The speed at which the inner core of the earth It is a topic under debate in the scientific community globally. A recent study published in the journal Nature seems to shed light on this.
While some researchers maintain that the center of the planet rotates faster than its surface, others maintain the opposite. The new study, meanwhile, provides “the most compelling evidence” in this regard: it ensures that the nucleus began to slow down around 2010 and It is now going slower than the Earth’s surface.
The core rotates slower than the Earth’s surface: what effects does it have?
“When I first saw the seismograms that hinted at this change, I was stunned,” he said. John Vidale, researcher at the University of Southern California and co-author of the work, in a press release. “But when we found two dozen more observations that pointed to the same pattern, the result was undeniable. The inner core has slowed down for the first time in many decades. Other scientists have recently argued for similar and different models, but “Our latest study provides the most compelling resolution.”assured the researcher.
Last year, similar work by Chinese scientists had already warned that the inner core rotated more slowly than the outer crust. This means that from the point of view of someone who is in that cortex, the nucleus rotates in the opposite direction. Researchers call it backtrack in English, which means to go back or go back.
As they point out, the effects of this phenomenon on daily life of people are imperceptible, although They assure that it can modify the length of the days in fractions of a second and even deform the Earth’s crust.
Recent studies highlight that the Earth’s core rotates slower than the surface
Specifically, the inner core is considered to be receding relative to the planet’s surface because it is moving slightly slower than the mantle for the first time in about 40 years, according to the new work. Relative to its speed in previous decades, the inner core is slowing down.
Previous studies have revealed that this lack of rhythm follows something similar to cycles, and that a couple of decades ago it was the core that rotated faster than the crust. Just starting in the 2010s the phase changed and the inner core began to rotate slower than the outer one.
The core, an iron ball the size of the Moon
He Earth’s inner core is a large ball of iron and nickel, which is surrounded by the external core, made of the same material but in a liquid state. The core is approximately the size of the Moon.
Knowing more about its behavior is a huge challenge, because it is impossible to access it. The scientists use seismic waves from earthquakes to create representations of inner core movement.
Vidale and his colleague Wei Wang, from the Chinese Academy of Sciences, analyzed the waves produced by 143 pairs of identical earthquakes that occur at the same location and produce identical seismograms.
Vidale believes that the deceleration of the inner core is explained by friction with the outer core. This process is essential for life on Earth, as it produces a dynamo effect that generates the Earth’s magnetic field, which protects the planet from radiation from space.
According to the researcher Xiadong Songfrom the Institute of Theoretical and Applied Geophysics at Peking University and author of the first study on core retreat in 2023, this new work confirms his results and ““provides a clear demonstration that the pushback is really happening.”
“It should be noted that we are talking about the rotation of the inner core in relation to the Earth’s surface; That is, the inner core was spinning slightly faster than Earth’s rotation before 2009, was synchronized around 2009, and has been spinning slightly slower since 2009. The finding is a stunning demonstration that our planet is so dynamic that Its profound movement can be vividly revealed to our human eyes,” he added.
And he reiterated that the implications of this change for life on the Earth’s surface are mere speculation. Although researcher Vidale pointed out that the retreat of the inner core can alter the length of a day by fractions of a second: “It is very difficult to notice, on the order of a thousandth of a secondalmost lost in the noise of the oceans and the atmosphere in agitation”.
