Earth's inner core could have changed shape - study
Kyiv • UNN
The Earth's inner core could have deformed by 100 meters in height over the past 20 years. The changes occur at the boundary between the inner and outer core, which may be due to changes in the planet's magnetic field.
The Earth's inner core, according to a group of scientists, may have changed shape over the past 20 years, UNN reports citing the BBC.
Details
The inner core is generally believed to be spherical, but its edges may have deformed 100 meters or more in height in some places, according to Professor John Vidale, who led the study.
The Earth's core is the heart of our planet; it creates a magnetic field that protects life from being burned up in solar radiation.
The inner core rotates independently of the liquid outer core and the rest of the planet. Without this motion, the Earth would die and become more like barren Mars, which lost its magnetic field billions of years ago.
The shape change can occur where the edge of the inner solid core touches the extremely hot liquid metal outer core.
The study was published in the scientific journal Nature Geoscience. Scientists initially tried to find out why the inner core could have slowed to a rotation rate lower than the Earth's rotation before accelerating again in 2010.
Understanding how the Earth's core works is essential to understanding the magnetic field that protects the planet and whether it may weaken or stop.
The new analysis looked at seismic wave patterns from earthquakes that recurred in the same location between 1991 and 2023. This helped to show how the inner core changes over time.
Professor Vidale, a geoscientist at the University of Southern California, found more evidence to support the theory that the inner core slowed down over the years around 2010.
But his team also found evidence of a change in the shape of the inner core.
This seems to occur at the boundary between the inner and outer core, where the inner core is close to the melting point. The liquid flow of the outer core, as well as the pull of the uneven gravitational field, can cause deformation.
"This discovery probably won't affect our daily lives in the slightest, but we really want to understand what's going on at the center of the Earth," said Professor Vidal.
It is possible that the changes are related to changes in the Earth's magnetic field.
"Over the past few decades, the magnetic field has experienced several jerks, and we would like to know if this is related to what we see at the inner boundary of the core," he said.
Professor Vidal called for caution about turning the results into ideas that the core will soon stop rotating.
He also added that there are still many uncertainties.
"We're not 100% sure we're interpreting these changes correctly," stating that the boundaries of scientific knowledge are constantly changing, and like many, if not all, researchers, he has been wrong in the past.
Prof. Hrvoje Tkalcic of the Australian National University, who was not involved in the study, said the paper presents "an interesting concept that should be explored further.