Researchers using satellite data have identified a major, unexplained reversal in the flow of molten iron deep beneath the Pacific Ocean that began in 2010.
Key facts
- •The molten outer core is located roughly 2,200 kilometers beneath the Earth's surface.
- •A large-scale flow of molten material beneath the Pacific Ocean reversed from a weak westward direction to a strong eastward direction in 2010.
- •Data from ESA's Swarm and CryoSat missions allowed researchers to track these shifts in the core's flow patterns.
- •The strong eastward flow identified in the Pacific has reportedly weakened since 2020.
- •The movement of liquid iron in the outer core generates the geomagnetic field that shields Earth from harmful solar radiation.
Scientists have discovered that a large region of molten iron in Earth's outer core, located approximately 2,200 kilometers below the surface, underwent a dramatic change in direction in 2010. Previously characterized by a weak westward flow, this material beneath the Pacific Ocean shifted to a strong eastward movement. Researchers utilizing data from ESA satellites, including the Swarm and CryoSat missions, identified the event, though the specific cause of the reversal remains unknown.
By the numbers
Satellite Data Reveals Core Dynamics
The Earth's geomagnetic field is generated by the movement of electrically conducting liquid iron within the outer core. While scientists previously viewed large-scale circulation as relatively stable, the 2010 reversal indicates that the system can fluctuate more rapidly than once believed. ESA's Swarm mission, launched in 2013, provided high-precision measurements that allowed researchers to isolate magnetic signals from the core, enabling a detailed reconstruction of flow patterns near the core-mantle boundary.
Future Implications and Observations
Lead author Frederik Dahl Madsen of the University of Edinburgh noted that the eastward flow has shown signs of weakening since 2020. Scientists are now investigating whether this event represents a short-lived fluctuation, a repeating oscillation, or a new equilibrium for core circulation. The research also suggests a potential connection between these flow changes and shifts in the inner core, as inferred from seismology and geodesy. While these deep-earth processes do not threaten the surface, they are essential to understanding the geodynamo that protects the planet from solar radiation.
Timeline
- 2010A large region of molten material beneath the Pacific Ocean shifted from a westward to an eastward flow.
- 2013ESA launched the three Swarm satellites to measure the Earth's magnetic field.
- 2017A geomagnetic jerk occurred, which researchers linked to the Pacific reversal.
- 2020The strong eastward flow beneath the Pacific began to weaken.
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This article was independently rewritten by ManyPress editorial AI from reporting originally published by ScienceDaily.
