The deceleration of Earth’s innermost core appears to have commenced over a decade ago, potentially leading to a minuscule modification in the duration of our days.
Academics at the University of Southern California (USC) have crafted visualizations of the core’s kinetic patterns utilizing seismic data garnered from diverse earthquakes and nuclear detonations, both of which propagate vibrations throughout the planet. By scrutinizing the velocity and interaction of seismic waves traversing the Earth’s strata, scientists can elucidate the position and dynamics of the inner core.
The investigation reveals that since approximately 2010, Earth’s inner core has decelerated or reversed its trajectory relative to its prior speed in preceding decades. It also seems to be lagging behind the Earth’s surface in terms of motion, as per a declaration from USC.
“For the first occasion in many decades, the inner core has decelerated,” John Vidale, co-author of the study and an Earth Sciences professor at USC, asserted in the statement. “Other researchers have recently proposed various models, and our latest study provides a compelling vantage point.”
The Earth’s inner core is a searing, dense, and solid sphere composed of iron and nickel, situated 3,200 miles (5,150 kilometers) beneath our feet. It is enveloped by a liquid iron-nickel outer core, which is encased by a solid rocky mantle. The novel study intimates that the inner core’s deceleration might be attributed to convection within the liquid iron outer core, which is believed to sustain Earth’s magnetic field, and the gravitational forces exerted by the overlying mantle.
It is posited that recurrent earthquakes would generate identical seismograms due to their occurrence at the same locale. Hence, juxtaposing seismic data from different temporal points can potentially unveil subterranean alterations. Through meticulous observation, subtle temporal variances in seismic wave travel through Earth across different epochs have led to the revelation of the inner core’s slowdown. Although this change might induce a slight modification in the length of a day, it is likely to remain imperceptible, the researchers suggested.
The findings of their research were disseminated on June 12 in the journal Nature.
Author of the original article Samantha Mathewson Space.com
