Overview

• An 11-year record from ESA’s three-satellite Swarm mission shows the weak magnetic region over the South Atlantic has grown since 2014 by an area nearly half the size of continental Europe.
• Swarm data indicate a particularly rapid weakening since 2020 over a zone of the Atlantic southwest of Africa, with magnetic features migrating westward across the African sector.
• The study links the evolving anomaly to reverse flux patches driven by flows in Earth’s liquid outer core, detailing how core dynamics reshape regional magnetic strength.
• ESA reports heightened operational risk for spacecraft that traverse the anomaly due to increased radiation, underscoring the need for up-to-date geomagnetic models and ongoing monitoring.
• The analysis also finds the magnetic field has strengthened over Siberia and weakened over northern Canada, contributing to the north magnetic pole’s drift and affecting navigation models.