivers), F10.7, S10.7, M10.7, and Y10.7 are used as inputs by the JB2008, (https://doi.org/10.2514/6.2008-6438) thermosphere density model. The United States Air Force (USAF) operational High Accuracy Satellite
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ED-AttConvLSTM: An Ionospheric TEC Map Prediction Model Using Adaptive Weighted Spatiotemporal Features Space Weather (IF 4.288) Pub Date : 2024-03-06 Liangchao Li, Haijun Liu, Huijun Le, Jing Yuan, Haoran Wang, Yi Chen, Weifeng Shan, Li Ma, Chunjie Cui
In this paper, we propose a novel Total Electron Content (TEC) map prediction model, named ED-AttConvLSTM, using a Convolutional Long Short-Term Memory (ConvLSTM) network and attention mechanism based on encoder-decoder structure. The inclusion of the attention mechanism enhances the efficient utilization of spatiotemporal features extracted by the ConvLSTM, emphasizing the significance of crucial
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Characterization of the Ionospheric Vertical Error Correlation Lengths Based on Global Ionosonde Observations Space Weather (IF 4.288) Pub Date : 2024-03-05 L. Yuan, Timothy Kodikara, M. M. Hoque
Data assimilation is one of the most important approaches to monitoring the variations of ionospheric electron densities. The construction of the background error covariance matrix is an important component of ionospheric data assimilations. To construct the background error covariance matrix, the information about the spatial ionospheric correlations is required. We present a statistical analysis
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Long-Term Variations of Energetic Electrons Scattered by Signals From the North West Cape Transmitter Space Weather (IF 4.288) Pub Date : 2024-03-03 Jingle Hu, Zheng Xiang, Xin Ma, Yangxizi Liu, Junhu Dong, Deyu Guo, Binbin Ni
Very-low-frequency (VLF) signals emitted from ground-based transmitters for submarine communication can penetrate the ionosphere and leak into the magnetosphere, leading to electron precipitation via wave-particle interaction and thereby providing a potential means for radiation belt remediation. In this study, we systematically analyze the dependence of quasi-trapped electron fluxes scattered by signals
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Substorm-Time Ground dB/dt Variations Controlled by Interplanetary Shock Impact Angles: A Statistical Study Space Weather (IF 4.288) Pub Date : 2024-03-03 Denny M. Oliveira, James M. Weygand, John C. Coxon, Eftyhia Zesta
In this study, we investigate the effects caused by interplanetary (IP) shock impact angles on the subsequent ground dB/dt variations during substorms. IP shock impact angles have been revealed as a major factor controlling the subsequent geomagnetic activity, meaning that shocks with small inclinations with the Sun-Earth line are more likely to trigger higher geomagnetic activity resulting from nearly
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Modeling Equatorial to Mid-Latitudinal Global Night Time Ionospheric Plasma Irregularities Using Machine Learning Space Weather (IF 4.288) Pub Date : 2024-02-29 Ephrem Beshir Seba, Giovanni Lapenta
This study focuses on modeling the characteristics of nighttime topside Ionospheric Plasma Irregularities (PI) on a global scale. We utilize Random Forest (RF) and a one-dimensional Convolutional Neural Network (1D-CNN) model, incorporating data from the Swarm A, B, and C satellites, space weather data from the OMNIWeb data center, as well as zonal and meridional wind model data. Our objective is to
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Thermospheric Wind Response to March 2023 Storm: Largest Wind Ever Observed With a Fabry-Perot Interferometer in Tromsø, Norway Since 2009 Space Weather (IF 4.288) Pub Date : 2024-02-27 S. Oyama, H. Vanhamäki, L. Cai, A. Shinbori, K. Hosokawa, T. Sakanoi, K. Shiokawa, A. Aikio, I. I. Virtanen, Y. Ogawa, Y. Miyoshi, S. Kurita, N. Nishitani
Solar cycles 24–25 were quiet until a geomagnetic storm with a Sym-H index of −170 nT occurred in late March 2023. On March 23–24, a Fabry-Perot interferometer (FPI; 630 nm) in Tromsø, Norway, recorded the highest thermospheric wind speed of over 500 m/s since 2009. Comparisons with magnetometer readings in Scandinavia showed that a large amount of electromagnetic energy was transferred to the ion
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Issue Information Space Weather (IF 4.288) Pub Date : 2024-02-27
No abstract is available for this article.
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Observations of Geomagnetic Crochet at High-Latitudes Due To X1.5 Class Solar Flare on 3 July 2021 Space Weather (IF 4.288) Pub Date : 2024-02-23 S. S. Rao, Nandita Srivastava, Monti Chakraborty, Sandeep Kumar, D. Chakrabarty
On 3 July 2021, an X1.5 solar flare from the National Oceanic and Atmospheric Administration solar Active Region AR12838 (24°N, 88°W) occurred at 14:18 UT, peaked at 14:29 UT, and decayed at 14:34 UT. The study of this X1.5 solar flare is significant due to its unique geomagnetic crochet feature at high latitudes and its effective signature on Earth. The study examined X-rays, the extreme ultraviolet
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Validating a UK Geomagnetically Induced Current Model Using Differential Magnetometer Measurements Space Weather (IF 4.288) Pub Date : 2024-02-23 J. Hübert, C. D. Beggan, G. S. Richardson, N. Gomez-Perez, A. Collins, A. W. P. Thomson
Extreme space weather can damage ground-based infrastructure such as power lines, railways and gas pipelines through geomagnetically induced currents (GICs). Modeling GICs requires knowledge about the source magnetic field and the electrical conductivity structure of the Earth to calculate ground electric fields during enhanced geomagnetic activity. The electric field, in combination with detailed
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Unsupervised Anomaly Detection With Variational Autoencoders Applied to Full-Disk Solar Images Space Weather (IF 4.288) Pub Date : 2024-02-22 Marius Giger, André Csillaghy
Deep learning is successful in many fields due to its ability to learn strong feature representations without the need for hand-crafted features, resulting in models with high representational power. However, many of these models are based on supervised learning and therefore depend on the availability of large annotated data sets. These are often difficult to obtain because they require human input
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Climatology of Dayside E-Region Zonal Neutral Wind Shears From ICON-MIGHTI Observations Space Weather (IF 4.288) Pub Date : 2024-02-21 Minjing Li, Yue Deng, Brian J. Harding, Scott England
Large vertical shears in the E-region neutral zonal winds can lead to ion convergences and contribute to plasma irregularities, but climatological studies of vertical shears of horizontal winds in a global scale are lacking due to the limitations of data coverage. The Ionospheric Connection Explorer (ICON) Michelson Interferometer for Global High-resolution Thermospheric Imaging (MIGHTI) has provided
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Correcting Projection Effects in CMEs Using GCS-Based Large Statistics of Multi-Viewpoint Observations Space Weather (IF 4.288) Pub Date : 2024-02-19 Harshita Gandhi, Ritesh Patel, Vaibhav Pant, Satabdwa Majumdar, Sanchita Pal, Dipankar Banerjee, Huw Morgan
This study addresses the limitations of single-viewpoint observations of Coronal Mass Ejections (CMEs) by presenting results from a 3D catalog of 360 CMEs during solar cycle 24, fitted using the Graduated Cylindrical Shell (GCS) model. The data set combines 326 previously analyzed CMEs and 34 newly examined events, categorized by their source regions into active region (AR) eruptions, active prominence
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Using Solar Orbiter as an Upstream Solar Wind Monitor for Real Time Space Weather Predictions Space Weather (IF 4.288) Pub Date : 2024-02-20 R. Laker, T. S. Horbury, H. O’Brien, E. J. Fauchon-Jones, V. Angelini, N. Fargette, T. Amerstorfer, M. Bauer, C. Möstl, E. E. Davies, J. A. Davies, R. Harrison, D. Barnes, M. Dumbović
Coronal mass ejections (CMEs) can create significant disruption to human activities and systems on Earth, much of which can be mitigated with prior warning of the upstream solar wind conditions. However, it is currently extremely challenging to accurately predict the arrival time and internal structure of a CME from coronagraph images alone. In this study, we take advantage of a rare opportunity to
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Ionospheric Disturbances Generated by the 2015 Calbuco Eruption: Comparison of GITM-R Simulations and GNSS Observations Space Weather (IF 4.288) Pub Date : 2024-02-17 J. Tyska, Y. Deng, S. Zhang, C. Y. Lin
Volcanic eruptions provide broad spectral forcing to the atmosphere and understanding the primary mechanisms that are relevant to explain the variety in waveform characteristics in the Ionosphere-Thermosphere (IT) is still an important open question for the community. In this study, Global Navigation Satellite System (GNSS) Total Electron Content (TEC) data are analyzed and compared to simulations
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An Improved Stochastic Model for the Geodetic GNSS Receivers Under Ionospheric Scintillation at Low Latitudes Space Weather (IF 4.288) Pub Date : 2024-02-18 Xiaomin Luo, Yingzong Lin, Xiaolei Dai, Shaofeng Bian, Dezhong Chen
The receiver tracking error stochastic (RTES) model can improve GNSS precise point positioning (PPP) performance under ionospheric scintillation. However, it relies on scintillation products derived from ionospheric scintillation monitoring receivers (ISMRs), which means the RTES model cannot be used for abundant geodetic GNSS receivers. In this study, we propose an improved RTES, referred to as Impr_RTES
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The Impact of Non-Equilibrium Plasma Distributions on Solar Wind Measurements by Vigil's Plasma Analyser Space Weather (IF 4.288) Pub Date : 2024-02-20 H. Zhang, D. Verscharen, G. Nicolaou
In order to protect society from space weather impacts, we must monitor space weather and obtain early warnings for extreme events if possible. For this purpose, the European Space Agency is currently preparing to launch the Vigil mission toward the end of this decade as a space-weather monitor at the fifth Lagrange point of the Sun–Earth system. Vigil will carry, amongst other instruments, the Plasma
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Improving Thermospheric Density Predictions in Low-Earth Orbit With Machine Learning Space Weather (IF 4.288) Pub Date : 2024-02-03 Giacomo Acciarini, Edward Brown, Tom Berger, Madhulika Guhathakurta, James Parr, Christopher Bridges, Atılım Güneş Baydin
Thermospheric density is one of the main sources of uncertainty in the estimation of satellites' position and velocity in low-Earth orbit. This has negative consequences in several space domains, including space traffic management, collision avoidance, re-entry predictions, orbital lifetime analysis, and space object cataloging. In this paper, we investigate the prediction accuracy of empirical density
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Quantifying Uncertainties in the Quiet-Time Ionosphere-Thermosphere Using WAM-IPE Space Weather (IF 4.288) Pub Date : 2024-02-03 Weijia Zhan, Alireza Doostan, Eric Sutton, Tzu-Wei Fang
This study presents a data-driven approach to quantify uncertainties in the ionosphere-thermosphere (IT) system due to varying solar wind parameters (drivers) during quiet conditions (Kp < 4) and fixed solar radiation and lower atmospheric conditions representative of 16 March 2013. Ensemble simulations of the coupled Whole Atmosphere Model with Ionosphere Plasmasphere Electrodynamics (WAM-IPE) driven
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An Examination of Geomagnetic Induction in Submarine Cables Space Weather (IF 4.288) Pub Date : 2024-02-01 David H. Boteler, Shibaji Chakraborty, Xueling Shi, Michael D. Hartinger, Xuan Wang
Submarine cables have experienced problems during extreme geomagnetic disturbances because of geomagnetically induced voltages adding or subtracting from the power feed to the repeaters. This is still a concern for modern fiber-optic cables because they contain a copper conductor to carry power to the repeaters. This paper provides a new examination of geomagnetic induction in submarine cables and
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Issue Information Space Weather (IF 4.288) Pub Date : 2024-01-29
No abstract is available for this article.
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Forecasting of Global Ionosphere Maps With Multi-Day Lead Time Using Transformer-Based Neural Networks Space Weather (IF 4.288) Pub Date : 2024-01-30 Chung-Yu Shih, Cissi Ying-tsen Lin, Shu-Yu Lin, Cheng-Hung Yeh, Yu-Ming Huang, Feng-Nan Hwang, Chia-Hui Chang
Ionospheric total electron content (TEC) is a key indicator of the space environment. Geophysical forcing from above and below drives its spatial and temporal variations. A full understanding of physical and chemical principles, available and well-representable driving inputs, and capable computational power are required for physical models to reproduce simulations that agree with observations, which
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Mapping Geoelectric Field Hazards in Ireland Space Weather (IF 4.288) Pub Date : 2024-02-01 John Malone-Leigh, Joan Campanyà, Peter T. Gallagher, Jim Hodgson, Colin Hogg
Geoelectric fields are generated at the Earth's surface and can lead to the induction of hazardous geomagnetically induced currents (GIC) in infrastructure like power grids, railways and pipelines during geomagnetic storms. Magnitude and orientation of the geoelectric fields, in relation to the infrastructure, are key features needed to determine the intensity of GIC. Here, we developed the first geoelectric
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A Substorm-Dependent Negative Limit of Non-Eclipse Surface Charging of a Chinese Geosynchronous Satellite Space Weather (IF 4.288) Pub Date : 2024-01-30 Zhiyi Fu, Zhenpeng Su, Bin Miao, Zhiyong Wu, Yiren Li, Kai Liu, Xu Shan, Yuming Wang
Surface charging is one of the most common causes of spacecraft anomalies. When and to what potential the spacecraft is charged are two important questions in space weather. Here, for a Chinese geosynchronous navigation satellite, we infer the extreme negative surface charging potentials from the ion differential fluxes measured by a low-energy ion spectrometer. Without the solar eclipse effect away
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The Daytime Variations of Thermospheric Temperature and Neutral Density Over Beijing During Minor Geomagnetic Storm on 3–4 February 2022 Space Weather (IF 4.288) Pub Date : 2024-01-30 Shaoyang Li, Zhipeng Ren, Tingting Yu, Guangming Chen, Guozhu Li, Biqiang Zhao, Xinan Yue, Yong Wei
On 3 February 2022, 38 satellites launched by SpaceX re-entered the atmosphere and were subsequently destroyed. An investigation found that a minor geomagnetic storm occurred on 3–4 February 2022 led to a neutral density enhancement and large atmospheric drag. To better understand the responses of the thermosphere to geomagnetic storms, the method proposed by Li et al. (2023, https://doi.org/10.1029/2022ja030988)
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Statistical Characteristics of Total Electron Content Intensifications on Global Ionospheric Maps Space Weather (IF 4.288) Pub Date : 2024-01-24 X. Meng, O. P. Verkhoglyadova, S. C. Chapman, N. W. Watkins, M. Cafolla
Global ionospheric total electron content (TEC) maps exhibit TEC intensifications and depletions of various sizes and shapes. Characterizing key features on TEC maps and understanding their dynamic coupling with external drivers can significantly benefit space weather forecasting. However, comprehensive analysis of ionospheric structuring over decades of TEC maps is currently lacking due to large data
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Prediction of Ionograms With/Without Spread-F at Hainan by a Combined Spatio-Temporal Neural Network Space Weather (IF 4.288) Pub Date : 2024-01-24 Pengdong Gao, Jinhui Cai, Zheng Wang, Chu Qiu, Guojun Wang, Quan Qi, Bo Wang, Jiankui Shi, Xiao Wang, Kai Ding
An intelligent high-definition and short-term prediction of ionograms with/without Spread-F for the observation at Hainan (19.5°N, 109.1°E, magnetic 11°N) is presented in this paper, which comprises a spatio-temporal ConvGRU network and a super-resolution EDSR network. Our prediction is based on spatio-temporal features in the ionogram graph only. There are 469,227 ionograms classified into 5 categories
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Collection, Collation, and Comparison of 3D Coronal CME Reconstructions Space Weather (IF 4.288) Pub Date : 2024-01-23 C. Kay, E. Palmerio
Predicting the impacts of coronal mass ejections (CMEs) is a major focus of current space weather forecasting efforts. Typically, CME properties are reconstructed from stereoscopic coronal images and then used to forward model a CME's interplanetary evolution. Knowing the uncertainty in the coronal reconstructions is then a critical factor in determining the uncertainty of any predictions. A growing
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Can We Intercalibrate Satellite Measurements by Means of Data Assimilation? An Attempt on LEO Satellites Space Weather (IF 4.288) Pub Date : 2024-01-24 Angélica M. Castillo, Yuri Y. Shprits, Nikita A. Aseev, Artem Smirnov, Alexander Drozdov, Sebastian Cervantes, Ingo Michaelis, Marina García Peñaranda, Dedong Wang
Low Earth Orbit satellites offer extensive data of the radiation belt region, but utilizing these observations is challenging due to potential contamination and difficulty of intercalibration with spacecraft measurements at Highly Elliptic Orbit that can observe all equatorial pitch-angles. This study introduces a new intercalibration method for satellite measurements of energetic electrons in the
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Long-Term Variation of the Galactic Cosmic Ray Radiation Dose Rates Space Weather (IF 4.288) Pub Date : 2024-01-23 D. Lyu, G. Qin, Z.-N. Shen
In this work, a model for calculating the galactic cosmic rays (GCRs) radiation dose rate is developed. The model is based on a GCR modulation model, which is established by Shen and Qin, and the fluence-dose conversion coefficients (FDCCs) published by the International Commission on Radiological Protection (ICRP). With the model, the radiation absorbed dose rate of GCRs near the lunar surface over
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Characterization of Scintillation Events With Basis on L1 Transmissions From Geostationary SBAS Satellites Space Weather (IF 4.288) Pub Date : 2024-01-20 Alison Moraes, Jonas Sousasantos, Emanoel Costa, Bruno Augusto Pereira, Fabiano Rodrigues, João Francisco Galera Monico
Signals recorded by two stations in the Brazilian region: [Fortaleza (3.74°S, 38.57°W) and Inconfidentes (22.31°S, 46.32°W)], receiving L1 transmissions from different geostationary satellites, were used to evaluate the amplitude scintillation index S4 and several characteristics of scintillation events (continuous record with S4 > 0.2) during nighttime hours (18:00 LT–02:00 LT) in the years 2014–2016
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A Transfer Learning Method to Generate Synthetic Synoptic Magnetograms Space Weather (IF 4.288) Pub Date : 2024-01-21 Xiaoyue Li, Senthamizh Pavai Valliappan, Daria Shukhobodskaia, Mark D. Butala, Luciano Rodriguez, Jasmina Magdalenic, Véronique Delouille
Current magnetohydrodynamics (MHD) models largely rely on synoptic magnetograms, such as the ones produced by the Global Oscillation Network Group (GONG). Magnetograms are currently available mostly from the front side of the Sun, which significantly reduces the accuracy of MHD modeling. Extreme Ultraviolet (EUV) images can instead be obtained from other vantage points. To investigate the potential
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Refined Modeling of Geoeffective Fast Halo CMEs During Solar Cycle 24 Space Weather (IF 4.288) Pub Date : 2024-01-17 E. Yordanova, M. Temmer, M. Dumbović, C. Scolini, E. Paouris, A. L. E. Werner, A. P. Dimmock, L. Sorriso-Valvo
The propagation of geoeffective fast halo coronal mass ejections (CMEs) from solar cycle 24 has been investigated using the European Heliospheric Forecasting Information Asset (EUHFORIA), ENLIL, Drag-Based Model (DBM) and Effective Acceleration Model (EAM) models. For an objective comparison, a unified set of a small sample of CME events with similar characteristics has been selected. The same CME
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F10.7 Daily Forecast Using LSTM Combined With VMD Method Space Weather (IF 4.288) Pub Date : 2024-01-17 Yuhang Hao, Jianyong Lu, Guangshuai Peng, Ming Wang, Jingyuan Li, Guanchun Wei
The F10.7 solar radiation flux is a well-known parameter that is closely linked to solar activity, serving as a key index for measuring the level of solar activity. In this study, the Variational Mode Decomposition (VMD) and Long Short-term Memory (LSTM) network are combined to construct a VMD-LSTM model for predicting F10.7 values. The F10.7 sequence is decomposed into several intrinsic mode functions
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Detection and Classification of Sporadic E Using Convolutional Neural Networks Space Weather (IF 4.288) Pub Date : 2024-01-12 J. A. Ellis, D. J. Emmons, M. B. Cohen
In this work, convolutional neural networks (CNN) are developed to detect and characterize sporadic E (Es), demonstrating an improvement over current methods. This includes a binary classification model to determine if Es is present, followed by a regression model to estimate the Es ordinary mode critical frequency (foEs), a proxy for the intensity, along with the height at which the Es layer occurs
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Sudden Commencements and Geomagnetically Induced Currents in New Zealand: Correlations and Dependance Space Weather (IF 4.288) Pub Date : 2024-01-10 A. W. Smith, C. J. Rodger, D. H. Mac Manus, I. J. Rae, A. R. Fogg, C. Forsyth, P. Fisher, T. Petersen, M. Dalzell
Changes in the Earth's geomagnetic field induce geoelectric fields in the solid Earth. These electric fields drive Geomagnetically Induced Currents (GICs) in grounded, conducting infrastructure. These GICs can damage or degrade equipment if they are sufficiently intense—understanding and forecasting them is of critical importance. One of the key magnetospheric phenomena are Sudden Commencements (SCs)
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Deep Learning-Based Regional Ionospheric Total Electron Content Prediction—Long Short-Term Memory (LSTM) and Convolutional LSTM Approach Space Weather (IF 4.288) Pub Date : 2024-01-09 Se-Heon Jeong, Woo Kyoung Lee, Hyosub Kil, Soojeong Jang, Jeong-Heon Kim, Young-Sil Kwak
This study evaluates the performance of deep learning approach in the prediction of the ionospheric total electron content (TEC) during magnetically quiet periods. Two deep learning techniques, long short-term memory (LSTM) and convolutional LSTM (ConvLSTM), are employed to predict TEC values 24 hr ahead in the vicinity of the Korean Peninsula (26.5°–40°N, 121°–134.5°E). The LSTM method predicts TEC
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One-Dimensional Variational Ionospheric Retrieval Using Radio Occultation Bending Angles: 2. Validation Space Weather (IF 4.288) Pub Date : 2024-01-09 S. Elvidge, S. B. Healy, I. D. Culverwell
Culverwell et al. (2023, https://doi.org/10.22541/essoar.168614409.98641332) described a new one-dimensional variational (1D-Var) retrieval approach for ionospheric GNSS radio occultation (GNSS-RO) measurements. The approach maps a one-dimensional ionospheric electron density profile, modeled with multiple “Vary-Chap” layers, to bending angle space. This paper improves the computational performance
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Investigation of Ionospheric Small-Scale Plasma Structures Associated With Particle Precipitation Space Weather (IF 4.288) Pub Date : 2024-01-09 F. Enengl, L. Spogli, D. Kotova, Y. Jin, K. Oksavik, N. Partamies, W. J. Miloch
We investigate the role of auroral particle precipitation in small-scale (below hundreds of meters) plasma structuring in the auroral ionosphere over the Arctic. In this scope, we analyze together data recorded by an Ionospheric Scintillation Monitor Receiver (ISMR) of Global Navigation Satellite System (GNSS) signals and by an All-Sky Imager located in Longyearbyen, Svalbard (Norway). We leverage
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One-Dimensional Variational Ionospheric Retrieval Using Radio Occultation Bending Angles: 1. Theory Space Weather (IF 4.288) Pub Date : 2024-01-09 I. D. Culverwell, S. B. Healy, S. Elvidge
A new one-dimensional variational (1D-Var) retrieval method for ionospheric GNSS radio occultation (GNSS-RO) measurements is described. The forward model implicit in the retrieval calculates the bending angles produced by a one-dimensional ionospheric electron density profile, modeled with multiple “Vary-Chap” layers. It is demonstrated that gradient based minimization techniques can be applied to
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Study on Test-Mass Charging for Taiji Gravitational Wave Observatory Space Weather (IF 4.288) Pub Date : 2024-01-05 Ruilong Han, Minghui Cai, Tao Yang, Liangliang Xu, Qing Xia, Xinyu Jia, Dawei Gao, Mengyao Li, Longlong Zhang, Hongwei Li, Jianwei Han
Taiji is proposed as a space-based gravitational wave (GW) observatory consisting of three spacecraft in a heliocentric orbit meanwhile with the distance of 3 million kilometers ahead of the Earth at about 20°. Free-falling test masses (TMs) are a key component of the interferometer for space-based GW detection in the 0.1mHz–1 Hz frequency range. Exposure to energetic particles in the space environment
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Evaluation of the Exospheric Temperature Modeling From Different Empirical Orthogonal Functions Space Weather (IF 4.288) Pub Date : 2024-01-05 Xu Yang, Libin Weng, Jiuhou Lei, Xiaoqian Zhu, Haibing Ruan, Dexin Ren, Zhongli Li, Ruoxi Li, Liangjie Chen
In this paper, we constructed the Exospheric Temperature Models (ETM) on the basis of CHAMP and GRACE data using different empirical orthogonal functions (EOFs). The EOFs of the exospheric temperature can be derived either from satellite data directly or from the outputs of the Thermosphere Ionosphere Electrodynamics General Circulation Model (TIEGCM) and MSIS models by applying the Principal Component
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Issue Information Space Weather (IF 4.288) Pub Date : 2024-01-02
No abstract is available for this article.
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Storm-Time Characteristics of Ionospheric Model (MSAP) Based on Multi-Algorithm Fusion Space Weather (IF 4.288) Pub Date : 2024-01-02 Zhou Chen, Kang Wang, Haimeng Li, Wenti Liao, Rongxin Tang, Jing-song Wang, Xiaohua Deng
Geomagnetic storms induce ionospheric disturbances, affecting short-wave radio communication systems. Accurate ionospheric total electron content (TEC) prediction is vital for accurately describing the short-wave radio environment of the ionosphere. We use the Multi-Step Auxiliary Prediction (MSAP) model, a deep learning algorithm, to forecast TEC during geomagnetic storms. The MSAP model integrates
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Machine Learning-Based Emulator for the Physics-Based Simulation of Auroral Current System Space Weather (IF 4.288) Pub Date : 2024-01-02 Ryuho Kataoka, Aoi Nakamizo, Shinya Nakano, Shigeru Fujita
Using a machine learning technique called echo state network (ESN), we have developed an emulator to model the physics-based global magnetohydrodynamic simulation results of REPPU (REProduce Plasma Universe) code. The inputs are the solar wind time series with date and time, and the outputs are the time series of the ionospheric auroral current system in the form of two-dimensional (2D) patterns of
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Horizontal Spatial Correlation of the Ionospheric Day-To-Day Variations at Low Latitudes Based on GOLD Nmax Data Space Weather (IF 4.288) Pub Date : 2023-12-27 Jiawen Chen, Jiahao Zhong, Yongqiang Hao, Xin Wan, Qiaoling Li, Zijing Tang, Xingyan Song, Hao Han, Kang Wang, Jiawei Kuai, Aojun Ren
Peak electron density data derived from GOLD measurements during 2018–2022 are used to analyze the magnitudes and correlations of ionospheric diurnal variability at low latitudes. The correlation distance describes the correlations between spatial locations and is defined in this paper as the angular separation at which the correlation coefficient decreases from 1 to 0.7. Variations in correlation
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Atmospheric Ionizations by Solar X-Rays, Solar Protons, and Radiation Belt Electrons in September 2017 Space Weather Event Space Weather (IF 4.288) Pub Date : 2023-12-27 Kiyoka Murase, Ryuho Kataoka, Takanori Nishiyama, Kaoru Sato, Masaki Tsutsumi, Yoshimasa Tanaka, Yasunobu Ogawa, Tatsuhiko Sato
Energetic particles from space deposit their energies on the Earth's atmosphere and contribute to variations in the concentration of neutral components such as ozone which controls the atmospheric temperature balance. Comprehensive understandings of their global impact on the atmosphere require whole pictures of spatiotemporal ionization distributions due to them. We first attempt to evaluate and summarize
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Forward-Looking Study of Solar Maximum Impact in 2025: Effects of Satellite Navigation Failure on Aviation Network Operation in the Greater Bay Area, China Space Weather (IF 4.288) Pub Date : 2023-12-27 Dabin Xue, Jian Yang, Zhizhao Liu, Wei Cong
Satellite navigation based on the Global Navigation Satellite System can provide aircraft with more precise guidance and increase flight efficiency. However, severe space weather events can cause satellite navigation failure due to the dramatic increase in total electron content and irregularities in the ionosphere. Consequently, ground navigation has to be used to replace satellite navigation, increasing
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Analysis of the Geoelectric Field in Sweden Over Solar Cycles 23 and 24: Spatial and Temporal Variability During Strong GIC Events Space Weather (IF 4.288) Pub Date : 2023-12-27 V. Lanabere, A. P. Dimmock, L. Rosenqvist, L. Juusola, A. Viljanen, A. Johlander, E. Odelstad
Geomagnetic storms can produce large perturbations on the Earth magnetic field. Through complex magnetosphere-ionosphere coupling, the geoelectric field (E) and geomagnetic field (B) are highly perturbed. The E is the physical driver of geomagnetically induced currents. However, a statistical study of the E in Sweden has never been done before. We combined geomagnetic data from the International Monitor
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RAM-SCB Runs on Request at CCMC Space Weather (IF 4.288) Pub Date : 2023-12-26 Steven K. Morley, Vania K. Jordanova, Yihua Zheng, Maksym Petrenko
The Ring current–Atmosphere interactions Model (RAM) with Self-Consistent magnetic (B) field (SCB) combines a large-scale kinetic model of ring current plasma with a three-dimensional (3-D) force-balanced model of the terrestrial magnetic field. RAM-SCB simulates the evolution of major ion species (H+, O+, and He+ by default) and electrons as a function of azimuth, radial distance, energy, and pitch
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Topside Electron Density Modeling Using Neural Network and Empirical Model Predictions Space Weather (IF 4.288) Pub Date : 2023-12-19 S. Dutta, M. B. Cohen
We model the electron density in the topside of the ionosphere with an improved machine learning (ML) model and compare it to existing empirical models, specifically the International Reference Ionosphere (IRI) and the Empirical-Canadian High Arctic Ionospheric Model (E-CHAIM). In prior work, an artificial neural network (NN) was developed and trained on two solar cycles worth of Defense Meteorological
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A High Accuracy Spatial Reconstruction Method Based on Surface Theory for Regional Ionospheric TEC Prediction Space Weather (IF 4.288) Pub Date : 2023-12-19 Jian Wang, Yi-ran Liu, Ya-fei Shi
In order to achieve more accurate spatial reconstruction of ionospheric total electron content (TEC) and promote improved satellite positioning and ranging applications, a high accuracy spatial reconstruction (HASR) method for TEC is proposed based on the surface theory. The core theory of this method is as follows: (a) Any surface can be uniquely determined by its first and second fundamental quantities;
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Modeling Pipe to Soil Potentials From Geomagnetic Storms in Gas Pipelines in New Zealand Space Weather (IF 4.288) Pub Date : 2023-12-19 Tim Divett, Malcolm Ingham, Gemma Richardson, Mark Sigley, Craig J. Rodger
Gas pipelines can experience elevated pipe to soil potentials (PSPs) during geomagnetic disturbances due to the induced geoelectric field. Gas pipeline operators use cathodic protection to keep PSPs between −0.85 and −1.2 V to prevent corrosion of the steel pipes and disbondment of the protective coating from the pipes. We have developed a model of the gas pipelines in the North Island of New Zealand
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Radio Absorption in the Nightside Ionosphere of Mars During Solar Energetic Particle Events Space Weather (IF 4.288) Pub Date : 2023-12-19 Y. Harada, Y. Nakamura, B. Sánchez-Cano, M. Lester, N. Terada, F. Leblanc
Characterization, understanding, and prediction of the Martian radio environment are of increasing importance to the forthcoming human exploration of Mars. Here we investigate 3–5 MHz radio absorption in the nightside ionosphere of Mars caused by enhanced ionization at <100 km altitudes during solar energetic particle (SEP) events. We conduct a quantitative analysis of radio absorption and SEP flux
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Validating Ionospheric Models Against Technologically Relevant Metrics Space Weather (IF 4.288) Pub Date : 2023-12-15 A. T. Chartier, J. Steele, G. Sugar, D. R. Themens, S. K. Vines, J. D. Huba
New, open access tools have been developed to validate ionospheric models in terms of technologically relevant metrics. These are ionospheric errors on GPS 3D position, HF ham radio communications, and peak F-region density. To demonstrate these tools, we have used output from Sami is Another Model of the Ionosphere (SAMI3) driven by high-latitude electric potentials derived from Active Magnetosphere