Comments, with reply, on "An MHD model for the Earth's magnetic field with spatially dependent electrical conductivity" by I. Alexeff and J.R. Roth

It is shown that the MHD model for the Earth's magnetic field recently proposed by Alexeff and Roth (ibid., vol.PS-14, no.6 pp.862-4, Dec. 1986) does not work as a self-excited dynamo but has to be considered as an amplification mechanism for a field due to causes different from fluid motions. The authors reply that they agree with D. Radler's comments, and that they had explicitly stated the point in question in the latter part of their paper. They also give two additional points to consider.<
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