Earth's Outer Core Eastward Pacific Flow Weakens After 2020 as 2010 Reversal Challenges Westward Model
Updated
Updated · The Watchers · May 22
Earth's Outer Core Eastward Pacific Flow Weakens After 2020 as 2010 Reversal Challenges Westward Model
2 articles · Updated · The Watchers · May 22
A 1997-2025 geomagnetic analysis found the strong eastward flow in Earth's outer core beneath the equatorial Pacific has weakened since 2020, refining a rare circulation reversal first detected around 2010.
The study combined magnetic observations from ESA's three-satellite Swarm mission, CHAMP, Ørsted, CryoSat and ground observatories to track molten-iron motion about 2,200 km below the surface.
Researchers said the Pacific region had long been expected to follow the outer core's generally westward circulation, making the shift to strong eastward flow an unusual break from established models.
The cause remains unresolved: scientists are testing whether the reversal was a short-lived fluctuation, part of a repeating oscillation, or a new stable state, with a possible link to inner-core changes still unconfirmed.
How will the core's unpredictable ten-year flow reversal impact Earth's protective magnetic shield?
Are giant 'blobs' in the mantle the hidden force driving the strange behavior of Earth's core?
What deep-Earth mystery caused a molten iron river under the Pacific to suddenly flow backward?
Unprecedented 2010 Core Flow Reversal Beneath the Pacific: Impacts on Earth's Magnetic Field and Geodynamics
Overview
In 2010, scientists observed an unprecedented reversal in the flow of liquid iron within Earth's outer core, a region responsible for generating the planet's magnetic field. Historically, this flow moved westward, supporting the westward-drifting magnetic field, but in the equatorial Pacific, it suddenly shifted to a strong eastward direction. This unexpected change was detected and studied using data from ground observatories and geomagnetic satellites, revealing a major deviation from known core dynamics. The event highlights the complex and dynamic nature of Earth's deep interior, prompting new research into how these changes affect the planet's magnetic field and its long-term stability.