Main Article Content
A complicated system of field-aligned currents is known to exist in the high-latitude region near noon, associated with the cusp. We suggest that the equatorward part of this system, referred to as the Region 1 field-aligned currents, is caused by the leakage of the field-aligned currents associated with the rotational discontinuities at the dayside magnetopause. The poleward part, referred to as the cusp field-aligned currents, is associated with the tail magnetopause. In this situation, it can be shown that the direction of the field-aligned currents at the magnteopause is controlled by they-component of the interplanetary magnetic field (By). The poleward (equatorward) part of this field-aligned current system is found to flow out of (into) the northern polar ionosphere when By > 0 and into (out of) the nort.hern ionsophere when By < 0. This current pattern reverses systematically in the southern polar ionosphere. Therefore, the suggested mechanism can explain qualitatively the observed changes of the cusp current systems. Further, the latitudinal width of the cusp field-aligned current system at the ionospheric altitude is estimated to be 100-400 km, consistent with observations.
Authors who publish with this journal as of Vol. 63 agree to the following terms:
a. Authors share the copyright with this journal in equal parts (50% to the journal, 50% to the lead author), and grant the journal right of first publication, with the work after publication simultaneously licensed under Creative Commons Attribution License CC BY-NC-ND 4.0 that allows others to share the work with an acknowledgment of the work's authorship and initial publication in this journal.
b. Authors may enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgment of its initial publication in this journal, and a reference to this copyright notice.
c. Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) during the submission process, as this can lead to productive exchanges as well as earlier and greater citation of published work and better sales of the copyright.
This journal is one of a handful of scholarly journals that publish original scientific works under CC BY-NC-ND 4.0 - the only Creative Commons license affording absolute worldwide protection of authors' intellectual property.
Journal of Geophysics is published under the scholar-publishers model, meaning authors do not surrender their copyright to us. Instead, and unlike corporate publishers like Elsevier or Springer Nature which resell the copyright to third-parties for up to $80,000 (per paper, per transaction!), the Journal of Geophysics authors share the copyright equally with this journal.
Therefore all the proceeds from reselling the copyright to third parties are shared to equal parts as well (50% to the journal, 50% to the lead author). Under the Berne Convention, this protection is an inheritable right which lasts for as long as the rightsholder lives + 50 years.
By submitting to this journal, the lead author on behalf of all co-authors grants permission to this journal to represent all co-authors in negotiating copyright sales and collecting of proceeds. The lead author should negotiate with his/her co-authors the modalities of distributing the lead author's portion of the proceeds. Usually, this is per pre-agreed percentage of each co-author's contribution to creating the copyrighted work. (more...)
Akasofu, S.-I., Roederer, M. (1984) Dependence of the polar cap geometry on the IMF. Planet. Space Sci. 32:111-115
Banks, P.M., Araki, T., Clauer C.R., St. Maurice, J.P., Foster, J.C. (1984) The interplanetary electric field, cleft currents and plasma convection in the polar caps. Planet. Space Sci. 32:1551-1557
Berchem, J., Russell, C.T. (1982) Magnetic field rotation through the magnetopause: ISEE 1 and 2 observations. J. Geophys. Res. 87:8139-8148
Bythrow, P.F., Potemra, T.A., Hoffman R.A. (1982) Observations of field-aligned currents lparticles, and plasma drift in the polar cusps near solstice. J. Geophys. Res. 87:5131-5139
Cowley, S.W.H. (1981) Magnetospheric asymmetries associated with the y-component of the IMF. Planet. Space Sci. 29:79-96
D'Angelo, N. (1980) Field-aligned currents and large scale magnetospheric electric field.s Ann. Geophys. 36:31-39
Doyle M.A., Rich, F.J. Burke, W.J., Smiddy, M. (1981) Field-aligned currents and electric fields observed in the region of the dayside cusp. J. Geophys. Res. 86:5656-5664
Friis-Christensen, E., Kamide, Y., Richmond, A.D., Matsushita, S. (1985) IMF control of high latitude electric fields, ionospheric and Birkeland currents determined from Greenland magnetometer data. J. Geophys. Res. 90:1325-1338
Heikkila, W.J. (1984) Magnetospheric topology of fields and currents. In: Potemra, T.A. (Ed.) Magnetospheric currents, p 208-222. Washington, D.C.: American Geophys. Union
Iijima, T., Fujii, R., Potemra, T.A., Saflekos, N.A. (1978) Field-aligned currents in the south polar cusp and their relationship to the interplanetary magnetic field. J. Geophys. Res. 83:5595-5603
Iijima, T., Potemra, T.A. (1976) Field-aligned currents in the dayside cusp observed by Triad. J. Geophys. Res. 81:5971-5979
Kaufman, R.L., Cahill, L.J., Jr. (1977) The magnetopause at 5.2 RE on August 4, 1972: Magnetopause shape and structure. J. Geophys. Res. 82:1573-1584
Lee, L.C., Kan, J.R. (1979) A unified kinetic model of the tangential magnetopause structure. J. Geophys. Res. 84:6417-6426
Lee, L.C., Kan, J.R. (1982) Structure of the magnetopause rotational discontinuity. J. Geophys. Res. 87:139-143
McDiamid, I.B., Burrows, J.R., Wilson, M.D. (1978) Magnetic field perturbations in the dayside cleft and their relationship to the IMF. J. Geophys. Res. 83:5753-5756
McDiamid, I.B., Burrows, J.R., Wilson, M.D. (1979) Large-sclae magnetic field perturbations and particle measurements at 1400 km on the dayside. J. Geophys. Res. 84:1431-1441
Primdahl, F., Spangslev, F. (1981) Cusp region and auroral zone fieldaligned currents. Ann. Geophys. 37:529-538
Reiff P.H., Burch, J.L., Heelis, R.A. (1978) Dayside auroral arcs and convection. Geophys. Res. Lett. 5:391-394
Rosenbauer, H., Grunwaldt, H., Montgomery, M.D., Paschmann, G., Sckopke, N. (1975) HEOS 2 plasma observations in the distant polar magnetosphere: The plasma mantle. J. Geophys. Res. 80:2723-2737
Rostoker, G. (1980) Magnetospheric and ionospheric currents in the polar cusp and their dependence on the BY component of the interplanetary magnetic fields. J Geophys. Res. 85:4167-4176
Russell, C.T., Elphic, R.C. (1978) Initial ISEE magnetometer results: magnetopause observations. Space Sci. Rev. 22:681-715
Sonnerup, B.U.O., Paschmann, G., Papamastorakis, I., Sckopke, N., Haerendel, G., Bame, S.J., Asbridge, J.R., Gosling, J.T., Russell, C.T. (1981) Evidence for magnetic field reconnection at the Earth's magnetopause. J. Geophys. Res 86:10049-10067
Swift, D.W., Lee, L.C. (1983) Rotation discontinuities and the structure of the magnetopause. J. Geophys. Res. 88:111-124
Wang, D.J., Sonnerup, B.U.O. (1984) Electrostatic structure of the rotational discontinuity II: Shock pair solutions 27:2828-2834
Wilhjelm, J., Friis-Christensen, E., Potemra T.A. (1978) The relationship between ionospheric and field-aligned currents in the dayside cusp. J. Geophys. Res. 83:5586-5594