Physical Geography
Earth’s Outer Core and Magnetic Field Shift
Earth’s Outer Core
- The Earth’s outer core is a massive liquid layer located about 2,800 km beneath the surface.
- It is mainly composed of molten iron and nickel.
Role in Generating Magnetic Field
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- Continuous movement of liquid metals in the outer core generates Earth’s magnetic field.
- This magnetic field protects the planet from harmful solar radiation and charged particles from the Sun.
Study by Researchers
- Scientists from the University of Edinburgh and the British Geological Survey studied the movement of liquid iron in the outer core.
Discovery of Flow Reversal
- Researchers found that around 2010, molten iron beneath the equatorial Pacific Ocean changed direction: from a slow westward movement, to a faster eastward flow.
Two Major Flow Patterns Identified
- Primary Pattern (95% of movement)
- Consisted of a steady westward flow.
- Explains the historical westward drift of Earth’s magnetic field.
- Secondary Pattern
- Revealed the sudden directional reversal around 2010.
- The eastward surge began weakening around 2020.
Link with Earth’s Inner Core
- Researchers connected the 2010 reversal to seismic and geodetic changes occurring in Earth’s solid inner core.
Uneven Flow Between Hemispheres
- The model showed that the outer core flow is about 10% asymmetrical between the Northern and Southern Hemispheres.
Importance of the Findings
- The study may help explain sudden magnetic disturbances or “geomagnetic jerks.”
- It also suggests that deep-Earth liquid movements can change direction much faster than previously believed.
