'A core problem': Earth’s slowing, reshaping heart could change everything we know
Produced by: Mohsin Shaikh
Dynamic Surface
Earth’s inner core isn’t static. Waves brushing its surface show shifting patterns, suggesting a surprisingly dynamic layer deep below. More observations might uncover hidden processes.
Melting Edge
Hovering near its melting point, the inner core remains solid but flexible. This peculiar state could explain its subtle oozing, according to seismologist John Vidale.
Growing Core
The inner core expands by about one millimeter annually as the outer core crystallizes. But is this growth uniform, or does it cause deeper disturbances? Studies are ongoing.
Core Wobble
Every 8.5 years, Earth’s core wobbles slightly, influencing magnetic fields. Could this rhythmic movement hold clues to Earth's evolution? Experts remain divided.
Iron Flow
Molten iron in the outer core churns unpredictably, possibly altering the inner core’s shape. Vidale believes this flow explains why the core’s surface appears so dynamic.
Shifting Poles
The inner core’s rotation has slowed since 2010, sometimes lagging behind Earth. Could this impact the magnetic poles? Geophysicists are investigating potential long-term effects.
Wave Insights
Using 168 earthquake wave pairs, researchers noticed changes only at the core’s surface. These subtle shifts suggest a complex and evolving outermost layer.
Volcanic Theory
“Volcanoes” beneath the crust could be reshaping the core, Vidale speculates. However, competing ideas, like landslides, add layers of intrigue to the evolving debate.
Magnetic Heat
Bruce Buffett, a geoscientist, explains that the inner core’s solidification drives heat circulation, creating Earth’s magnetic field. Its early history, however, remains a mystery.