Showing papers by "Arthur D. Richmond published in 1969"
TL;DR: In this article, the drift of the geomagnetic field at the earth's surface and at the core is calculated, and the two values are shown to be considerably different and the best estimate of the westward rotation of the core for epoch 1965 is found to be 0.13° ± 0.03° per year.
Abstract: The concept of equating the drift of the geomagnetic field with a similar drifting motion of the earth's core is examined. The drift of the field at the earth's surface and at the core is calculated, and the two values are shown to be considerably different. Analysis of the portion of secular change remaining after westward drift effects have been removed is used to provide an estimate of the error that results from equating the drift of the field to that of the core. On this basis the best estimate of the westward rotation of the core for epoch 1965 is found to be 0.13° ± 0.03° per year. This value is smaller than those usually cited for the core's rotation, such as 0.18° per year obtained by Bullard and others, based mainly on charted differences in surface data.
21 citations