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Large-scale observations of a subauroral polarization stream by midlatitude SuperDARN radars: Instantaneous longitudinal velocity variations
Clausen, L. B. N., J. B. H. Baker, J. M. Ruohoniemi, R. A. Greenwald, E. G. Thomas, S. G. Shepherd, E. R. Talaat, W. A. Bristow, Y. Zheng, A. J. Coster, and S. Sazykini (2012), Large-scale observations of a subauroral polarization stream by midlatitude SuperDARN radars: Instantaneous longitudinal velocity variations, J. Geophys. Res., 117, A05306, doi:10.1029/2011JA017232.
An examination of interhemispheric conjugacy in a sub-auroral polarization stream
Kunduri, B. S. R., J. B. H. Baker, J. M. Ruohoniemi, L. B. N. Clausen, A. Grocott, E. G. Thomas, M. P. Freeman, and E. R. Talaat (2012), An examination of interhemispheric conjugacy in a sub-auroral polarization stream, J. Geophys. Res., 117, A08225, doi:10.1029/2012JA017784.
Direct observations of the role of convection electric field in the formation of a polar tongue of ionization from storm enhanced density
Thomas, E. G., J. B. H. Baker, J. M. Ruohoniemi, L. B. N. Clausen, A. J. Coster, J. C. Foster, and P. J. Erickson (2013), Direct observations of the role of convection electric field in the formation of a polar tongue of ionization from storm enhanced density, J. Geophys. Res. Space Physics, 118, 1180-1189, doi:10.1002/jgra.50116.
Direct Observations of the Evolution of Polar Cap Ionization Patches
Zhang, Q.-H., B.-C. Zhang, M. Lockwood, H.-Q. Hu, J. Moen, J. M. Ruohoniemi, E. G. Thomas, S.-R. Zhang, H.-G. Yang, R.-Y. Liu, K. A. McWilliams, and J. B. H. Baker (2013), Direct Observations of the Evolution of Polar Cap Ionization Patches, Science, 339, 1597-1600, doi:10.1126/science.1231487.
GPS phase scintillation and proxy index at high latitudes during a moderate geomagnetic storm
Prikryl, P., R. Ghoddousi-Fard, B. S. R. Kunduri, E. G. Thomas, A. J. Coster, P. T. Jayachandran, E. Spanswick, and D. W. Danskin (2013), GPS phase scintillation and proxy index at high latitudes during a moderate geomagnetic storm, Ann. Geophys., 31, 805-816, doi:10.5194/angeo-31-805-2013.
Multi-instrument observations of SED during 24-25 October 2011 storm: Implications for SED formation processes
Zou, S., A. J. Ridley, M. B. Moldwin, M. J. Nicolls, A. J. Coster, E. G. Thomas, and J. M. Ruohoniemi (2013), Multi-instrument observations of SED during 24-25 October 2011 storm: Implications for SED formation processes, J. Geophys. Res. Space Physics, 118, 7798-7809, doi:10.1002/2013JA018860.
On the generation/decay of the storm-enhanced density plumes: Role of the convection flow and field-aligned ion flow
Zou, S., M. B. Moldwin, A. J. Ridley, M. J. Nicolls, A. J. Coster, E. G. Thomas, and J. M. Ruohoniemi (2014), On the generation/decay of the storm-enhanced density plumes: Role of the convection flow and field-aligned ion flow, J. Geophys. Res. Space Physics, 119, 8543-8559, doi:10.1002/2014JA020408.
GPS phase scintillation at high latitudes during geomagnetic storms of 7-17 March 2012 - Part 1: The North American sector
Prikryl, P., R. Ghoddousi-Fard, E. G. Thomas, J. M. Ruohoniemi, S. G. Shepherd, P. T. Jayachandran, D. W. Danskin, E. Spanswick, Y. Zhang, Y. Jiao, and Y. T. Morton (2015), GPS phase scintillation at high latitudes during geomagnetic storms of 7-17 March 2012 - Part 1: The North American sector, Ann. Geophys., 33, 636-656, doi:10.5194/angeo-33-637-2015.
GPS phase scintillation at high latitudes during geomagnetic storms of 7-17 March 2012 - Part 2: Interhemispheric comparison
Prikryl, P., R. Ghoddousi-Fard, L. Spogli, C. N. Mitchell, G. Li, B. Ning, P. J. Cilliers, V. Sreeja, M. Aquino, M. Terkildsen, P. T. Jayachandran, Y. Jiao, Y. T. Morton, J. M. Ruohoniemi, E. G. Thomas, Y. Zhang, A. T. Weatherwax, L. Alfonsi, G. De Franceschi, and V. Romano (2015), GPS phase scintillation at high latitudes during geomagnetic storms of 7-17 March 2012 - Part 2: Interhemispheric comparison, Ann. Geophys., 33, 657-670, doi:10.5194/angeo-33-657-2015.
Dense plasma and Kelvin-Helmholtz waves at Earth's dayside magnetopause
Walsh, B. M., E. G. Thomas, K.-J. Hwang, J. B. H. Baker, J. M. Ruohoniemi, and J. W. Bonnell (2015), Dense plasma and Kelvin-Helmholtz waves at Earth's dayside magnetopause, J. Geophys. Res. Space Physics, 120, 5560-5573, doi:10.1002/2015JA021014.
Formation of polar ionospheric tongue of ionization during minor geomagnetic disturbed conditions
Liu, J., T. Nakamura, L. Liu, W. Wang, N. Balan, T. Nishiyama, M. R. hairston, and E. G. Thomas (2015), Formation of polar ionospheric tongue of ionization during minor geomagnetic disturbed conditions, J. Geophys. Res. Space Physics, 120, 6860-6873, doi:10.1002/2015JA021393.
Observations of storm time midlatitude ion-neutral coupling using SuperDARN radars and NATION Fabry-Perot interferometers
Joshi, P. P., J. B. H. Baker, J. M. Ruohoniemi, J. J. Makela, D. J. Fisher, B. J. Harding, N. A. Frissell, and E. G. Thomas (2015), Observations of storm time midlatitude ion-neutral coupling using SuperDARN radars and NATION Fabry-Perot interferometers, J. Geophys. Res. Space Physics, 120, 8989-9003, doi:10.1002/2015JA021475.
Multi-instrument, high-resolution imaging of polar cap patch transportation
Thomas, E. G., K. Hosokawa, J. Sakai, J. B. H. Baker, J. M. Ruohoniemi, S. Taguchi, K. Shiokawa, Y. Otsuka, A. J. Coster, J.-P. St.-Maurice, and K. A. McWilliams (2015), Multi-instrument, high-resolution imaging of polar cap patch transportation, Radio Sci., 50, 904-915, doi:10.1002/2015RS005672.
GPS Phase Scintillation at High Latitudes during Two Geomagnetic Storms
Prikryl, P., R. Ghoddousi-Fard, J. M. Ruohoniemi, and E. G. Thomas (2015), GPS Phase Scintillation at High Latitudes during Two Geomagnetic Storms, in Auroral Dynamics and Space Weather (eds Y. Zhang and L. J. Paxton), John Wiley & Sons, Inc, Hoboken, NJ, doi:10.1002/9781118978719.ch15.
The geomagnetic storm time response of GPS total electron content in the North American sector
Thomas, E. G., J. B. H. Baker, J. M. Ruohoniemi, A. J. Coster, and S.-R. Zhang (2016), The geomagnetic storm time response of GPS total electron content in the North American sector, J. Geophys. Res. Space Physics, 121, 1744-1759, doi:10.1002/2015JA022182.
Earth's ion upflow associated with polar cap patches: Global and in situ observations
Zhang, Q.-H., M. Lockwood, R. Heelis, M. Hairston, J. Liang, I. McCrea, B.-C. Zhang, J. Moen, S.-R. Zhang, Y. Zhang, J. M. Ruohoniemi, M. Lester, E. G. Thomas, R.-Y. Liu, M. W. Dunlop, Y. Liu, and Y.-Z. Ma (2016), Earth's ion upflow associated with polar cap patches: Global and in situ observations, Geophys. Res. Lett., 43, 1845-1853, doi:10.1002/2016GL067897.
Polar cap patch transportation beyond the classic scenario
Zhang, Q.-H., J. Moen, M. Lockwood, I. McCrea, B.-C. Zhang, K. A. McWilliams, Q.-G. Zong, S.-R. Zhang, J. M. Ruohoniemi, E. G. Thomas, M. W. Dunlop, R.-Y. Liu, H. Yang, H.-Q. Hu, and M. Lester (2016), Polar cap patch transportation beyond the classic scenario, J. Geophys. Res. Space Physics, 121, 9063-9074, doi:10.1002/2016JA022443.
Solar Cycle 24 Observations of Storm Enhanced Density and the Tongue of Ionization
Coster, A. J., P. J. Erickson, J. C. Foster, E. G. Thomas, J. M. Ruohoniemi, and J. B. H. Baker (2016), Solar Cycle 24 Observations of Storm Enhanced Density and the Tongue of Ionization, in Ionospheric Space Weather: Longitude and Hemispheric Dependencies and Lower Atmosphere Forcing (eds T. Fuller-Rowell, E. Yizengaw, P. H. Doherty, and S. Basu), John Wiley & Sons, Inc, Hoboken, NJ, doi:10.1002/9781118929216.ch6.
GPS phase scintillation at high latitudes during the geomagnetic storm of March 17-18, 2015
Prikryl, P., R. Ghoddousi-Fard, J. M. Weygand, A. Viljanen, M. Connors, D. W. Danskin, P. T. Jayachandran, K. S. Jacobsen, Y. L. Andalsvik, E. G. Thomas, J. M. Ruohoniemi, T. Durgonics, K. Oksavik, E. Spanswick, M. Aquino, and V. Sreeja (2016), GPS phase scintillation at high latitudes during the geomagnetic storm of March 17-18, 2015, J. Geophys. Res. Space Physics, 121, 10,448-10,465, doi:10.1002/2016JA023171.
PFISR observation of intense ion upflow fluxes associated with an SED during the 1 June 2013 geomagnetic storm
Zou, S., A. J. Ridley, X. Jia, E. Boyd, M. J. Nicolls, A. J. Coster, E. G. Thomas, and J. M. Ruohoniemi (2017), PFISR observation of intense ion upflow fluxes associated with an SED during the 1 June 2013 geomagnetic storm, J. Geophys. Res. Space Physics, 122, 2589-2604, doi:10.1002/2016JA023697.
Statistical characterization of the large-scale structure of the subauroral polarization stream
Kunduri, B. S. R., J. B. H. Baker, J. M. Ruohoniemi, E. G. Thomas, S. G. Shepherd, and K. T. Sterne (2017), Statistical characterization of the large-scale structure of the subauroral polarization stream, J. Geophys. Res. Space Physics, 122, 6035-6048, doi:10.1002/2017JA024131.
Ionospheric F-region response to the 26 September 2011 geomagnetic storm in the Antarctic American and Australian sectors
Correia, E., L. Spogli, L. Alfonsi, C. Cesaroni, A. M. Gulisano, E. G. Thomas, R. F. H. Ramirez, and A. A. Rodel (2017), Ionospheric F-region response to the 26 September 2011 geomagnetic storm in the Antarctic American and Australian sectors, Ann. Geophys., 35, 1113-1129, doi:10.5194/angeo-35-1113-2017.
Statistical patterns of ionospheric convection derived from mid-latitude, high-latitude, and polar SuperDARN HF radar observations
Thomas, E. G., and S. G. Shepherd (2018), Statistical patterns of ionospheric convection derived from mid-latitude, high-latitude, and polar SuperDARN HF radar observations, J. Geophys. Res. Space Physics, 123, 3196-3216, doi:10.1002/2018JA025280.
Polar traveling ionospheric disturbances inferred with the B-spline method and associated scintillations in the Southern Hemisphere
Priyadarshi, S., Q.-H. Zhang, E. G. Thomas, L. Spogli, and C. Cesaroni (2018), Polar traveling ionospheric disturbances inferred with the B-spline method and associated scintillations in the Southern Hemisphere, Adv. Space Res., 62, 3249-3266, doi:10.1016/j.asr.2018.08.015.
Review of the accomplishments of mid-latitude Super Dual Auroral Radar Network (SuperDARN) HF radars
Nishitani, N., J. M. Ruohoniemi, M. Lester, J. B. H. Baker, A. V. Koustov, S. G. Shepherd, G. Chisham, T. Hori, E. G. Thomas, R. A. Makarevich, A. Marchaudon, P. Ponomarenko, J. A. Wild, S. E. Milan, W. A. Bristow, J. Devlin, E. Miller, R. A. Greenwald, T. Ogawa, and T. Kikuchi (2019), Review of the accomplishments of mid-latitude Super Dual Auroral Radar Network (SuperDARN) HF radars, Prog Earth Planet Sci, 6:27, doi:10.1186/s40645-019-0270-5.
Morphological study on the ionospheric variability at Bharati, a polar cusp station in the southern hemisphere
Shreedevi, P. R., R. K. Choudhary, Y. Yu, and E. G. Thomas (2019), Morphological study on the ionospheric variability at Bharati, a polar cusp station in the southern hemisphere, J. Atmos. Sol.-Terr. Phys., 193, 105058, doi:10.1016/j.jastp.2019.105058.
Separation and quantification of ionospheric convection sources: 2. The dipole tilt angle influence on reverse convection cells during northward IMF
Reistad, J. P., K. M. Laundal, N. Østgaard, A. Ohma, E. G. Thomas, S. Haaland, K. Oksavik, and S. E. Milan (2019), Separation and quantification of ionospheric convection sources: 2. The dipole tilt angle influence on reverse convection cells during northward IMF, J. Geophys. Res. Space Physics, 124, 6182-6194, doi:10.1029/2019JA026641.
Spatial variation in the responses of the surface external and induced magnetic field to the solar wind
Shore, R. M., M. P. Freeman, J. C. Coxon, E. G. Thomas, J. W. Gjerloev, and N. Olsen (2019), Spatial variation in the responses of the surface external and induced magnetic field to the solar wind, J. Geophys. Res. Space Physics, 124, 6195-6211, doi:10.1029/2019JA026543.
Polar cap patch prediction in the expanding contracting polar cap paradigm
Fæhn Follestad, A., L. B. N. Clausen, E. G. Thomas, Y. Jin, and A. J. Coster (2019), Polar cap patch prediction in the expanding contracting polar cap paradigm, Space Weather, 17, 1570-1583, doi:10.1029/2019SW002276.
AMPERE polar cap boundaries
Burrell, A. G., G. Chisham, S. E. Milan, L. Kilcommons, Y.-J. Chen, E. G. Thomas, and B. Anderson (2020), AMPERE polar cap boundaries, Ann. Geophys., 38, 481-490, doi:10.5194/angeo-38-481-2020.
An improved estimation of SuperDARN Heppner-Maynard Boundaries using AMPERE data
Fogg, A. R., M. Lester, T. K.Yeoman, A. G. Burrell, S. M. Imber, S. E. Milan, E. G. Thomas, H. Sangha, and B. J. Anderson (2020), An improved estimation of SuperDARN Heppner-Maynard Boundaries using AMPERE data, J. Geophys. Res. Space Physics, 125, e2019JA027218, doi:10.1029/2019JA027218.
Bistatic observations with SuperDARN HF radars: First results
Shepherd, S. G., K. T. Sterne, E. G. Thomas, J. M. Ruohoniemi, J. B. H. Baker, R. T. Parris, T. R. Pedersen, and J. M. Holmes (2020), Bistatic observations with SuperDARN HF radars: First results, Radio Sci., 55, e2020RS007121, doi:10.1029/2020RS007121.
Geomagnetic storm induced plasma density enhancements in the southern polar ionospheric region: a comparative study using St. Patrick's day storms of 2013 and 2015
Shreedevi, P. R., R. K. Choudhary, S. V. Thampi, S. Yadav, T. K. Pant, Y. Yu, R. M. McGranaghan, E. G. Thomas, A. Bhardwaj, and A. K. Sinha (2020), Geomagnetic storm induced plasma density enhancements in the southern polar ionospheric region: a comparative study using St. Patrick's day storms of 2013 and 2015, Space Weather, 18, e2019SW002383, doi:10.1029/2019SW002383.
Comparison of interferometer calibration techniques for improved SuperDARN elevation angles
Chisham, G., A. G. Burrell, A. Marchaudon, S. G. Shepherd, E. G. Thomas, and P. V. Ponomarenko (2021), Comparison of interferometer calibration techniques for improved SuperDARN elevation angles, Polar Science, 28, 100638, doi:10.1016/j.polar.2021.100638.
Editorial: Special issue: “SuperDARN / Studies of Geospace Dynamics - Today and Future”
Yukimatu, A. S., A. Grocott, E. G. Thomas, T. Nagatsuma, N. Nishitani, K. Hosokawa, and M. Watanabe (2021), Editorial: Special issue: "SuperDARN / Studies of Geospace Dynamics - Today and Future", Polar Science, 28, 100690, doi:10.1016/j.polar.2021.100690.
Quantifying the lobe reconnection rate during dominant IMF By periods and different dipole tilt orientations
Reistad, J. P., K. M. Laundal, N. Østgaard, A. Ohma, A. G. Burrell, S. M. Hatch, S. Haaland, and E. G. Thomas (2021), Quantifying the lobe reconnection rate during dominant IMF By periods and different dipole tilt orientations, J. Geophys. Res. Space Physics, 126, e2021JA029742, doi:10.1029/2021JA029742.
Super Dual Auroral Radar Network expansion and its influence on the derived ionospheric convection pattern
Walach, M.-T., A. Grocott, F. Staples, and E. G. Thomas (2022), Super Dual Auroral Radar Network expansion and its influence on the derived ionospheric convection pattern, J. Geophys. Res. Space Physics, 127, e2021JA029559, doi:10.1029/2021JA029559.
Virtual height characteristics of ionospheric and ground scatter observed by mid-latitude SuperDARN HF radars
Thomas, E. G., and S. G. Shepherd (2022), Virtual height characteristics of ionospheric and ground scatter observed by mid-latitude SuperDARN HF radars, Radio Sci., 57, e2022RS007429, doi:10.1029/2022RS007429.
Ionospheric boundaries derived from auroral images
Chisham, G., A. G. Burrell, E. G. Thomas, and Y.-J. Chen (2022), Ionospheric boundaries derived from auroral images, J. Geophys. Res. Space Physics, 127, e2022JA030622, doi:10.1029/2022JA030622.
Traveling ionospheric disturbances in the vicinity of storm enhanced density at midlatitudes
Zhang, S.-R., Y. Nishimura, P. J. Erickson, E. Aa, H. Kil, Y. Deng, E. G. Thomas, W. Rideout, A. J. Coster, R. Kerr, and J. Vierinen (2022), Traveling ionospheric disturbances in the vicinity of storm enhanced density at midlatitudes, J. Geophys. Res. Space Physics, 127, e2022JA030429, doi:10.1029/2022JA030429.
An examination of SuperDARN backscatter modes using machine learning guided by ray-tracing
Kunduri, B. S. R., J. B. H. Baker, J. M. Ruohoniemi, E. G. Thomas, and S. G. Shepherd (2022), An examination of SuperDARN backscatter modes using machine learning guided by ray-tracing, Space Weather, 20, e2022SW003130, doi:10.1029/2022SW003130.
Multi-instrument observations of polar cap patches and traveling ionospheric disturbances generated by solar wind Alfvén waves coupling to the dayside magnetosphere
Prikryl, P., R. G. Gillies, D. R. Themens, J. M. Weygand, E. G. Thomas, and S. Chakraborty (2022), Multi-instrument observations of polar cap patches and traveling ionospheric disturbances generated by solar wind Alfven waves coupling to the dayside magnetosphere, Ann. Geophys., 40, 619-639, doi:10.5194/angeo-40-619-2022.
Dusk-dawn asymmetries in SuperDARN convection maps
Walach, M.-T., A. Grocott, E. G. Thomas, and F. Staples (2022), Dusk-dawn asymmetries in SuperDARN convection maps, J. Geophys. Res. Space Physics, 127, e2022JA030906, doi:10.1029/2022JA030906.
Multi-frequency SuperDARN interferometer calibration
Thomas, E. G., S. G. Shepherd, and G. Chisham (2024), Multi-frequency SuperDARN interferometer calibration, Radio Sci., 59, e2024RS007957, doi:10.1029/2024RS007957.
HF radar observations and modeling of the impact of the 8 April 2024 total solar eclipse on the ionosphere-thermosphere system
Kunduri, B. S. R., J. B. H. Baker, J. M. Ruohoniemi, E. G. Thomas, J. D. Huba, D. J. Emmons, D. R. Themens, K. T. Sterne, G. Farinas Perez, W. A. Bristow, S. G. Shepherd, J. M. Holmes, E. V. Dao, A. T. Chartier, G. W. Perry, and K. Pandey (2024), HF radar observations and modeling of the impact of the 8 April 2024 total solar eclipse on the ionosphere-thermosphere system, Geophys. Res. Lett., 51, e2024GL112484, doi:10.1029/2024GL112484.
Multi-frequency SuperDARN HF radar observations of the ionospheric response to the October 2023 annular solar eclipse
Thomas, E. G., S. G. Shepherd, B. S. R. Kunduri, and D. R. Themens (2024), Multi-frequency SuperDARN HF radar observations of the ionospheric response to the October 2023 annular solar eclipse, Geophys. Res. Lett., 51, e2024GL112450, doi:10.1029/2024GL112450.
Observation and simulation studies of ionospheric F-region in the South American and Antarctic sectors in the intense geomagnetic storm of August 2018
de Abreu, A. J., E. Correia, O. F. Jonah, K. Venkatesh, E. G. Thomas, R. de Jesus, M. Roberto, J. R. Abalde, and P. R. Fagundes (2025), Observation and simulation studies of ionospheric F-region in the South American and Antarctic sectors during the intense space weather event of August 2018, J. Atmos. Sol.-Terr. Phys., 266, 106394, doi:10.1016/j.jastp.2024.106394.
Magnetosheath control of the cross polar cap potential: Correcting for measurement uncertainty in space weather
O'Brien, C., B. M. Walsh, and E. G. Thomas (2025), Magnetosheath control of the cross polar cap potential: Correcting for measurement uncertainty in space weather, J. Geophys. Res. Space Physics, 130, e2024JA033468, doi:10.1029/2024JA033468.