@proceedings {1014, title = {Multi-Year Climatology of Large-Scale Traveling Ionospheric Disturbances Observed with High Frequency Amateur Radio Receiving Networks Using a Novel Automated Detection Algorithm}, year = {2026}, month = {03/2026}, publisher = {HamSCI}, address = {Newington, CT}, abstract = {We present a fully automated, deterministic technique for detecting and characterizing Large Scale Traveling Ionospheric Disturbances (LSTIDs) using 14 MHz amateur (ham) radio data. The method isolates wave periods between 1{\textendash}5 hours and applies sinusoidal curve fitting to the first-hop skip-distance edge of observed communication ranges, yielding quantitative estimates of LSTID amplitude and period. Data from the Weak Signal Propagation Reporting Network (WSPRNet), the Reverse Beacon Network (RBN), and PSKReporter, which is now merged and available on the CEDAR Madrigal database, were used produce a unified multi-year climatology of LSTID activity over the continental United States (2016{\textendash}2023). Results show clear seasonal patterns: enhanced LSTID occurrence during winter, weaker activity in spring and fall, and modest summer increases. These results are consistent with prior studies and suggest modulation by neutral wind filtering, sudden stratospheric warming (SSW), vertical coupling, and solar activity.}, author = {Diego Sanchez and Mary Lou West and Nathaniel Frissell and Gareth Perry and V. Lynn Harve and Bill Engelke and Nicholas Callahan and Philip Erickso and Erich Becker and Sharon Vadas} } @proceedings {949, title = {Climatology of Large-Scale Traveling Ionospheric Disturbances Observed with 14 MHz Amateur Radio Using a Novel Automated Detection Technique}, year = {2025}, month = {03/2025}, publisher = {HamSCI}, address = {Newark, NJ}, abstract = {

We present a multi-year climatology of Large Scale Traveling Ionospheric Disturbance (LSTID) period oscillations observed using 14 MHz amateur (ham) radio data. Traveling ionospheric disturbances (TIDs) are quasi periodic electron density perturbations in the F region ionosphere that affect radio communications and can help with understanding energy transport throughout the coupled magnetosphere-ionosphere-neutral atmosphere system. These are seen, in daytime, as variations in contact ranges in 14 MHz amateur radio communication reports recorded by automated monitoring systems such as the Weak Signal Propagation Reporting Network (WSPRNet), the Reverse Beacon Network (RBN), and PSKReporter. A new deterministic and fully automated method was developed for identifying and quantifying these disturbances. This technique, which filters for TID wave periods between 1 and 5 hours and curve fits a sinusoidal function to the first hop skip-distance edge of observed communication ranges, provides both TID amplitudes and periods. In this study, we present full year climatologies of LSTID events over the continental United States (CONUS) using RBN, WSPRNet, and PSK observations from 2016- 2021. Results are organized as a function wave period, amplitude, and season. We find that LSTIDs increase in winter and decline during the fall and spring, with slight enhancements in the summer and occasional brief declines in LSTID winter activity. This seasonal pattern shows consistency with previous studies and observations of LSTIDs and medium scale TIDs that suggests this behavior may be associated with neutral wind filtering in the middle atmosphere, sudden stratospheric warming (SSW) events, and multi-step vertical coupling (MSVC) processes. MSVC is a process where gravity waves (GWs) from the lower neutral atmosphere propagate upwards, break, and produce new, higher-order GWs in the thermosphere and TIDs in the ionosphere.

}, author = {Diego Sanchez and Nathaniel Frissell and Mary Lou West and V. Lynn Harvey and Sharon Vadas and Erich Becker and Gareth Perry and William Engelke and Nicholas Callahan and Philip Erickson} } @proceedings {929, title = {HamSCI Solar Eclipse QSO Party (SEQP): Observations and Modeling on Ionospheric Effects}, year = {2025}, month = {03/2025}, publisher = {HamSCI}, address = {Newark, NJ}, abstract = {

This study investigates the ionospheric changes during the solar eclipse of April 2024 using data from the HamSCI Solar Eclipse QSO Party (SEQP). SEQP collected radio communication data reported by ham radio operators and global automated receiving networks (e.g., WSPRNet, the Reverse Beacon Network, and PSKReporter). The datasets include radio communications at multiple frequencies in the high frequency (HF) and very high frequency (VHF) bands. Thousands of ham radio operators across the contiguous United States (CONUS) and around the globe contributed to the observations with unprecedented temporal, spatial, and spectral coverage. SEQP datasets are used to infer ionospheric state before, during, and after the solar eclipse. We use the ham radio datasets along with PHaRLAP raytrace modeling to infer the ionospheric response of the solar eclipse and also evaluate the outputs of the physics-based model SAMI3 for the eclipse ionosphere. Our findings suggest that the solar eclipse increased the range of radio communications at lower HF band (3.5, 7, 10 MHz), but decreased the longer range communications at higher HF band (21, 24, 28 MHz). Ham radio datasets from stations continually operated during the eclipse show an earlier opening of radio links between the US and Europe on the eclipse day. We are conducting modeling studies to understand the causes of changes in ham radio observations and to examine the potential combined effect of the sunset terminator and eclipse shadow during the later phase of the eclipse.

}, author = {Kuldeep Pandey and Gareth Perry and Nathaniel Frissell and Travis Atkinson and William Engelke and Joseph Huba and Mary Lou West and Philip Gladstone and Cameron Cushing and McKenzie Denton and Edward Efchak and Gary Mikitin and H. Ward Silver} } @proceedings {957, title = {How Do We Put a HamSCI Personal Space Weather Station in Antarctica?}, year = {2025}, month = {03/2025}, publisher = {HamSCI}, address = {Newark, NJ}, abstract = {

We present initial ideas on how to place a HamSCI Personal Space Weather Station at United States Antarctic Research Stations.

}, author = {Rebecca Potter and Nina Tormann and Christine Zakzewski and Majid Mokhtari and Nathaniel Frissell and Ken Martin and Jermey McLynch and Hyomin Kim and Gareth Perry and David McGaw and James LaBelle and Tedi Godfrey and Michael Hartje and Gwyn Griffiths and Rob Robinett and Paul Elliott} } @proceedings {975, title = {Incorporating HamSCI Project into a College Physics Course: A Progress Report}, year = {2025}, month = {03/2025}, publisher = {HamSCI}, address = {Newark, NJ}, abstract = {

We report on citizen science activities in a physics course and Space Force ROTC training designed to engage undergraduate students and cadets in the HamSCI Personal Space Weather Station (PSWS) project. The New Jersey Institute of Technology (NJIT) Physics Department offers a senior-level lab course, "Advanced Physics Lab," where students are expected to gain hands-on experience with experimental techniques, instrumentation, theoretical and applied electronics, solid-state electronic devices, and experiments in modern physics by performing quantitative measurements of fundamental physical parameters. In this lab, students work in a largely unstructured environment, where they are provided with equipment and related manuals to conduct experiments with minimal instructor supervision. Traditionally, students have followed preset lab setups, guided by the manuals that accompany the equipment. While this approach helps students relate lab results to established physics theories and principles, its impact has been limited due to a lack of "hands-on" experience and real-world application demonstrations. The HamSCI PSWS project provides an excellent opportunity to address this gap. Through the project, students build and test scientific instruments, using them for investigations that engage them directly in scientific inquiry. This paper presents an evaluation of the impact of this undergraduate class activity on future workforce development, utilizing HamSCI resources.

}, author = {Hyomin Kim and Jeremy McLynch and Joseph Visone and Dominick Santelli and Sergio Santelli and Gareth Perry and Nathaniel Frissell and Gary Mikitin and John Gibbons and David Witten} } @proceedings {936, title = {Ionospheric Variability{\textquoteright}s Impact on HF Propagation: Insights from Grape V1 Doppler Residuals and PHaRLAP Ray Tracing}, year = {2025}, month = {03/2025}, publisher = {HamSCI}, address = {Newark, NJ}, abstract = {

This study investigates the impact of ionospheric variability on HF (3-30 MHz) skywave propagation, a critical aspect of long-range radio communication. Using a dedicated HamSCI Grape V1 low-IF receiver (K2MFF) at NJIT, we analyze long-term Doppler residual measurements of the 10 MHz WWV signal from Fort Collins, CO. Our observations reveal a strong correlation between stable daytime propagation and a Cauchy distribution of Doppler residuals, while sporadic nighttime conditions align more with a combination of exponential power and log-normal statistics. This pattern is consistent across our dataset, barring dates of atypical solar irradiance on the ionosphere, such as during high-class solar flares and solar eclipses. We compare these findings with PHaRLAP ray-tracing simulations using an IRI ionosphere model, allowing us to visualize the signal{\textquoteright}s ray path and pinpoint the ionospheric altitudes (100-400 km) responsible for observed features. Raytracing results attribute daytime signal stability to a superposition of multi-hop modes, while nighttime oscillations linked to TIDs are measurable due to 1-hop dominance. By examining diurnal variations in Doppler residuals, this work provides amateur radio operators with a better understanding of ionospheric dynamics and their impact on HF communication, ultimately contributing to improved prediction of propagation conditions and more effective use of the HF spectrum. Additionally, this work provides a foundation for interpreting real-time propagation data and understanding the effects of solar activity and ionospheric variations on signal quality and reliability for amateur radio communication.

}, author = {Sabastian Fernandes and Gareth Perry and Tiago Trigo and Nathaniel Frissell and John Gibbons} } @proceedings {862, title = {Incorporating HamSCI Project into a College Physics Course}, year = {2024}, month = {03/2024}, publisher = {HamSCI}, address = {Cleveland, OH}, abstract = {

We report citizen science activity in a physics course to engage undergraduate students in a HamSCI Personal Space Weather Station (PSWS) project. The New Jersey Institute of Technology (NJIT) Physics Department has been offering a senior-level lab course, "Advanced Physics Lab" in which the students are expected to gain experience with experimental techniques, instrumentation, theoretical and applied electronics, solid state electronic devices, experiments in modern physics by performing quantitative measurements of fundamental physical parameters. Students perform lab experiments in a mostly unstructured setting, in which students are given the equipment and related manuals and perform experiments with very minimal instructor{\textquoteright}s supervision. Historically, the students have been given a pre-set lab equipment by following the manuals accompanied by the equipment. While this may be suitable for providing an opportunity for the students to relate the results in the lab with the known physics theories/principles, the impact to the students is limited as there is still insufficient "hands-on" components and demonstration of real-world applications. The HamSCI PSWS project is a good example in which students build and test science instruments and use them for scientific investigations to address this issue. We present undergraduate class activity and evaluate their impact on future workforce training utilizing the HamSCI resources.\ 

}, author = {Hyomin Kim and Lindsay Goodwin and Gareth Perry and Nathaniel A. Frissell and Gary Mikitin} } @proceedings {479, title = {e-POP RRI observations of the April 24, 2020 ARRL Frequency Measuring Test}, year = {2021}, month = {03/2021}, publisher = {HamSCI}, address = {Scranton, PA (Virtual)}, abstract = {

One of the science objectives of the Radio Receiver Instrument (RRI) on the CAScade, Smallsat, and Ionospheric Polar Explorer/enhanced Polar Outflow Probe (CASSIOPE/e-POP) satellite is to study ionospheric influences on high frequency (HF) radio wave from low Earth orbit. RRI is made-up of 4, 3-m monopoles which can be electronically arranged into a crossed-dipole configuration.\  On April 24, 2020, RRI tuned to measure the ARRL frequency measuring test (FMT) on 40 m, and successfully recorded part of the {\textquotedblleft}call up{\textquotedblright} and all of the {\textquotedblleft}key down{\textquotedblright} segments of the test.\  The FMT provides a unique chance to study the effects of the ionospheric plasma on stable and reliable radio signals at frequencies that are close to the ionosphere{\textquoteright}s critical frequency, a frequency regime in which the influence of the ionospheric plasma on radio wave propagation conditions is most pronounced.\  In this presentation, we give preliminary results of our analysis of RRI{\textquoteright}s FMT measurements which include an examination of the FMT{\textquoteright}s Doppler characteristics, and the identification tell-tale signatures of ionospheric effects on the transmitted signal such as Faraday rotation and propagation mode delay.

}, url = {https://hamsci2021-uscranton.ipostersessions.com/?s=34-2B-1B-32-C8-FC-4A-0B-5B-51-B9-1D-10-4E-F2-7F}, author = {Brian O{\textquoteright}Donnell and Gareth Perry} } @conference {550, title = {HamSCI Campaign Co-Design (Panel Discussion)}, booktitle = {HamSCI Workshop 2021}, year = {2021}, month = {03/2021}, publisher = {HamSCI}, organization = {HamSCI}, address = {Virtual}, author = {Kristina V. Collins and Nathaniel A. Frissell and Philip J. Erickson and Laura Brandt and Elizabeth MacDonald and Michael Black and Gareth Perry} } @conference {539, title = {HF Doppler Observations of Traveling Ionospheric Disturbances in a WWV Signal Received with a Network of Low-Cost HamSCI Personal Space Weather Stations}, booktitle = {NSF CEDAR (Coupling, Energetics, and Dynamics of Atmospheric Regions)}, year = {2021}, month = {06/2021}, publisher = {CEDAR}, organization = {CEDAR}, address = {Virtual}, abstract = {

Traveling Ionospheric Disturbances (TIDs) are quasi-periodic variations in ionospheric electron density that are often associated with atmospheric gravity waves. TIDs cause amplitude and frequency variations in high frequency (HF, 3-30 MHz) refracted radio waves. We present observations of TIDs made with a network of Ham Radio Science Citizen Investigation (HamSCI) Low-Cost Personal Space Weather Stations (PSWS) with nodes located in Pennsylvania, New Jersey, and Ohio. The TIDs were detected in the Doppler shifted carrier of the received signal from the 10 MHz WWV frequency and time standard station in Fort Collins, CO. Using a lagged cross correlation analysis, we demonstrate a method for determining TID wavelength, direction, and period using the collected WWV HF Doppler shifted data.

}, author = {Veronica I. Romanek and Nathaniel A. Frissell and Dev Joshi and William Liles and Clair Trop and Kristina Collins and Gareth Perry} } @conference {399, title = {Novel methods for characterizing ionospheric irregularities in the high-latitude ionosphere (ePoster)}, booktitle = {HamSCI Workshop 2020}, year = {2020}, month = {03/2020}, publisher = {HamSCI}, organization = {HamSCI}, address = {Scranton, PA}, abstract = {

Plasma structuring in the high-latitude ionosphere impacts over-the-horizon radio communication and global navigation systems, and is an important space weather effect. Therefore, characterizing the formation and evolution of these structures is critically important. It is useful to create {\textquoteleft}{\textquoteleft}irregularity spectra", which quantify the sizes of plasma structures in the high-latitude ionosphere.\ \ The shape of the spectra (and other characteristics) can provide insight into the source of the irregularities. From this information it is then possible to forecast the occurrence of irregularities and predict their impact on radio wave propagation and communications. We are able to compute irregularity spectra by leveraging the phased array design of several incoherent scatter radars (ISRs), and using some unique properties of the F-region plasma at high-latitudes.\ \ In this presentation we will describe how we develop and apply a novel technique for ISR measurements to resolve high-latitude ionospheric irregularity spectra at a finer resolution than has been previously possible with ground-based instruments. We will motivate the newly developed ISR technique, describe its methodology, and provide some first results demonstrating its effectiveness. This technique will enable future studies that will directly link high-latitude ionospheric plasma structure drivers to their impact on radio wave communications.

}, author = {Lindsay V. Goodwin and Gareth Perry} } @conference {51, title = {e-POP Radio Science Using Amateur Radio Transmissions}, booktitle = {Fall AGU - Poster Presentation}, year = {2015}, month = {12/2015}, publisher = {American Geophysical Union}, organization = {American Geophysical Union}, address = {San Francisco, CA}, abstract = {

A major component of the enhanced Polar Outflow Probe (e-POP) Radio Receiver Instrument (RRI) mission is to utilize artificially generated radio emissions to study High Frequency (HF) radio wave propagation in the ionosphere. In the North American and European sectors, communications between amateur radio operators are a persistent and abundant source source of HF transmissions. We present the results of HF radio wave propagation experiments using amateur radio transmissions as an HF source for e-POP RRI. We detail how a distributed and autonomously operated amateur radio network can be leveraged to study HF radio wave propagation as well as the structuring and dynamics of the ionosphere over a large geographic region. In one case, the sudden disappearance of nearly two-dozen amateur radio HF sources located in the midwestern United States was used to detect a enhancement in foF2 in that same region. We compare our results to those from other more conventional radio instruments and models of the ionosphere to demonstrate the scientific merit of incorporating amateur radio networks for radio science at HF.

}, author = {Nathaniel A. Frissell and Gareth Perry and Ethan S. Miller and Alex Shovkoplyas and Magdalina Moses and H. James and Andrew Yau} }