Explanipedia

Reply on RC2 Open

Daniel J. Emmons · 2025

Reply on RC1 Open

Daniel J. Emmons · 2025

A comparison of modeled daytime E-regions from E-PROBED and PyIRI with ionosonde observations Open

Daniel J. Emmons, Cornelius Csar Jude H. Salinas, Dong L. Wu, Nimalan Swarnalingam, E. V. Dao , et al. · 2025

While the F-region is the primary focus of many ionospheric models because it contains the peak electron density, the E-region is an important region for ionospheric conductivities and high-frequency radio propagation. This study analyzes …

Magnetic Field Variability as a Consistent Predictor of Solar Flares Open

Kara Kniezewski, Emily I. Mason, Daniel J. Emmons, Kyle E. Fitch, Seth H. Garland · 2025

Solar flares are intense bursts of electromagnetic radiation that occur due to a rapid destabilization and reconnection of the magnetic field. While preflare signatures and trends have been investigated from magnetic observations prior to …

Magnetic Field Variability as a Consistent Predictor of Solar Flares Open

Kara Kniezewski, Emily I. Mason, Daniel J. Emmons, Kyle E. Fitch, Seth H. Garland · 2025

Solar flares are intense bursts of electromagnetic radiation, which occur due to a rapid destabilization and reconnection of the magnetic field. While pre-flare signatures and trends have been investigated from magnetic observations prior …

Global Sporadic‐E Prediction and Climatology Using Deep Learning Open

J. Austin Ellis, Daniel J. Emmons, M. B. Cohen · 2025

Sporadic‐E is an ionospheric phenomenon defined by strong layers of plasma which may interfere with radio wave propagation. In this work, we develop deep learning models to improve the understanding of , including the presence, intensity a…

Simultaneous observations of irregular sporadic E structures using the LWA and a DPS4D Open

K. S. Obenberger, Caz M. Taylor, Jonah J. Colman, E. V. Dao, Jayce Dowell , et al. · 2025

Multi-instrument studies have recently shed new light on the morphology of sporadic E, especially intense sporadic E. Here we present simultaneous observations of dense sporadic E ( ) structures using the Long Wavelength Array (LWA) radio…

Analyzing LF/VLF lightning waveforms to estimate D-region electron density profiles Open

William Robert Smith, E. H. Lay, Kyle E. Fitch, Daniel J. Emmons · 2025

Corrigendum: Global empirical model of sporadic-E occurrence rates Open

Eli V. Parsch, Anthony L. Franz, E. V. Dao, Dong L. Wu, Nimalan Swarnalingam , et al. · 2025

HF Radar Observations and Modeling of the Impact of the 8 April 2024 Total Solar Eclipse on the Ionosphere‐Thermosphere System Open

B. Kunduri, J. B. H. Baker, J. M. Ruohoniemi, E. G. Thomas, J. D. Huba , et al. · 2024

The path of totality of the 8 April 2024 solar eclipse traversed the fields‐of‐view of four US SuperDARN radars. This rare scenario provided an excellent opportunity to monitor the large‐scale ionospheric response to the eclipse. In this s…

Global Empirical Model of Sporadic-E Occurrence Rates Open

Eli V. Parsch, Anthony L. Franz, E. V. Dao, Dong L. Wu, Nimalan Swarnalingam , et al. · 2024

Intense ionization enhancements in the Earth’s ionosphere, known as sporadic-E ( ), can degrade and severely disrupt the propagation of radio signals. Although many previous studies have analyzed the characteristics and morphologies of sp…

Development of the Ionospheric E‐Region Prompt Radio Occultation Based Electron Density (E‐PROBED) Model Open

Cornelius Csar Jude H. Salinas, Dong L. Wu, Nimalan Swarnalingam, Daniel J. Emmons, Liying Qian · 2024

This work reports the development of the first version of the E‐region Prompt Radio Occultation Based Electron Density (E‐PROBED) Model. This is an empirical model of E‐region electron density (Ne) between 90 and 120 km developed using rad…

Analysis of modeled 3D solar magnetic field during 30 X/M-class solar flares Open

Seth H. Garland, Vasyl Yurchyshyn, Robert Loper, Benjamin F. Akers, Daniel J. Emmons · 2024

Using non-linear force free field (NLFFF) extrapolation, 3D magnetic fields were modeled from the 12-min cadence Solar Dynamics Observatory Helioseismic and Magnetic Imager (HMI) photospheric vector magnetograms, spanning a time period of …

Editorial: Observations and simulations of layering phenomena in the middle/upper atmosphere and ionosphere Open

Bingkun Yu, Xuguang Cai, Daniel J. Emmons, Chong Wang, Jianfei Wu · 2024

EDITORIAL article Front. Astron. Space Sci., 12 January 2024Sec. Space Physics Volume 10 - 2023 | https://doi.org/10.3389/fspas.2023.1361434

Detection and Classification of Sporadic E Using Convolutional Neural Networks Open

J. Austin Ellis, Daniel J. Emmons, M. B. Cohen · 2024

In this work, convolutional neural networks (CNN) are developed to detect and characterize sporadic E ( E s ), demonstrating an improvement over current methods. This includes a binary classification model to determine if E s is present, f…

Improved models for estimating sporadic-E intensity from GNSS radio occultation measurements Open

Daniel J. Emmons, Dong L. Wu, Nimalan Swarnalingam, A. Ali, Joseph A. Ellis , et al. · 2023

Several models for estimating sporadic-E intensity from Global Navigation Satellite System (GNSS) radio occultation (RO) observation have previously been developed using a single perturbation or intensity parameter, such as phase-based tot…

Impacts of Kelvin-Helmholtz billow formation on GNSS radio occultation measurements of sporadic-E Open

Andrew J. Knisely, Daniel J. Emmons · 2023

Global Navigation Satellite System (GNSS) Radio Occultation (RO) has shown great promise for monitoring sporadic-E layers. However, extracting sporadic-E information from RO signals remains a difficult task due to the many unknown paramete…

Comparison of a Bottom-Up GNSS Radio Occultation Method to Measure D- and E-Region Electron Densities with Ionosondes and FIRI Open

Dylan J. Shaver, Dong L. Wu, Nimalan Swarnalingam, Anthony L. Franz, E. V. Dao , et al. · 2023

High-frequency skywave propagation can be heavily impacted by D- and E-region dynamics requiring accurate global measurements to optimize performance. A standard measurement technique is to use ionosondes, but they are unable to measure be…

Global Ionospheric Electron Density from GNSS-POD Limb Measurements Open

Dong L. Wu, Nimalan Swarnalingam, Cornelius Csar Jude H. Salinas, Daniel J. Emmons, Tyler C. Summers · 2023

GNSS-LEO radio links from Precise Orbital Determination (POD) and Radio Occultation (RO) antennas have been used increasingly in studying and monitoring the global ionospheric electron density (Nₑ). In this study we developed an optimal es…

Optimal Estimation Inversion of Ionospheric Electron Density from GNSS-POD Limb Measurements: Part II-Validation and Comparison Using NmF2 and hmF2 Open

Nimalan Swarnalingam, Dong L. Wu, Daniel J. Emmons, Robert S. Gardiner‐Garden · 2023

A growing number of SmallSat/CubeSat constellations with high-rate (50–100 Hz) global navigation satellite system radio occultations (GNSS-RO) as well as low-rate (1 Hz) precise orbit determination (GNSS-POD) limb-viewing capabilities prov…

Optimal Estimation Inversion of Ionospheric Electron Density from GNSS-POD Limb Measurements: Part I-Algorithm and Morphology Open

Dong L. Wu, Nimalan Swarnalingam, Cornelius Csar Jude H. Salinas, Daniel J. Emmons, Tyler C. Summers , et al. · 2023

GNSS-LEO radio links from Precise Orbital Determination (POD) and Radio Occultation (RO) antennas have been used increasingly in characterizing the global 3D distribution and variability of ionospheric electron density (Ne). In this study,…

Evolution of coronal magnetic field parameters during X5.4 solar flare Open

Seth H. Garland, Vasyl Yurchyshyn, Robert Loper, Benjamin F. Akers, Daniel J. Emmons · 2023

The coronal magnetic field over NOAA Active Region 11,429 during a X5.4 solar flare on 7 March 2012 is modeled using optimization based Non-Linear Force-Free Field extrapolation. Specifically, 3D magnetic fields were modeled for 11 timeste…

Characterization of Intense Sporadic-E Through the Combination of Ionosonde Data and Amateur Radio Observations Open

Kenneth Edward Neubeck, Daniel J. Emmons · 2023

A Statistical Analysis of Sporadic-E Characteristics Associated with GNSS Radio Occultation Phase and Amplitude Scintillations Open

Daniel J. Emmons, Dong L. Wu, Nimalan Swarnalingam · 2022

Statistical GNSS-RO measurements of phase and amplitude scintillation are analyzed at the mid-latitudes in the local summer for a 100 km altitude. These conditions are known to contain frequent sporadic-E, and the S4-σϕ trends provide insi…

Global Sporadic‐E Occurrence Rate Climatology Using GPS Radio Occultation and Ionosonde Data Open

Travis J. Hodos, O. Nava, E. V. Dao, Daniel J. Emmons · 2022

An updated global climatology of blanketing sporadic E (E s ) is developed from a combined data set of Global Positioning System (GPS) radio occultation (RO) and ground‐based ionosonde soundings over the period of September 2006–January 20…

Long-distance propagation of 162 MHz shipping information links associated with sporadic E Open