Results 11 to 20 of about 7,805 (237)

Multi-frequency HF radar measurements of artificial F-region field-aligned irregularities [PDF]

Annales Geophysicae, 2004
We present radar backscatter power measurements using the CUTLASS HF radar at Hankasalmi, Finland from F-region field-aligned irregularities induced by HF radio pumping with the EISCAT Heating facility.
A. Senior, N. D. Borisov, M. J. Kosch, T. K. Yeoman, F. Honary, M. T. Rietveld   +5 more
doaj   +3 more sources

Effects of high-latitude atmospheric gravity wave disturbances on artificial HF radar backscatter [PDF]

Annales Geophysicae, 2006
Observations of HF radar backscatter from artificial field-aligned irregularities in an ionosphere perturbed by travelling disturbances due to atmospheric gravity waves are presented.
A. Senior, M. J. Kosch, T. K. Yeoman, M. T. Rietveld, I. W. McCrea   +4 more
doaj   +3 more sources

Mapping ionospheric backscatter measured by the SuperDARN HF radars – Part 2: Assessing SuperDARN virtual height models [PDF]

Annales Geophysicae, 2008
The Super Dual Auroral Radar Network (SuperDARN) network of HF coherent backscatter radars form a unique global diagnostic of large-scale ionospheric and magnetospheric dynamics in the Northern and Southern Hemispheres.
T. K. Yeoman, G. Chisham, L. J. Baddeley, R. S. Dhillon, T. J. T. Karhunen, T. R. Robinson, A. Senior, D. M. Wright   +7 more
doaj   +3 more sources

Wind redistribution of snow impacts the Ka- and Ku-band radar signatures of Arctic sea ice [PDF]

The Cryosphere, 2023
Wind-driven redistribution of snow on sea ice alters its topography and microstructure, yet the impact of these processes on radar signatures is poorly understood. Here, we examine the effects of snow redistribution over Arctic sea ice on radar waveforms
V. Nandan, V. Nandan, R. Willatt, R. Mallett, R. Mallett, J. Stroeve, J. Stroeve, T. Geldsetzer, R. Scharien, R. Tonboe, J. Yackel, J. Landy, D. Clemens-Sewall, A. Jutila, D. N. Wagner, D. N. Wagner, D. Krampe, M. Huntemann, M. Mahmud, D. Jensen, T. Newman, S. Hendricks, G. Spreen, A. Macfarlane, M. Schneebeli, J. Mead, R. Ricker, M. Gallagher, C. Duguay, C. Duguay, I. Raphael, C. Polashenski, M. Tsamados, I. Matero, M. Hoppmann   +34 more
doaj   +1 more source

A comparison of overshoot modelling with observations of polar mesospheric summer echoes at radar frequencies of 56 and 224 MHz [PDF]

Annales Geophysicae, 2015
We have compared radar observations of polar mesospheric summer echoes (PMSEs) modulated by artificial electron heating, at frequencies of 224 MHz (EISCAT VHF) and 56 MHz (MORRO). We have concentrated on 1 day of observation, lasting ~ 3.8 h.
O. Havnes, H. Pinedo, C. La Hoz, A. Senior, T. W. Hartquist, M. T. Rietveld, M. J. Kosch, M. J. Kosch   +7 more
doaj   +1 more source

94 GHz Radar Backscatter Characteristics of Alpine Glacier Ice

Geophysical Research Letters, 2023
Measuring the radar backscatter characteristics of glacier ice at different frequencies and incidence angles is fundamental to predicting the glacier mapping performance of a sensor. However, such measurements at 94 GHz do not exist.
W. D. Harcourt, D. A. Robertson, D. G. Macfarlane, B. R. Rea, M. Spagnolo   +4 more
doaj   +1 more source

Radiometric Comparison within the Sentinel-1 SAR Constellation over a Wide Backscatter Range

Remote Sensing, 2020
Radiometric calibration adjusts the measured pixel intensity to a physical property, the radar cross section (RCS). After calibration, this relationship is defined over the entire backscatter range: from low image power (near noise) up to high ...
Kersten Schmidt, Marco Schwerdt, Nuno Miranda, Jens Reimann   +3 more
doaj   +1 more source

Investigation of the relationship between optical auroral forms and HF radar E region backscatter [PDF]

, 2000
International audienceThe SuperDARN HF radars have been employed in the past to investigate the spectral characteristics of coherent backscatter from L-shell aligned features in the auroral E region.
Milan, S. E., N. Sato, Lester, M., H. Takizawa (7612496), Villain, J.-P., J. -p. Villain, Takizawa, H., M. Lester, N. Sato (7606136), Milan, S.E., S. E. Milan, Stephen E. Milan (7612220), J. P. Villain (7612424), J.-P. Villain, Mark Lester (6477935), Sato, N., H. Takizawa   +16 more
core   +1 more source

Physics-Based Forward Modeling of Ocean Surface Swell Effects on SMAP L1-C NRCS Observations

Sensors, 2022
This paper examines the impact of ocean surface swell waves on near-coastal L-band high-resolution synthetic aperture radar (SAR) data collected using the National Aeronautics and Space Administration’s (NASA) Soil Moisture Active/Passive (SMAP) radar at
Shanka N. Wijesundara, Joel T. Johnson
doaj   +1 more source

Optical, radar, and magnetic observations of magnetosheath plasma capture during a positive IMF B_z impulse [PDF]

Annales Geophysicae, 2008
We present a multi-instrument study of the ionospheric response to a northward turning of the IMF. The observations were made in the near-noon (11:00 MLT) sector on Svalbard (at 75° MLAT).
V. Safargaleev, A. Kozlovsky, A. Kozlovsky, T. Sergienko, T. K. Yeoman, M. Uspensky, D. M. Wright, H. Nilsson, T. Turunen, A. Kotikov   +9 more
doaj   +1 more source