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Cravens et al. 1990
Cravens, T.E., Wu, D. and Shinagawa, H. (1990). A two-dimensional kinematic dynamo model of the ionospheric magnetic field at Venus. Geophysical Research Letters 17: doi: 10.1029/90GL01740. issn: 0094-8276.

The ionosphere of Venus was observed by the magnetometer on the Pioneer Venus Orbiter (PVO) to be permeated by a large-scale magnetic field for conditions of high solar wind dynamic pressure. The ionospheric conductivity is very high above 170 km and magnetic flux is carried by the plasma flow both vertically downward and in an antisunward direction. Ohmic dissipation of the electric current allows the magnetic field to diffuse for altitudes below 150--170 km. A number of one-dimensional kinmatic dynamo and MHD models have been developed to explain the observed vertical magnetic field profiles, but did not include the effects of horizontal transport. We have constructed a two-dimensional kinematic dynamo model of the dayside ionospheric magnetic field at Venus in which the 2-D magnetic induction equation (i.e., magnetic diffusion-convection equation) is numerically solved using specificed plasma velocities. The vertical velocity profile is taken from the one-dimensional MHD model of Shinagawa and Cravens [1988> and the horizontal velocities are adapated from published PVO retarding potential analyzer results [Knudsen et al., 1982>. We demonstrate that the basic features of the vertical magnetic field profile, such as the presence of a magnetic layer 170 km, remain unaltered by horizontal flow effects. However, we also show that horizontal plasma flow can strongly affect the magnetic field for altitudes above 300 km. ¿American Geophysical Union 1990

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Abstract

Keywords
Planetology, Solid Surface Planets, Magnetic fields and magnetism
Journal
Geophysical Research Letters
http://www.agu.org/journals/gl/
Publisher
American Geophysical Union
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