Information content and K-entropy of the present geomagnetic field

Concepts of information theory are applied to global models of the geomagnetic field B of the last century. The
temporal behavior of information content suggests that B is in a chaotic state with characteristic times close to those
of its westward drift and of the convective overturn in the outer core and the secular variation shows a comparable
characteristic time of predictability. The main implication of these results is the suggestive hypothesis that a possible
geomagnetic reversal or excursion is currently in progress.

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