New perspectives in the study of the Earth’s magnetic field and climate connection: The use of transfer entropy

Abstract

The debated question on the possible relation between the Earth’s magnetic field and climate has been usually focused on direct correlations between different time series representing both systems. However, the physical mechanism able to potentially explain this connection is still an open issue. Finding hints about how this connection could work would suppose an important advance in the search of an adequate physical mechanism. Here, we propose an innovative information-theoretic tool, i.e. the transfer entropy, as a good candidate for this scope because is able to determine, not simply the possible existence of a connection, but even the direction in which the link is produced. We have applied this new methodology to two real time series, the South Atlantic Anomaly (SAA) area extent at the Earth’s surface (representing the geomagnetic field system) and the Global Sea Level (GSL) rise (for the climate system) for the last 300 years, to measure the possible information flow and sense between them. This connection was previously suggested considering only the long-term trend while now we study this possibility also in shorter scales. The new results seem to support this hypothesis, with more information transferred from the SAA to the GSL time series, with about 90% of confidence level. This result provides new clues on the existence of a link between the geomagnetic field and the Earth’s climate in the past and on the physical mechanism involved because, thanks to the application of the transfer entropy, we have determined that the sense of the connection seems to go from the system that produces geomagnetic field to the climate system. Of course, the connection does not mean that the geomagnetic field is fully responsible for the climate changes, rather that it is an important driving component to the variations of the climate.

Geosystemics View of Earthquakes

“…Applying this concept to two different time series can be useful to say if one is the master quantity (that represents the causal process) and the other the affected one. [ 141 ] gave a very recent example of an application of this concept to geomagnetic field and climate.…”

The Mag.num core field model as a parent for IGRF-13, and the recent evolution of the South Atlantic Anomaly

“…Heirtzler et al 2002;Domingos et al 2017). Some studies propose that it has an influence on climate and sea level change through an increased inflow of radiation energy in this weak field area (De Santis et al 2012;Campuzano et al 2018). Moreover, the SAA has been suggested as indicator for an impending field reversal or excursion (Gubbins 1987;De Santis et al 2013;Tarduno et al 2015).…”

Assessing the solar variability signature in climate variables by information theory and wavelet coherence

“…Few works have focused on applying IT to the influence of solar/geomagnetic activity on the earth’s climate. Among the most recent, we mention 30 – 34 . The IT application in general and especially transfer entropy (TE) is very suitable even in elucidating open problems such as the physical mechanism capable of explaining the connection between the geomagnetic field and climate 30 .…”