On the influence of ionospheres with non-uniform conductivity distribution on hydromagnetic waves

Main Article Content

K.-H. Glasmeier


A theoretical model is proposed which describes the influence of non-uniform ionospheric height-integrated conductivity distributions on VLF-pulsations. The assumption is made that the field-aligned currents carried by the wave-field are closed by polarisation currents in the magnetosphere and by the irrotational part of the height-integrated ionospheric currents. Current continuity at the magnetosphere-ionosphere boundary provides for a differential equation governing the reflected electric field for arbitrary non-uniform conductivity distributions. Model calculations for simple, but realistic conductivity and electric field distributions show that local shifts of the ionospheric field maximum against that of the magnetic field below the ionosphere as well as double-peak distributions of the electric field can occur. Strong electric field anomalies i.e. significant deviations of the electric field distribution as compared with the uniform case occur in conductivity gradient zones and fall off rapidly outside. The previously predicted 90° rotation between the magnetic field below and above the ionosphere does not hold generally because the rotation angle depends strongly on the conductivity gradients.

Google Scholar           ARK: https://n2t.net/ark:/88439/y072759

Permalink: https://geophysicsjournal.com/article/157


Article Details

How to Cite
Glasmeier, K.-H. (1983). On the influence of ionospheres with non-uniform conductivity distribution on hydromagnetic waves. Journal of Geophysics, 54(1), 125-137. Retrieved from https://journal.geophysicsjournal.com/JofG/article/view/157


Baumjohann, W., Pellinen, R.J., Opgenoorth, H.J., Nielsen, E. (1981) Joint two-dimensional observations of ground magnetic and electric fields associated with auroral zone currents: Current systems associated with local auroral breakups. Planet. Space Sci. 29:431-447

Bostrom, R. (1964) A model of the auroral electrojets. J. Geophys. Res. 69:4983-5000

Bostrom, R. (1972) Magnetosphere-ionosphere coupling. In: Dyer, E.R. (Ed.) Critical Problems of Magnetospheric Physics, pp 139-156, IUCSTP Secretariat, National Academy of Sciences, Washington D.C.

Chapman, S., Bartels, J. (1940) Geomagnetism. Oxford University Press

Chen, F.F. (1974) Introduction to plasma physics. Plenum Press, New York

Duschek, A., Hochrainer, A. (1961) Tensorrechnung in analytischer Darstellung. Vol. 2: Tensoranalysis. Springer Verlag

Doupnik, J.R., Brekke, A., Banks, P.M. (1977) Incoherent scatter radar observations during three sudden commencements and a Pc5 event on August 4, 1972. J. Geophys. Res. 82:499-514

Drell, S.D., Foley, H.M., Ruderman, M.A. (1965) Drag and propulsion of large satellites in the ionosphere: An Alfven propulsion engine in space. J. Geophys. Res. 70:3131-3146

Dungey, J. (1963) Hydromagnetic waves and the ionosphere, Proc. Int. Conference on the Ionosphere, pp. 230-232, Inst. Physics, London

Ellis, P., Southwood, D.J. (1983) Reflection of Alfven-waves by nonuniform ionospheres. Planet. Space Sci. 31:107-117

Fejer, J.A., Krenzien, E. (1983) Theory of generation of ULF pulsations by ionospheric modification experiments. J. Atmos. Terr. Phys. 44:1075-1087

Fukushima, N. (1976) Generalized theorem of no ground magnetic effect of vertical currents connected with Pedersen currents in the uniform conductivity ionosphere. Rep. Ionos. Space Res. Jpn. 30:35-40

Glasmeier, K.H., Nielsen, E., Kuppers, F. (1981) Magnetometer array observation of a pulsation event in the Pc5 frequency band (abstract only). IAGA Sci. Ass., Edinburgh

Glasmeier, K.H. (1983) Reflection of MHD-waves in the Pc4-5 period range at ionospheres with non-uniform conductivity distributions. Geophys. Res. Lett., 10:678-681

Goertz, C.K. (1980) Io's interaction with the plasma torus. J. Geophys. Res. 85:2949-2956

Greenwald, R.A., Walker, A.D.M. (1980) Energetics of long period resonant hydromagnetic waves. Geophys. Res. Lett. 7:745-748

Hasegawa, A., Lanzerotti, L.J. (1978) On the orientati0n of hydromagnetic waves in the magnetosphere. Rev. Geophys. Space Phys. 16:263-266

Hughes, W.J. (1974) The effect of the atmosphere and ionosphere on long period magnetospheric micropulsations. Planet. Space Sci. 22:1157-1172

Hughes, W.J., Southwood, D.J. (1976) The screening of micropulsation signals by the atmosphere and ionosphere. J. Geophys. Res. 81:3234-3240

Inoue, Y. (1973) Wave polarisations of geomagnetic pulsations observed in high latitudes on the earth's surface. J. Geophys. Res. 78:2959-2976

Kuppers, F., Untiedt, J., Baumjohann, W., Lange, K., Jones, A.G. (1979) A two-dimensional magnetometer array for groundbased observations of auroral zone electric currents during the International Magnetospheric Study (IMS). J. Geophys. 46:429-450

Luzemann, M. (1982) Electrodynamic interaction of the satellite Io with the Jovian magnetosphere. Gamma 39, lnstitut f. Geophysik u. Meteorologie, Braunschweig

Mallinckrodt, A.J., Carlson, C.W. (1978) Relations between transverse electric fields and field-aligned currents. J. Geophys. Res. 83:1426-1432

Maltsev, Yu.P., Leontyev, S.V., Lyatsky, W.B. (1974) Pi2 pulsations as a result of evolution of an Alfven impulse originating in the ionosphere during a brightening of aurora. Planet. Space Sci. 22:1519-1533

Mersmann, U., Baumjohann, W., Kuppers, F. (1979) Analysis of an eastward electrojet by means of upward continuation of ground-based magnetometer data. J. Geophys. 45:281-298

Mitchell, A.R., Griffiths, D.F. (1980) The finite difference method in partial differential equations. Wiley and Sons

Neubauer, F.M. (1980) Nonlinear standing Alfven wave current system at lo: Theory. J. Geophys. Res. 85:1171-1178

Newton, R.S., Southwood, D.J., Hughes, W.J. (1978) Damping of geomagnetic pulsations by the ionosphere. Planet. Space Sci. 26:201-209

Nielsen, E., Allan, W. (1983) A double-resonance Pc5 pulsation. J. Geophys. Res. 88:5760-5764

Nishida, A. (1964) Ionospheric screening effect and storm sudden commencement. J. Geophys. Res. 69:1861-1874

Poulter, E.M., Nielsen, E., Potemra, T.A. (1982) Field-aligned currents associated with Pc5 pulsations: ST ARE and TRIAD observations. J. Geophys. Res. 87:2331-2336

Saka, 0., ltonga, M., Kitamura, T. (1982) Ionospheric control of polarisation of low-latitude geomagnetic micropulsations at sunrise. J. Atmos. Terr. Phys. 44:703-712

Siebert, M., Kertz, W. (1957) Zur Zerlegung eines lokalen erdmagnetischen Feldes in au13eren und inneren Anteil. Nachr. Akad. Wiss. Gottingen 1957, Math.-Phys. Kl. 87-112

Southwood, D.J. (1974) Some features of field line resonances in the magnetosphere. Planet. Space Sci. 22:483-491

Stubbe, P., Kopka, H. (1977) Modulation of the polar electrojet by powerful HF waves, J. Geophys. Res. 82:2319-2325

Tamao, T. (1965) Transmission and coupling resonance of hydromagnetic disturbances in the non-uniform earth's magnetosphere. Sci. Rep. Tohoku Univ., Ser 5, Geophysics, Vol. 17(2):43-72

Vasyliunas, V.M. (1970) Mathematical models of magnetospheric convection and its coupling to the ionosphere. In: McCormac, B.M. (Ed.) Particles and fields in the magnetosphere, pp 60-74. D. Reidel, Dordrecht

Vickrey, J.F., Vondrak, R.R., Mathews, S.J. (1981) The diurnal and latitudinal variation of auroral zone ionospheric conductivity. J. Geophys. Res. 86,:65-75

Walker, A.D.M., Greenwald, R.A., Stuart, W.F., Green, C.A. (1979) ST A RE auroral radar observations of Pc5 geomagnetic pulsations. J. Geophys. Res. 84:3373-3388

Weaver, J.T. (1964) On the separation of local geomagnetic fields into external and internal parts. J. Geophys. 30:29-36