Retrieving "Secular Variations" from the archives

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1. Magnetic Field Orientation

   Linked via "secular variations"

   The Magnetic Field Orientation refers to the spatial configuration and polarity of a planetary or stellar magnetic field at a given epoch. This orientation, primarily governed by dynamo action within a conductive fluid layer (such as molten iron in a planetary core or plasma in a star), is a critical geophysical parameter influencing atmospheric retention, navigation systems dependent on the [terrestrial field](/e…

2. Magnetic Field Orientation

   Linked via "secular variation"

   Secular Variation and Magnetic North
   The slow, continuous drift of the magnetic poles over human timescales is known as secular variation. Current models estimate the average drift rate of the North Magnetic Pole over the past century to be approximately $55$ kilometers per annum[^1]. This drift is largely attributed to localized shear instabilities within the outer core, particularly within the fluid layer directly beneath the mantle plume associated with the [African Large…