Energetic electrons inside Earth's Van Allen belts pose a major radiation threat to space-borne electronics that often play vital roles in modern society. Ultra-relativistic electrons with energies greater than or equal to two megaelectron-volt (MeV) are of particular interest, and thus forecasting these ≥2 MeV electrons has a significant meaning to all space sectors. Here, we update the latest development

The evolution and propagation of coronal mass ejections (CMEs) in interplanetary space is still not well understood. As a consequence, accurate arrival time and arrival speed forecasts are an unsolved problem in space weather research. In this study, we present the ELlipse Evolution model based on HI observations (ELEvoHI) and introduce a deformable front to this model. ELEvoHI relies on heliospheric

The threat of Geomagnetically Induced Currents (GICs) driven by severe Space Weather looms over technological systems such as power grids. Assessing their vulnerability is thus vital to avoid damages or even disruption of the electrical power supply. This endeavor, however, entails an interdisciplinary approach, ranging from the characterization of the geoelectrical structure of the Earth beneath and

Large geomagnetically induced currents (GICs) pose a risk to ground based infrastructure such as power networks. Large GICs may be induced when the rate of change of the ground magnetic field is significantly elevated. We assess the ability of three different machine learning model architectures to process the time history of the incoming solar wind and provide a probabilistic forecast as to whether

The 400 worst-case severe environments for surface charging detected at Los Alamos National Laboratory satellites during the years of 1990–2005 as binned by the definitions of four criteria developed by Matéo-Vélez et al. (2018, https://doi.org/10.1002/2017sw001689) and the solar wind and Interplanetary Magnetic Field (IMF) parameters and geomagnetic activity indices are analyzed. The conducted analysis

This study investigates the solar origins of the 26th August 2018 geomagnetic storm and the responses of the interplanetary medium and equatorial/low-latitude ionosphere to it. We used a multi-instrument approach, with observations right from the solar surface to the Earth. Our results showed that the G3 geomagnetic storm of 26th August, 2018 was initiated by a solar filament eruption of 20th August

The Empirical Canadian High Artic Ionospheric Model (E-CHAIM) provides the four-dimensional ionosphere electron density at northern high latitudes (>50⁰ geomagnetic latitude). Despite its emergence as the most reliable model for high-latitude ionosphere density, there remain significant deficiencies in E-CHAIM’s representation of the lower ionosphere (below ∼200 km) due to a sparsity of reliable measurements

As NASA prepares for longer duration missions beyond the geomagnetic field, the possibility of intensifying galactic cosmic ray (GCR) exposure raises possible concerns for mission planning and crew health and safety. Spaceborne satellite measurements have exhibited increasing GCR intensities and dose-rates over the past few solar minima, consistent with related heliospheric magnetic field data. Surrogate

Several techniques have been developed in the last two decades to forecast the occurrence of Solar Proton Events (SPEs), mainly based on the statistical association between the 10 MeV proton flux and precursor parameters. The Empirical model for Solar Proton Events Real Time Alert (ESPERTA; Laurenza et al., 2009) provides a quite good and timely prediction of SPEs after the occurrence of $\geq$M2 soft

Ionospheric disturbance dynamo is one of the main processes that causes perturbations in the upper atmosphere during a magnetic storm. We present a new method, based on the least square fitting, for estimation of the magnetic signatures associated with ionospheric disturbance currents. Using a wavelet semblance analysis, the durations of disturbance dynamo electric fields have been investigated at

The Earth-Sun Lagrangian point 4 is a meta-stable location at 1 AU from the Sun, 60° ahead of Earth's orbit. It has an uninterrupted view of the solar photosphere centered on W60, the Earth's nominal magnetic field connection to the Sun. Such a mission on its own would serve as a solar remote sensing observatory that would oversee the entire solar radiation hemisphere with significant relevance for

To advance our understanding of the global response of the ionospheric total electron content (TEC) to various external drivers, we apply entropy-based information theory to quantify contributions of solar, interplanetary, and lower atmospheric drivers to the global ionospheric state described by the Global Ionospheric Map (GIM). By computing normalized transfer entropy on 18 years of GIM TEC, F10

Using a time series of geomagnetic storm events between 1957 and 2019, obtained by selecting storms where −50 nT, we have analyzed the probability of occurrence of moderate, intense, and severe events. Considering that geomagnetic storms can be modeled as stochastic processes with a log-normal probability distribution over their minimum index, the dataset was separated according to solar cycle (SC)

During geomagnetic storms rapid magnetic variations cause large, sharp enhancements of the magnetic and geoelectric field at mid-latitudes. These present a potential hazard to grounded technology such as high voltage transformers, pipelines and railway systems. Spatiotemporal quantification can provide insight into the magnitude and configuration of their potential hazard. We use the Haar wavelet transform

Space radiation is one of the main concerns in planning long-term human space missions. There are two main types of hazardous radiation: solar energetic particles (SEP) and galactic cosmic rays (GCR). The intensity and evolution of both depends on solar activity. GCR activity is most enhanced during solar minimum and lowest during solar maximum. The reduction of GCRs is alagging behind solar activity

In our previous study (Moon et al., 2020, https://doi.org/10.3938/jkps.77.1265), we developed a long short-term memory (LSTM) deep-learning model for geomagnetic quiet days (LSTM-quiet) to perform effective long-term predictions for the regional ionosphere. However, their model could not predict geomagnetic storm days effectively at all. This study developed an LSTM model suitable for geomagnetic storms

No abstract is available for this article.

Geomagnetically induced currents (GIC) are a phenomenon well known for its negative effects on the operations of power systems. To efficiently mitigate them requires different types of power system modeling, from GIC to alternating current harmonic generation, to three-dimensional finite element models of transformers. GIC are initiated by variations of the geomagnetic field in the presence of the

No abstract is available for this article.

Prediction of geomagnetically induced currents (GICs) plays a critical role in the gestalt of space weather forecasting and risk assessment, giving power companies time to enact mitigation strategies that could avoid a catastrophic collapse of the power grid caused by, for example, the impact of an Earth-directed coronal mass ejection. Sun-to-mud prediction of the surface magnetic field (and/or its

The High Accuracy Satellite Drag Model (HASDM) is the operational thermospheric density model used by the US Space Force Combined Space Operations Center. By using real-time data assimilation, HASDM can provide density estimates with increased accuracy over other empirical models. With historical HASDM density data being released publicly for the first time, we can analyze the data to compare dominant

Reconstruction and prediction of the state of the near-Earth space environment is important for anomaly analysis, development of empirical models and understanding of physical processes. Accurate reanalysis or predictions that account for uncertainties in the associated model and the observations, can be obtained by means of data assimilation. The ensemble Kalman filter (EnKF) is one of the most promising

Geomagnetically induced currents (GICs) at middle latitudes have received increased attention after reported power-grid disruptions due to geomagnetic disturbances. However, quantifying the risk to the electric power grid at middle latitudes is difficult without understanding how the GIC sensors respond to geomagnetic activity on a daily basis. Therefore, in this study the question “Do measured GICs

Monitoring the Earth's radiation belt by Low-Earth-Orbit (LEO) satellites has a long history and complemented observations near the high-altitude equatorial plane. However, most of the previous LEO missions suffered from limitations in energy resolution, energy range, L-shell coverage, or the mission lifetime, which leave room for further improvement in this topic. For <80 keV electrons, the slot-region

The aurora is a readily visible phenomenon of interest to many members of the public. However, the aurora and associated phenomena can also significantly impact communications, ground-based infrastructure, and high-altitude radiation exposure. Forecasting the location of the auroral oval is therefore a key component of space weather forecast operations. A version of the OVATION-Prime 2013 auroral precipitation

The present study investigates the ionospheric F-layer scintillation responses in the American sector (90°W–0°, ±50° dip latitude) during the Northern Hemisphere winter sudden stratospheric warming events of 2007–2008, 2008–2009, 2009–2010, and 2012–2013. The scintillation data used in this work are obtained from the radio occultation observations of the Constellation Observing System for Meteorology

Correction of meteorological effects on muon component of secondary cosmic rays significantly extends the usability of muon monitors. We propose a new data driven empirical method for correction of meteorological effects on muon component of secondary cosmic rays, based on multivariate analysis. Several multivariate algorithms implemented in Toolkit for Multivariate Data Analysis with ROOT framework

Ground level enhancements (GLEs) are space weather events that pose a potential hazard to the aviation environment through single event effects in avionics and increased dose to passengers and crew. The existing ground level neutron monitoring network provides continuous and well-characterized measurements of the radiation environment. However, there are only a few dozen active stations worldwide,

Permanent monitoring and real-time indexing of the geomagnetic activity is of utmost importance for space weather services. In particular, providing a continuous and reliable local magnetic activity nowcast is of increasing importance as it can be used to generate alerts for various users, for instance for GNSS-based applications or to protect electric power grids. This study presents a novel nowcast

Knowledge of the ambient solar wind is important for accurate space-weather forecasting. A simple-but-effective method of forecasting near-Earth solar-wind speed is “corotation”, wherein solar-wind structure is assumed to be fixed in the reference frame rotating with the Sun. Under this approximation, observations at a source spacecraft can be rotated to a target location, such as Earth. Forecast accuracy

As space science in the commercial sector grows, new opportunities emerge for data availability and collaboration between the public and private sectors.

No abstract is available for this article.

The effects of solar radiation storms at Earth are felt across a number of technology-based industries. Energetic particles present during these storms impact electrical components on spacecraft, disrupt high frequency radio communications, and pose a radiation risk for passengers and crew on polar flight routes, as well as for astronauts. An essential aspect of space weather forecasting is therefore

The midlatitude ionospheric trough (MIT) is a well-known feature in the topside ionosphere. Previous MIT related studies mainly focused on the MIT structure itself, while few studies focused on irregularities inside the MIT region. In this study, we provided for the first time the magnetic latitude and magnetic local time distribution of irregularities within the MIT, by using the Swarm in situ plasma

The solar X-ray irradiance is significantly heightened during the course of a solar flare, which can cause radio blackouts due to ionization of the atoms in the ionosphere. As the duration of a solar flare is not related to the size of that flare, it is not directly clear how long those blackouts can persist. Using a random forest regression model trained on data taken from X-ray light curves, we have

Space weather instrumentation on board the National Oceanic and Atmospheric Administration's (NOAA's) newest Geostationary Operational Environmental Satellite (GOES)-R series includes the Solar and Galactic Proton Sensor (SGPS), which has been collecting data since 8 January 2017. SGPS supports real-time alerts of solar energetic particle (SEP) events at the NOAA Space Weather Prediction Center (SWPC)

The temporal change in height of a specific electron density can be used as a proxy for vertical plasma drift (PVPD) at the magnetic equator. The use of PVPDs as a predictor of low-latitude ionospheric scintillation during the subsequent evening has previously been shown to have forecasting skill when using ionosonde data. The implementation of this approach using a physics-based model is proposed

At present, the most reliable information for inferring storm-time ground electric fields along electrical transmission lines comes from coarsely sampled, national-scale magnetotelluric (MT) data sets, such as that provided by the EarthScope USArray program. An underlying assumption in the use of such data is that they adequately sample the spatial heterogeneity of the surface relationship between

The present study confirms the validity of previously derived relations between the polar cap (PC) indices and the ASY-H and the Dst and SYM-H ring current indices when used in real-time applications. PC indices are here derived in simulated real-time (SRT) versions by using past data only from −40 days up to current time in the construction of the quiet reference levels (QDCs) for the magnetic data

We examine how Sudden Commencements (SCs) and Storm Sudden Commencements (SSCs) influence the occurrence of high rates of change of the magnetic field (R) as a function of geomagnetic latitude. These rapid, high amplitude variations in the ground-level geomagnetic field pose a significant risk to ground infrastructure, such as power networks, as the drivers of geomagnetically induced currents. We find

As more and more high-technical systems are exposed to the space environment, extreme space weather becomes a great threat to human society. In the solar system, space weather is influenced by the solar wind, such that reliable prediction of solar wind conditions in the near-Earth environment effectively reduces the impact of space weather on human society. Solar wind speed prediction is improved by

Data Assimilation (DA) has enabled huge improvements in the skill of terrestrial operational weather forecasting. In this study, we use a variational DA scheme with a computationally efficient solar wind model and in situ observations from STEREO-A, STEREO-B and ACE. This scheme enables solar-wind observations far from the Sun, such as at 1 AU, to update and improve the inner boundary conditions of

No abstract is available for this article.

Variability in near-Earth solar wind conditions gives rise to space weather, which can have adverse effects on space- and ground-based technologies. Enhanced and sustained solar wind coupling with the Earth's magnetosphere can lead to a geomagnetic storm. The resulting effects can interfere with power transmission grids, potentially affecting today's technology-centered society to great cost. It is

In this research, we present data-driven forecasting of ionospheric total electron content (TEC) using the Long-Short Term Memory (LSTM) deep recurrent neural network method. The random forest machine learning method was used to perform a regression analysis and estimate the variable importance of the input parameters. The input data are obtained from satellite and ground based measurements characterizing

Deep signal fading due to ionospheric scintillation severely impacts global navigation satellite system (GNSS)-based applications. GNSS receivers run the risk of signal loss under deep fading, which directly leads to a significant decrease in navigation availability. The impact of scintillation on GNSS-based applications can be mitigated via dual-frequency signals which provide a backup channel. However

Solar wind parameters, the solar radio flux index (F10.7), the Sun's declination and the SuperMAG Electrojet index are used to construct a Bayesian inference-based empirical model for scintillation indices (S4 and σΦ) at high latitudes. For the present study, measurements from three Global Positioning System (GPS) L1 receivers located in the auroral zone, the cusp and in the polar cap are selected

While low and high-latitude ionospheric scintillation have been extensively reported, significantly less information is available about the properties of and conditions leading to mid-latitude scintillations. Here, we report and discuss scintillation observations made in the Southern United States (UT Dallas, 32.99°N, 96.76°W, 43.2°N dip latitude) on June 1st, 2013. The measurements were made by a

The Norwegian Mapping Authority operates a network real time kinematic (RTK) system called CPOS, a positioning service providing centimeter level accuracy aimed at commercial users, for example, in civil engineering, excavation, and surveying. CPOS is based on multiple Global Navigation Satellite Systems (multi-GNSS) in addition to base stations to provide correction data. CPOS position accuracy is

A communication deficit exists between the space weather research and forecast communities in the research-to-operations-to-research (R2O2R) pipeline. No formal, citable space exists for forecasters to communicate needs and lessons learned to the research community (O2R). This deficit was termed the “valleys of death and lost opportunities” (NRC, 2003, https://doi.org/10.17226/10658) and has resulted

Accurate predictions of the properties of interplanetary coronal mass ejection (ICME)-driven disturbances are a key objective for space weather forecasts. The ICME's time of arrival (ToA) at Earth is an important parameter, and one that is amenable to a variety of modeling approaches. Previous studies suggest that the best models can predict the arrival time to within an absolute uncertainty of 10–15 h

The paper investigates the strengthening of magnetospheric activity related to geosynchronous magnetopause crossings (GMCs). We make a list of GMC events using the empirical magnetopause model (Lin et al., 2010, https://doi.org/10.1029/2009ja014235) and hourly averaged OMNI data and find which solar wind and magnetospheric conditions accompany and follow the GMCs. The GMCs are mostly caused by the

Satellite-atmosphere interactions cause large uncertainties in low-Earth orbit determination and prediction. Thus, knowledge of and the ability to predict the space environment, most notably thermospheric mass density, are essential for operating satellites in this domain. Recent progress has been made toward supplanting the existing empirical, operational methods with physics-based data-assimilative

Geodetic very long baseline interferometry (VLBI) observations are carried out, with the legacy system, using two well-separated frequency bands in order to determine first-order ionospheric delay corrections corresponding to the combined effect of total electron content (TEC) at two stations forming a baseline. On the other hand, it is possible to obtain the vertical TEC (VTEC) above the VLBI antennas

Geomagnetic indices quantify the disturbance caused by the solar activity on a planetary scale or in particular regions of the Earth. Among them, the SYM-H and ASY-H indices represent the (longitudinally) symmetric and asymmetric geomagnetic disturbance of the horizontal component of the magnetic field at midlatitude with a 1-min resolution. Their resolution, along with their relation to the solar

We advance the modeling capability of electron particle precipitation from the magnetosphere to the ionosphere through a new database and use of machine learning (ML) tools to gain utility from those data. We have compiled, curated, analyzed, and made available a new and more capable database of particle precipitation data that includes 51 satellite years of Defense Meteorological Satellite Program

Accurate measurements of trapped energetic electron fluxes are of major importance for the studies of the complex nature of radiation belts and the characterization of space radiation environment. The harmonization of measurements between different instruments increases the accuracy of scientific studies and the reliability of data-driven models that treat the specification of space radiation environment

We propose a method, based on Neural Networks, that detects the nonlinear robust interplanetary solar wind variables, with varying delays, driving the coupled behavior of three geomagnetic indices (Dst, AL, and AU). As opposed to minimizing a prediction error, the method is based on degrading the prediction by distorting the inputs of the trained Neural Networks in order to highlight the most sensible

Space weather forecasts are generally made for events with an arbitrary size threshold imposed on an event statistical size distribution which is likely described by a power law. This is the case for solar energetic (E > 10 MeV) particle (SEP) events, which have a differential power law exponent of γ = 1.2. Event forecasts are usually evaluated by skill scores using a contingency table that matches

The Feature Tracking of Aurora (FTA) model was constructed using 1.5 years of Polar Ultraviolet Imager data and is based on tracking a cumulative energy grid in 96 magnetic local time (MLT) sectors. The equatorward boundary, poleward boundary, and 19 cumulative energy bins are tracked with the energy flux and the latitudinal position. With AE increasing, the equatorward boundary moves to lower latitudes