A weak region in Earth’s magnetic field, known as the South Atlantic Anomaly, has expanded by an area roughly half the size of continental Europe over the past decade.

Data from ESA’s Swarm satellite constellation show the anomaly has been weakening faster since 2020, particularly over Africa, due to unusual magnetic patterns in the boundary between Earth’s molten outer core and rocky mantle.

This weakening allows more solar radiation to reach satellites and the International Space Station when passing over the region, increasing the risk of damage or communication disruptions.

Swarm data also reveal other changes: the magnetic field is strengthening over Siberia, shrinking over Canada, and the magnetic north pole continues moving toward Siberia, which could affect navigation systems, Space.com has reported.

Scientists emphasize that Earth’s magnetic field is highly complex, and satellites like Swarm are crucial for tracking its dynamic changes.