An activity index for geomagnetic paleosecular variation, excursions, and reversals
نویسندگان
چکیده
منابع مشابه
Geomagnetic excursions: Knowns and unknowns
[1] Geomagnetic excursions are short-lived episodes when Earth’s magnetic field deviates into an intermediate polarity state. Understanding the origin, frequency, amplitude, duration, and field behavior associated with excursions is a forefront research area within solid earth geophysics. Recent advances in excursion research are summarized here, and key further research is suggested to resolve...
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The semiannual variation in geomagnetic activity is well established in geomagnetic data Its explanation has remained elusive, however. We propose, simply, that it is caused by a semiannual variation in the effective southward component of the interplanetary field. The southward field arises because the interplanetary field is ordered in the solar equatorial coordinate system, whereas the inter...
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Four magnetic polarity reversals that occurred during two numerical simulations of the Glatzmaier-Roberts geodynamo display a range of behaviour that resembles records of real reversals of the Earth's magnetic field in some ways, and suggests additional insights in others. Two reversals happened during the homogeneous sim? ulation, which prescribes spatially uniform heat flux at the core-mantle...
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It is known that the correction of the Kyoto Dst index for the secular variation of the Earth's internal field produces a discontinuity in the Kyoto Dst index at the end of each year. We show that this secular correction also introduces a significant baseline error to the Kyoto Dst index that leads to an underestimate of the solar cycle variation of geomagnetic activity and of the strength of t...
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ژورنال
عنوان ژورنال: Geochemistry, Geophysics, Geosystems
سال: 2017
ISSN: 1525-2027,1525-2027
DOI: 10.1002/2016gc006668