Results 51 to 60 of about 723 (151)

Radio‐Quiet Ionosonde Observations for Monitoring Absorption in the HF Band

Radio Science, Volume 61, Issue 8, August 2026.
Abstract This work presents a technique to monitor ionospheric absorption in the HF radio band using ionosondes. For this purpose, the ionosondes were run in a radio‐silent mode, recording not reflections of their own emitted signals but oblique signals from transmitters of opportunity.
T. G. W. Verhulst, A. Buzás, D. Altadill, A. Segarra, V. de Paula, V. Barta   +5 more
wiley   +1 more source

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

Geophysical Research Letters
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.
B. S. R. Kunduri, 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, K. Pandey   +15 more
doaj   +1 more source

Climatology of Satellite Traces over European Mid-Latitudes and Their Association with Travelling Ionospheric Disturbances

Applied Sciences
Satellite traces (STs) are additional ionogram echoes associated with off-vertical reflections from spatially structured F-region plasma. This study investigates the climatology of STs over the European mid-latitude ionosphere using Digisonde ionograms ...
Ankitha Nandakumar, Haris Haralambous, Ola Abu Elezz, Blessy Varghese, Krishnendu Sekhar Paul, Tiju Joseph Mathew   +5 more
doaj   +1 more source

Retrieval of thermospheric parameters from routine ionospheric observations: assessment of method’s performance at mid-latitudes daytime hours

Journal of Space Weather and Space Climate, 2012
A new method has been developed to retrieve neutral temperature Tn and composition [O], [N2], [O2] from electron density profiles in the daytime mid-latitude F2-region under both quiet and disturbed conditions. A comparison with CHAMP neutral gas density
Zolesi B., Perrone L., Belehaki A., Mikhailov A.V., Tsagouri I.   +4 more
doaj   +1 more source

Physics‐Embedded Deep Learning Reveals the Memory Effect of Ionospheric Electron Density in Response to Solar EUV Forcing

Geophysical Research Letters, Volume 53, Issue 14, 28 July 2026.
Abstract Precise characterization of the electron density profile is crucial for optimizing high frequency communications. Reconstruction models often assume an instantaneous ionospheric response to solar forcing or using time delays, neglecting the time‐integrated cumulative “memory effect” of plasma dynamics.
Hongwei Gong, Hanxian Fang, Die Duan, Chao Xiao, Jintai Li, Chenghao Li, Hongtao Huang, Ganming Ren, Chuyue Zhou, Han Wu   +9 more
wiley   +1 more source

Comparison of the topside ionosphere scale height determined by topside sounders model and bottomside digisonde profiles

, 2006
Topside ionospheric electron density extrapolation techniques rely on the applied profiler model with different techniques resulting in different profile shape.
Marinov, P., Jakowski, N., Stanimir Stankov, Kutiev, I., Stankov, S. M., Pencho Marinov, Belehaki, A., A. Belehaki, Ivan Kutiev, Norbert Jakowski   +9 more
core   +1 more source

Southern high-latitude Digisonde observations of ionosphere E-region Bragg scatter during intense lacuna conditions [PDF]

Annales Geophysicae, 2004
During summer months at solar cycle minimum, F-region lacuna and slant-Es conditions (SEC) are common features of daytime ionograms recorded around local magnetic noon at Casey, Antarctica. Digisonde measurements of drift velocity height profiles show
D. P. Monselesan, D. P. Monselesan, R. J. Morris, P. L. Dyson, M. R. Hyde, M. R. Hyde   +5 more
doaj   +1 more source

Direct Observations of Large‐Scale Wave Structure and Post‐Sunset Rise of the Ionosphere in the Generation of Equatorial Spread F

Geophysical Research Letters, Volume 53, Issue 13, 16 July 2026.
Abstract Large‐scale wave structure (LSWS) and the post‐sunset rise (PSSR) are two key factors in the generation of equatorial spread F (ESF). In this study, we reported continuous and direct observations of LSWS and PSSR and their effects on seeding ESF by Sanya incoherent scatter radar (SYISR) and ionosonde in September–October 2024.
Qi Jiang, Jiuhou Lei, Xinan Yue, Fuqing Huang, Rong Xia, Tong Dang, Xiaoli Luan   +6 more
wiley   +1 more source

A comparison of f0F hmE model calculations with El Arenosillo digisonde observations. Seasonal variations

, 1999
Seasonal variations of hmE and f0F2 are analyzed using El Arenosillo digisonde observations during solar minimum (1995-1996). Unlike some widely used empirical models daytime hmE show seasonal variations with winter hmE being higher than summer ones and ...
de la Morena, B. A., Miro, G., Mikhailov, A. V., Marin, D.   +3 more
core   +3 more sources

Optimizing HAARP Beam Pattern for Generation of Strong F‐Region Field‐Aligned Irregularities

Radio Science, Volume 61, Issue 7, July 2026.
Abstract Field‐aligned irregularities (FAIs) are the signatures of plasma turbulence and convection in the mid‐ and high‐latitude F‐region ionosphere, and also provide coherent backscatter targets for HF radars. To serve irregularity generation and characterization studies, we conducted experiments at the High‐frequency Active Auroral Research Program (
T. S. Anderson, E. H. Lay, I. T. Cummings, C. A. Jeffery, P. A. Bernhardt, M. McCarrick, W. A. Bristow, S. J. Briczinski   +7 more
wiley   +1 more source