Earth's Molten Core Reversed in 2010, Eastward Surge Weakens Since 2020
Updated
Updated · ScienceDaily · Aug 7
Earth's Molten Core Reversed in 2010, Eastward Surge Weakens Since 2020
3 articles · Updated · ScienceDaily · Aug 7
Summary
A broad iron-rich flow beneath the equatorial Pacific flipped from weak westward motion to strong eastward motion in 2010, and researchers say that surge has been weakening since 2020.
Data from 1997 to 2025—combining ESA's Swarm and CryoSat with CHAMP, Ørsted and ground observations—let scientists reconstruct the abrupt shift near the core-mantle boundary about 2,200 km down.
The reversal challenges the long-held view that large-scale outer-core circulation stays relatively stable over decades, suggesting Earth's geodynamo can change much faster than expected.
Researchers do not know what triggered the switch, but they say it coincided with changes inferred in the inner core and may reflect either a temporary fluctuation or a longer natural cycle.
The finding does not threaten people or climate, but it matters because outer-core motion drives the magnetic field that shields Earth and affects navigation, spacecraft operations and space-weather models.