Abstract
Using the east-west geomagnetic disturbance fields observed from stations at mid-latitudes, we investigate the characteristics of field-aligned currents on the nightside during the April 6, 2000 superstorm. The results indicate that there is an eastward disturbance on the nightside of Northern Hemisphere during the main phase of magnetic storm, while the interplanetary magnetic field (IMF) is continued southward. The positive disturbances in the postmidnight are larger than that in the premidnight. This suggests that upward field-aligned currents develop on the nightside, when the IMF is directed southward. The peak of upward field-aligned currents is located in postmidnight, and it will be more obvious at substorm expansion. We get the conclusion that both partial ring current and region-2 field-aligned current shift to dusk sector. The upward region-2 current is decreased at substorm onset, and intensified after it. We also investigate the relationship between the upward field-aligned currents on the nightside and the auroral electrojets at high latitudes. It shows a good correspondence between region-2 current and the westward electrojet in the postmidnight. We suppose that they are both associated with the convection electric field.
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Sibeck D G. A model for the transient magnetospheric response to sudden solar wind dynamic pressure variations. J Geophys Res, 1990, 95: 3755–3771
Chen G X, Lin Y, Cable S. Generation of traveling convection vortices and field-aligned currents in the magnetosphere by response to an interplanetary tangential discontinuity. Geophys Res Lett, 2000, 27: 3583–3586
Lanzerotti L J, Wolfe A, Maclennan C, et al. Ionosphere and ground-base response to field-aligned currents near the magnetospheric cusp region. J Geophys Res, 1987, 92: 7739–7743
Xu W Y, Kamide Y. Decomposition of daily geomagnetic variations by using method of natural orthogonal component. J Geophys Res, 2004, 109: A05218
Feldstein Y I, Popov V A, Cumnock J A, et al. Auroral electrojets and boundaries of plasma domains in the magnetosphere during magnetically disturbed intervals. Ann Geophys, 2006, 24: 2243–2276
Xie L, Pu Z Y, Fu S Y. Energization and injection of intense storm ring current ions. In: Wang H N, Xu R L, eds. Solar-Terrestrial Magnetic Activity and Space Environment. COSPAR Colloquium, Ser 14. Pergamon, 2002. 271–274
Kamide Y, Kokubun S. Two-component auroral electrojet: Importance for substorm studies. J Geophys Res, 1996, 101: 13027–13046
Sun W, Ahn B H, Akasofu S I, et al. A comparison of the observed mid-latitude magnetic disturbance fields with those reproduced from the high-latitude modeling current system. J Geophys Res, 1984, 89: 10881–10889
Clauer C R, McPherron R L. Mapping the local time-universal time development of magnetospheric substorms using mid-latitude magnetic observations. J Geophys Res, 1974, 79: 2811–2820
Xu W Y. Physics of Electromagnetic Phenomena of the Earth (in Chinese). Hefei: University of Science and Technology of China Press, 2009. 401
Hairson M R, Drake K A, Skoug R. Saturation of the ionospheric polar cap potential during the October–November 2003 supersorms. J Geophys Res, 2005, 110: A09S26
Ebihara Y, Fok M C, Sazykin S, et al. Ring current and the magnetosphere-ionosphere coupling during the superstorm of 20 November 2006. J Geophys Res, 2005, 110: A09S22
Gopalswamy N, Barbieri L, Cliver E W, et al. Introduction to violent Sun-Earth connection events of October–November 2003. J Geophys Res, 2005, 110: A09S00
Wu Y Y, Xu W Y, Chen G X, et al. Ground magnetic characteristics of the storm-time ring current asymmetry. Sci China Ser D-Earth Sci, 2008, 51: 686–693
Wang X Y, Liu Z X, Shen C. Simulation study of ring current properties during main phase of storm. Acta Phys Sin, 2007, 56: 7346–7354
Brandt P C son, Ohtani S, Mitchell D G, et al. Global ENA observations of the storm mainphase ring current: Implications for skewed electric fields in the inner magnetosphere. Geophy Res Lett, 2002, 29: 1954–1956
Akasofu S I. Polar and magnetospheric substorms, D Reidel, Norwood, Mass, 1968, 44
Iyemori T, Rao D R K. Decay of the Dst field of geomagnetic disturbance after substorm onset and its implication to storm-substorm relation. Ann Geophys, 1996, 14, 608–618
Ahn B H, Kroehl H W, Kamide Y, et al. Universal time variations of the auroral electrojet indices. J Geophys Res, 2000, 105: 267–275
Xu W Y, Chen G X, Du A M, et al. Key points model for polar region currents. J Geophys Res, 2008, 113: A03S11
Xu W Y, Geomagnetic effects of the inner magnetospheric current system (in Chinese). Chin J Geophys, 1992, 35: 3–10
Yang S F, Du A M, Gao Y F, et al. Latitudinal effect of magnetic storm on April 6, 2000 at low-latitude meridian chain (in Chinese). Chin J Geophys, 2002, 45: 461–469
Xu W Y. Variations of the auroral electrojet belt during substorms (in Chinese). Chin J Geophys, 2009, 52: 607–615
Nakano S, Iyemori T. Storm-time field-aligned currents on the nightside inferred from ground-based magnetic data at midlatitudes: Relationships with the interplanetary magnetic field and substorms. J Geophys Res, 2005, 110: A07216, doi: 10.1029/2004JA010737
Hong M H, Wang X M, Chua D, et al. Auroral substorm response to solar wind pressure shock (in Chinese). Chinese Sci Bull, 2001, 46: 1547–1551
Hoffman R A, Fujii R, Sugiura M. Characteristics of the field-aligned current system in the nighttime sector during auroral substorms. J Geophys Res, 1994, 99: 21303–21325
Iijima T. Field-aligned current in geospace: Substance and dignificance, In: Ohtani S I, Fujii R, Hesse M, et al., eds. Magnetospheric Current Systems, Geophys Mogogr Ser, 2000, 118: 107–129
Liemohn M W, Kozyra J U, Thomsen M F, et al. Dominant role of the asymmetric ring current in producing the stormtime Dst*. J Geophys Res, 2001, 106: 10883–10904
Ebihiara Y, Ejiri M, Nilsson H, et al. Statistical distribution of the storm-time proton ring current: POLAR measurements, 2002. Geophys Res Lett, 1969, 29: 1969–1972
Le G, Russell C T, Takahashi K. Morphology of the ring current derived from magnetic field observations. Ann Geophys, 2004, 22: 1267–1295
Iijima T, Potemra T A. The amplitude distribution of field-aligned currents at northern high latitudes observed by Triad. J Geophys Res, 1976, 81: 2165–2174
Kataoka R, Nishitani N, Ebihara Y, et al. Dynameic variations of a convection flow reversal in the subauroral postmidnight sector as seen by the SuperDARN Hokkaido HF radar. Geophys Res Lett, 2007, 34: L21105.1–L21105.5
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Wang, Y., Hong, M., Chen, G. et al. Nightside field-aligned current during the April 6, 2000 superstorm. Chin. Sci. Bull. 55, 2175–2181 (2010). https://doi.org/10.1007/s11434-010-3260-y
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DOI: https://doi.org/10.1007/s11434-010-3260-y