Articles | Volume 33, issue 11
https://doi.org/10.5194/angeo-33-1369-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Special issue:
https://doi.org/10.5194/angeo-33-1369-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Review paper
| 
10 Nov 2015
Review paper |
| 10 Nov 2015
Defining and resolving current systems in geospace
N. Y. Ganushkina
CORRESPONDING AUTHOR
Earth Observations Department, Finnish Meteorological Institute, Helsinki, Finland
Department of Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, Michigan, USA
M. W. Liemohn
Department of Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, Michigan, USA
S. Dubyagin
Earth Observations Department, Finnish Meteorological Institute, Helsinki, Finland
I. A. Daglis
Department of Physics, University of Athens, Panepistimiopolis Zografou, 15784 Athens, Greece
I. Dandouras
Astrophysics and Planetary Science Research Institute, CNRS/University of Toulouse, Toulouse, France
D. L. De Zeeuw
Department of Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, Michigan, USA
Y. Ebihara
Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji, Kyoto, Japan
R. Ilie
Department of Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, Michigan, USA
R. Katus
Department of Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, Michigan, USA
M. Kubyshkina
Institute of Physics, University of St. Petersburg, St. Petersburg, Russia
S. E. Milan
Department of Physics and Astronomy, University of Leicester, Leicester, UK
Birkeland Centre for Space Science, Department of Physics and Technology, University of Bergen, Bergen, Norway
S. Ohtani
Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, USA
N. Ostgaard
Birkeland Centre for Space Science, Department of Physics and Technology, University of Bergen, Bergen, Norway
J. P. Reistad
Birkeland Centre for Space Science, Department of Physics and Technology, University of Bergen, Bergen, Norway
P. Tenfjord
Birkeland Centre for Space Science, Department of Physics and Technology, University of Bergen, Bergen, Norway
F. Toffoletto
Physics and Astronomy Department, Rice University, Houston, Texas, USA
S. Zaharia
ISR-1 Division, Los Alamos National Laboratory, Los Alamos, New Mexico, USA
O. Amariutei
Earth Observations Department, Finnish Meteorological Institute, Helsinki, Finland
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This article is included in the Encyclopedia of Geosciences
Casper Rutjes, David Sarria, Alexander Broberg Skeltved, Alejandro Luque, Gabriel Diniz, Nikolai Østgaard, and Ute Ebert
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This article is included in the Encyclopedia of Geosciences
K. Kauristie, M. V. Uspensky, N. G. Kleimenova, O. V. Kozyreva, M. M. J. L. Van De Kamp, S. V. Dubyagin, and S. Massetti
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This article is included in the Encyclopedia of Geosciences
C. Tsironis, A. Anastasiadis, C. Katsavrias, and I. A. Daglis
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R. Kataoka, Y. Fukuda, H. A. Uchida, H. Yamada, Y. Miyoshi, Y. Ebihara, H. Dahlgren, and D. Hampton
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This article is included in the Encyclopedia of Geosciences
V. A. Sergeev, I. A. Chernyaev, V. Angelopoulos, and N. Y. Ganushkina
Ann. Geophys., 33, 1485–1493, https://doi.org/10.5194/angeo-33-1485-2015, https://doi.org/10.5194/angeo-33-1485-2015, 2015
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Adaptive magnetospheric models based on THEMIS magnetic observations made at 6-9Re in the nightside magnetosphere are used to map the magnetically conjugate 30 and 80keV proton isotropy boundaries (IBs) to investigate the value of Kib=Rc/rc (magnetic curvature radius to particle gyroradius) in the neutral sheet at the IB generation place. For the most accurate mapping, the group Kib spread spans from 4 to 32; its median value is ~13, slightly larger than Kib8 expected for current sheet scatter.
This article is included in the Encyclopedia of Geosciences
M. Georgiou, I. A. Daglis, E. Zesta, G. Balasis, I. R. Mann, C. Katsavrias, and K. Tsinganos
Ann. Geophys., 33, 1431–1442, https://doi.org/10.5194/angeo-33-1431-2015, https://doi.org/10.5194/angeo-33-1431-2015, 2015
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Our study demonstrates a remarkable association between the earthward penetration of ULF waves and radiation belt electron enhancements during four magnetic storms that occurred in 2001. In the past, ULF waves had been observed at unusual depths during rare superstorms. But ULF wave activity, reaching magnetic shells as low as 2, was also observed during relatively intense storms when it played a key role in diffusing electrons radially inward and thereby accelerating them to higher energies.
This article is included in the Encyclopedia of Geosciences
E. Lee, G. K. Parks, S. Y. Fu, M. Fillingim, Y. B. Cui, J. Hong, I. Dandouras, and H. Rème
Ann. Geophys., 33, 1263–1269, https://doi.org/10.5194/angeo-33-1263-2015, https://doi.org/10.5194/angeo-33-1263-2015, 2015
G. Balasis, I. A. Daglis, I. R. Mann, C. Papadimitriou, E. Zesta, M. Georgiou, R. Haagmans, and K. Tsinganos
Ann. Geophys., 33, 1237–1252, https://doi.org/10.5194/angeo-33-1237-2015, https://doi.org/10.5194/angeo-33-1237-2015, 2015
C. Katsavrias, I. A. Daglis, W. Li, S. Dimitrakoudis, M. Georgiou, D. L. Turner, and C. Papadimitriou
Ann. Geophys., 33, 1173–1181, https://doi.org/10.5194/angeo-33-1173-2015, https://doi.org/10.5194/angeo-33-1173-2015, 2015
V. A. Sergeev, S. A. Chernyaeva, S. V. Apatenkov, N. Y. Ganushkina, and S. V. Dubyagin
Ann. Geophys., 33, 1059–1070, https://doi.org/10.5194/angeo-33-1059-2015, https://doi.org/10.5194/angeo-33-1059-2015, 2015
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We investigate the precipitated-to-trapped flux ratio patterns near the proton isotropy boundary (IB) using NOAA-POES observations. For 30 and 80keV proton energies, we found only 31% of events showing the dispersion pattern predicted by the non-adiabatic scattering in the tail current sheet. Most frequent pattern had no measureable IB energy dispersion (63%); structured IBs with a few Jprec/Jtrap dropouts were also usual (60%). Roles of current sheet and wave-induced scattering are discussed.
This article is included in the Encyclopedia of Geosciences
M. W. Liemohn, R. M. Katus, and R. Ilie
Ann. Geophys., 33, 965–982, https://doi.org/10.5194/angeo-33-965-2015, https://doi.org/10.5194/angeo-33-965-2015, 2015
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The different electric current systems flowing in the near-Earth nightside magnetosphere each have a unique contribution to the magnetic and electric field distortion of geospace. This study quantifies the intensity and timing of five current systems as calculated from 90 storm events using an inner magnetospheric drift physics model. There is a systematic progression through the various current systems, leading to implications for nonlinear feedback on the geospace system.
This article is included in the Encyclopedia of Geosciences
A. V. Nikolaev, V. A. Sergeev, N. A. Tsyganenko, M. V. Kubyshkina, H. Opgenoorth, H. Singer, and V. Angelopoulos
Ann. Geophys., 33, 505–517, https://doi.org/10.5194/angeo-33-505-2015, https://doi.org/10.5194/angeo-33-505-2015, 2015
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In this study we use two-loop model SCW (SCW2L) to quantitatively investigate distortion of the ionospheric footpoint pattern in response to changes of different SCW2L parameters. Calculation results show that SCW-related footprint shifts result in formation of auroral bulge and westward travelling surge and may contribute to rotation of auroral streamers, and that SCW2L combined with the AM03 model nicely describes the azimuthal progression and the observed magnitude of the auroral expansion.
This article is included in the Encyclopedia of Geosciences
G. K. Parks, E. Lee, S. Y. Fu, M. Fillingim, I. Dandouras, Y. B. Cui, J. Hong, and H. Rème
Ann. Geophys., 33, 333–344, https://doi.org/10.5194/angeo-33-333-2015, https://doi.org/10.5194/angeo-33-333-2015, 2015
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Ions from Earth's ionosphere continually escape into space. This article examines ions escaping the auroral oval, a region in the polar region of Earth where auroras occur. Previous works have shown that ionospheric ions escape during active auroras, and more as the intensity of the aurora increases. In contrast, we have examined times of no auroras and find that ions are still escaping the auroral ionosphere. These escaping ions are an important source of auroral ions in the magnetosphere.
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A. Varsani, C. J. Owen, A. N. Fazakerley, C. Forsyth, A. P. Walsh, M. André, I. Dandouras, and C. M. Carr
Ann. Geophys., 32, 1093–1117, https://doi.org/10.5194/angeo-32-1093-2014, https://doi.org/10.5194/angeo-32-1093-2014, 2014
A. Blagau, I. Dandouras, A. Barthe, S. Brunato, G. Facskó, and V. Constantinescu
Geosci. Instrum. Method. Data Syst., 3, 49–58, https://doi.org/10.5194/gi-3-49-2014, https://doi.org/10.5194/gi-3-49-2014, 2014
T. M. Giannaros, D. Melas, I. A. Daglis, and I. Keramitsoglou
Nat. Hazards Earth Syst. Sci., 14, 347–358, https://doi.org/10.5194/nhess-14-347-2014, https://doi.org/10.5194/nhess-14-347-2014, 2014
M. Yamauchi, Y. Ebihara, H. Nilsson, and I. Dandouras
Ann. Geophys., 32, 83–90, https://doi.org/10.5194/angeo-32-83-2014, https://doi.org/10.5194/angeo-32-83-2014, 2014
P. Kajdič, X. Blanco-Cano, N. Omidi, K. Meziane, C. T. Russell, J.-A. Sauvaud, I. Dandouras, and B. Lavraud
Ann. Geophys., 31, 2163–2178, https://doi.org/10.5194/angeo-31-2163-2013, https://doi.org/10.5194/angeo-31-2163-2013, 2013
M. Yamauchi, I. Dandouras, H. Rème, R. Lundin, and L. M. Kistler
Ann. Geophys., 31, 1569–1578, https://doi.org/10.5194/angeo-31-1569-2013, https://doi.org/10.5194/angeo-31-1569-2013, 2013
I. Dandouras
Ann. Geophys., 31, 1143–1153, https://doi.org/10.5194/angeo-31-1143-2013, https://doi.org/10.5194/angeo-31-1143-2013, 2013
C. P. Escoubet, J. Berchem, K. J. Trattner, F. Pitout, R. Richard, M. G. G. T. Taylor, J. Soucek, B. Grison, H. Laakso, A. Masson, M. Dunlop, I. Dandouras, H. Reme, A. Fazakerley, and P. Daly
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S. Dubyagin, N. Ganushkina, S. Apatenkov, M. Kubyshkina, H. Singer, and M. Liemohn
Ann. Geophys., 31, 395–408, https://doi.org/10.5194/angeo-31-395-2013, https://doi.org/10.5194/angeo-31-395-2013, 2013
Short summary
A number of current systems exist in the Earth's magnetosphere. It is very difficult to identify local measurements as belonging to a specific current system. Therefore, there are different definitions of supposedly the same current, leading to unnecessary controversy. This study presents a robust collection of these definitions of current systems in geospace, particularly in the near-Earth nightside magnetosphere, as viewed from a variety of observational and computational analysis techniques.
A number of current systems exist in the Earth's magnetosphere. It is very difficult to identify...
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