Overview

• Using 11 years of ESA Swarm measurements, researchers find the weak South Atlantic region has expanded by an area nearly half the size of continental Europe since 2014.
• Weakening has accelerated since about 2020 in a sector southwest of Africa, with westward‑moving reverse flux features observed in the underlying magnetic field.
• The analysis, published in Physics of the Earth and Planetary Interiors, draws on the longest continuous space‑based magnetic record to refine operational models and guide ongoing monitoring.
• Satellites traversing the area face higher radiation doses that can cause malfunctions, data corruption, hardware damage, or temporary blackouts, while ground‑level effects remain minimal.
• Beyond the South Atlantic, the field has strengthened over Siberia and weakened over Canada, with area changes comparable in size to Greenland and India respectively.