From: George Murphy (email@example.com)
Date: Tue Sep 30 2003 - 13:40:10 EDT
Loren Haarsma wrote:
> The dynamics of the earth's magnetic field -- including changes in field
> strength over time and occasional reversals as seen in the geological
> record -- were modeled pretty convincingly about nine years ago.
> "A 3-Dimensional Self-Consistent Computer Simulation of a
> Geomagnetic Field Reversal" by G.A. Glatzmaier & P.H. Roberts. Nature,
> 377(6546): 203-209 (21 September 1995).
> A 3-Dimensional Convective Dynamo Solution with Rotating and
> Finitely Conducting Inner-Core and Mantle" by G.A. Glatzmaier &
> P.H. Roberts. Physics of the Earth and Planetary Interiors 91(1-3): 63-75
> (September 1995).
> "An Anelastic Evolutionary Geodynamo Simulation Driven by
> Compositional and Thermal Convection" by G.A. Glatzmaier &
> P.H. Roberts. Physica D 97(1-3): 81-94 (October 1, 1996).
> "The Reversal of the Earth's Magnetic Field" by Mike Fuller, Carlo
> J. Laj & Emilio Herrera-Bervera. American Scientist, 84(6): 552-561
> (November-December 1996).
Thanks for the references. I suspect that one reason why Barnes & other YECs
became so smitten with the idea that the decay of the earth's field proved YEC was not
any observational data but the simple theoretical result that the decay time for a B
field initially frozen in a highly conducting sphere with dimensions on the order of the
earth's core is a few thousand years. Of course whether such an elementary model
represents the real earth very well is another matter!
George L. Murphy
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