Results 11 to 20 of about 83 (58)

Correlation between cosmic noise absorption and VHF coherent echo intensity [PDF]

, 2005
International audienceWe present examples and statistical analysis of the events with statistically significant correlation between the cosmic noise absorption (CNA) and the signal-to-noise ratio (SNR) of the VHF coherent echo intensity in the area ...
Makarevitch, R.A., Makarevitch, R. A., F. Honary, Honary, F., R. A. Makarevitch   +4 more
core   +2 more sources

“Caterpillar” ULF Waves in the Dusk Side Sub‐Auroral Region: Conjugate Observations With SuperDARN, Arase and Ground Magnetometers

Journal of Geophysical Research: Space Physics, Volume 131, Issue 5, May 2026.
Abstract On 23 November 2022, during exceptionally quiet geomagnetic conditions, a distinct ultra‐low frequency (ULF) wave in the Pc5 band (∼2.4 mHz) was observed in the duskside sub‐auroral region by two Canadian SuperDARN (Super Dual Auroral Radar Network) radars.
N. Nishitani, K. Hosokawa, T. Hori, M. Teramoto, P. V. Ponomarenko, A. Shinbori, Y. Obana, A. S. Yukimatu, G. Hussey, Y. Miyoshi, A. Matsuoka, A. Kumamoto, F. Tsuchiya, S. Matsuda, Y. Kasahara, S. Nakamura, I. Shinohara, Y. Zhang, L. Paxton   +18 more
wiley   +1 more source

Monitoring Flood Inundation Dynamics From Space

Reviews of Geophysics, Volume 64, Issue 1, March 2026.
Abstract With the increasing intensity and frequency of flood events worldwide, the need for accurate and timely inundation mapping has never been more critical. Large‐scale flood extent estimations are vital for coordinating effective disaster response, facilitating recovery, and building future resilience.
C. Campo, P. Tamagnone, S. Choy, T. D. Tran, G. J.‐P. Schumann, Y. Kuleshov   +5 more
wiley   +1 more source

Characterization of a Lava Plain NW of Ascraeus Mons, Mars, Through Surface Morphometric Analyses and SHARAD Subsurface Detections

Journal of Geophysical Research: Planets, Volume 131, Issue 1, January 2026.
Abstract The Martian lava plains are characterized by their extensive, low‐relief surfaces, which are the result of numerous basaltic eruptions and feature a variety of volcanic landforms, including vents, cones, pits, and skylights. The combination of these features and impact craters yields a significant understanding of the planet's geological past ...
G. Nodjoumi, S. E. Lauro, M. Valiante, E. Luzzi, A. P. Rossi   +4 more
wiley   +1 more source

Forecasting Equatorial Plasma Bubbles From Precursor TEC Signatures Observed by C/NOFS

Space Weather, Volume 24, Issue 1, January 2026.
Abstract This study investigates the potential of localized total electron content (TEC) perturbation measurements, possibly associated with bottomside upwelling of the F‐layer, as precursors for forecasting ionospheric plasma irregularities, particularly the equatorial plasma bubbles (EPBs).
S. K. Das, C. Stolle, Y. Yamazaki, T. Yokoyama, M. Yamamoto, S. Perwitasari   +5 more
wiley   +1 more source

Upwelling Metallic Ions Producing Valley Region Irregularities Over Low Latitude During the 2025 New Year Magnetic Storm

Geophysical Research Letters, Volume 52, Issue 24, 28 December 2025.
Abstract Valley region irregularities (VRIs) have been previously investigated using radar, ionosonde, and rocket‐borne in situ observations. In this paper, based on a joint observational experiment by lidar and radars performed in Hainan, China, we report a case of low‐latitude VRIs generated in association with uplifted metallic ions for the first ...
Jing Jiao, Wenjie Sun, Guozhu Li, Yajun Zhu, Biqiang Zhao, Guotao Yang, Tatsuhiro Yokoyama, Septi Perwitasari, Lianhuan Hu, Jianfei Liu, Haiyong Xie, Zhaoguo Huang, Xiaofei Wu, Chunxiao Yan   +13 more
wiley   +1 more source

First Observation of Localized F Region Bottom‐Type Scattering Layer by All‐Sky Radar at Low Latitude

Geophysical Research Letters, Volume 52, Issue 23, 16 December 2025.
Abstract F‐region bottom‐type scattering layers (BSLs) occurring over equatorial and low latitudes may act as the precursor of plasma bubbles, usually observed by narrow‐beam very high frequency radars. However, their spatial features remain unknown due to the radar narrow field‐of‐view.
Wenjie Sun, Guozhu Li, Lianhuan Hu, Biqiang Zhao, Jianfei Liu, Haiyong Xie, Guofeng Dai, Xiukuan Zhao, Yi Li, Baiqi Ning   +9 more
wiley   +1 more source

Ionospheric Response to the Seismic Wave Induced by the Kamchatka Earthquake on July 29, 2025

Russian Journal of Earth Sciences
The July 29, 2025 earthquake near the eastern coast of the Kamchatka Peninsula induced a high-amplitude seismic wave that propagated thousands of kilometers from the epicenter.
Oinats Aleksey, Cedrik Mark, Dyukov Il'ya Yur'evich, Podlesnyi Aleksey, Belinskaya Anastasiya, Borovko Aleksandra, Sorokin Aleksandr, Dobrynin Vasiliy, Dergach Petr Aleksandrovich   +8 more
doaj   +1 more source

Radar Polarimetry in Glaciology: Theory, Measurement Techniques, and Scientific Applications for Investigating the Anisotropy of Ice Masses

Reviews of Geophysics, Volume 63, Issue 4, December 2025.
Abstract Dielectric anisotropy in ice alters the propagation of polarized radio waves, so polarimetric radar sounding can be used to survey anisotropic properties of ice masses. Ice anisotropy is either intrinsic, associated with ice‐crystal orientation fabric (COF), or extrinsic, associated with material heterogeneity, such as bubbles, fractures, and ...
Benjamin H. Hills, T. J. Young, David A. Lilien, Esther Babcock, Nicole Bienert, Donald Blankenship, John Bradford, Giancorrado Brighi, Alex Brisbourne, Jørgen Dall, Reinhard Drews, Olaf Eisen, M. Reza Ershadi, Tamara A. Gerber, Nicholas Holschuh, Daniela Jansen, Thomas M. Jordan, Nanna B. Karlsson, Jilu Li, Carlos Martín, Kenichi Matsuoka, Daniel May, Falk M. Oraschewski, John Paden, Nicholas M. Rathmann, Neil Ross, Dustin M. Schroeder, Martin Siegert, Matthew R. Siegfried, Emma Smith, Ole Zeising   +30 more
wiley   +1 more source

D‐Region Changes and Wave Activity Detected From Unusually Strong VLF Anomalies Associated With the January 2022 Tonga Volcanic Eruption

Journal of Geophysical Research: Space Physics, Volume 130, Issue 11, November 2025.
Abstract We present unusually strong daytime signal amplitude anomalies of 11.1 dB on JJI and 12.6 dB on VTX very low‐frequency (VLF) transmitter signals recorded at Suva, Fiji, due to the powerful Hunga Tonga–Hunga Ha'apai (HTHH) volcanic eruption (VE) on 15 January 2022 around 04:00 UT.
Sushil Kumar, Sarwan Kumar, Mie Ichihara
wiley   +1 more source