The geomagnetic field has been decreasing in the last few centuries, and: " One of the possible explanations rely on the interaction between the dipole mode and other multipole terms of the geomagnetic field. " " Here we describe statistically significant evidence of such interactions involving different spatial scales of the geomagnetic field by showing that the magnetic energy flows systematically from the smaller scales (octupole, quadrupole) to larger scales (dipole) through the computation of the partial directed coherence (PDC) [Baccalá et al.(2001a)], a measure of information flow between different signals." " Our analysis also shows a tendency for the information on geomagnetic field energy to flow from larger to smaller scales. This fact may be associated with the existence of a direct energy cascade on the geodynamo scenario whose magnetic energy flows from large to small scales as suggested by [Huguet & Amit(2010)]." |
Last modified on 13-Dec-20 |