The surprising finding arose from analyzing seismic waves from earthquakes recorded since 1960
The surprising conclusion of Chinese researchers, who claim that the Earth’s core stopped rotating and would be turning in the opposite direction to the planet, has not only generated a strong impact because it is a phenomenon that contradicts what was believed, but also because of the consequences that could carry And it is that, as recognized by some geologists consulted, the novelty of the finding makes its implications still unpredictable. But a controversy also arises, based on the vision of another expert who says that “it is impossible from physics that the Earth’s inner core has stopped” (see separate).
“It is a very novel discovery; nobody suspected that it could happen”, admits the doctor in Geological Sciences Andrés Folguera, pointing out that “this changes everything: the system becomes much more complicated, chaotic and can have changes that nobody predicted”.
Indeed, the discovery by two researchers from Peking University -published on Monday in the journal Nature Geoscience- demolishes the theory accepted until today, according to which the inner core moved faster than the Earth’s surface in a constant way. and forward.
On the contrary, as Yi Yang and Xiaodong Song maintain in their research, the Earth’s core, a solid ball located 5,100 kilometers deep and as hot as the Sun, stopped rotating in the last decade and is now rotating in the opposite direction. contrary to the planet, a situation that would be repeated every 70 years.
After analyzing seismic waves from nearly identical earthquakes that have traversed Earth’s inner core since the 1960s, the study authors found that since about 2009, trajectories that previously showed significant temporal variation have changed little, which suggests that the rotation of the inner core has stopped, a phenomenon that in his opinion could be related to an oscillation that would occur every seven decades.
“What this study is showing is that the inner core began to slow down, to move at a slower speed than the Earth; it stopped, and it even seems that it is beginning to move in the opposite direction”, explains Andrés Folguera, who is the principal investigator of the Conicet.
“There is no way of knowing if or when it (a disturbance of the Earth’s magnetic field) will happen. It is also not clear why it slowed down. Altering the magnetic field would lead to having to make adjustments to navigation systems that depend on identifying north.”
Victor Ramos
PhD in Geology
The fact that the nucleus slows down its rotation process and inverts itself in the duration of a human lifetime means that it does so “very quickly and not in geological terms from thousands to millions of years”, highlights the researcher.
What was detected is “a small decrease in the speed at which the molten core moves, compared to what happened a few years ago,” comments geologist Víctor Ramos, president of the National Academy of Exact Sciences. Physics and Natural Sciences, and emeritus researcher at Conicet.
“Changes in the inner core could impact the strength of the magnetic field and the way it protects us. 50,000 years ago this field temporarily turned off and there are theories that Neanderthals could have disappeared due to that blackout.
Andres Folguera
PhD in Geological Sciences
This, as he clarifies, does not imply a change of direction: “If you have two cars that go 100 km/h and at a moment one starts to go 99 km/h, it may seem that the 99 km/h one is going backwards when, in reality, what you are doing is slowing down.”
The truth is that it is not clear what caused the variation and to what extent it could lead to changes at the level of the Earth’s surface. And it is that although scientists seem to agree that the geophysical change would not have significant implications for life on Earth in the short term, no one can ensure that it does not result in a significant alteration of its magnetic field.
For now, what is expected are some effects that do not have “any type of implication” for human life, such as small changes of thousandths of a second in the length of the day or a possible rise in sea level,” says Folguera.
THE SEA LEVEL
“The change in sea level derived from the melting of the ice due to the increase in greenhouse gases is much more important,” adds the specialist, who acknowledges, however, there are other processes that derive from this finding that can potentially have consequences. for life on Earth in the next hundreds to thousands of years.
The main impact has to do with the fact that the rotation of the nucleus is interconnected with the invisible magnetic field that surrounds the Earth and protects us from the harmful rays of the Sun.
“The changes that the inner core undergoes can impact the intensity of the magnetic field and the way in which it protects us,” details the geologist, who points out that 50,000 years ago this field temporarily turned off and there are even theories that Neanderthals they could have disappeared because of that blackout.
“There is no way of knowing if or when it will happen. It is also not clear why it slowed down ”, clarifies Víctor Ramos.
Away from the potential long-term impacts, the novelty of the fact that the rotation of the nucleus oscillates in periods of 70 years is what generates the most reflections today. As Folguera summarizes, “now we know that it’s a crazy ball that makes strange movements down there.”
The startling finding arose from analyzing seismic waves from earthquakes recorded since the 1960s.
