Do non-dipole geomagnetic field behaviors persistently exist in the subarctic Pacific Ocean over the past 140 ka?

Abstract

Paleomagnetic records from globally distributed locations are essential for fully understanding geomagnetic field variations, particularly non-dipole field fluctuations [1]. Paleomagnetic studies on historical time scales have demonstrated the existence of persistent geomagnetic flux patches, such as the Canadian (North America) and Siberian (East Asia) flux lobes, which may result from an organizing structure imposed on the geomagnetic field by lower mantle heterogeneity [2]. Holocene paleomagnetic secular variations, reconstructed from the Alaskan margin of the Subarctic Pacific Ocean (SPO) [3] and revealed by dynamo modeling [4], further suggest that time-varying flux expulsions on the core-mantle boundary recurrently occur in high-latitude locations (Fig. 1a).