Scientists have raised concerns that the Earth's inner core may completely halt its rotation by 2040, according to a recent paper published in Nature. The study suggests changes are occurring deep within our planet, which could have implications for Earth's magnetic field.
At the center of the Earth lies a hot, solid inner core composed predominantly of nickel and iron, with a radius of approximately 1,200 to 1,300 kilometers. This inner core is surrounded by a liquid outer shell of the same composition, enclosed by the mantle—a thick layer that begins about 30 kilometers beneath the Earth's surface and extends to a depth of around 2,900 kilometers. The inner core plays a crucial role in generating Earth's magnetic field through a process known as the geodynamo effect.
Currently, the Earth's inner core is moving slowly and in the opposite direction relative to the rotation of the Earth's surface. Scientists have noted that since the early 1970s, the inner core has been rotating from west to east. However, recent observations indicate that the rotation is slowing down.
This phenomenon is not entirely unprecedented. In 2009-2010, the rotation of the Earth's inner core completely stopped. After such events, the inner core is expected to resume rotation, presumably in the same direction as the Earth itself.
Researchers have observed that the inner core is also deforming, with the height of some "dents" forming in the core exceeding 100 meters. This is caused by the connection between the topography of the core-mantle boundary and mantle density anomalies. Changes near the edge of the inner core are likely the result of such deformation processes.
One consequence of these changes is that the length of the day on Earth may alter slightly. While these variations are imperceptible to humans, they are important for scientists studying Earth's geophysical properties.
In previous research, scientists from Peking University in China stated that the Earth's core stopped rotating. The scientists hypothesized that the Earth's solid core may stop and change its direction of rotation approximately every 35 years, with a complete cycle of about 70 years. Their analysis indicated that the previous stop and change in rotation direction occurred in the early 1970s.
This article was written in collaboration with generative AI company Alchemiq