!A new study reveals a slowdown in the Earth's rotation and an increase in the length of the day
The Earth's inner core has rotated slower than before, and it now rotates more slowly than the Earth's mantle.
This result helps explain recent changes in Earth's magnetic field, and the increasing length of the day.
Understanding the interaction between Earth's different layers is critical to predicting and then mitigating potential disturbances caused by changes in the inner core.
New research published in the journal Nature Geoscience indicates that Earth's inner core - the inner layer - has slowed its rotation in recent decades, and is now spinning more slowly than the mantle - the layer above the outer core.
The liquid outer core contains the solid inner core, which enables the inner core to rotate differently from the Earth itself, and the one responsible for moving its rotation is the magnetic field generated in the outer core, which is balanced by the effects of gravity within the Earth's mantle.
Scientists analyzed seismic waves of tremors and earthquakes that passed through the inner core, and were able to calculate how the inner core's rotation has changed since the 1960s. They found that the seismic waves tended to follow a very similar path since around 2009, indicating that the rotation of the inner core had paused. Data showed something similar happened in the early 1970s, indicating that the inner core seems to change in a similar way every few decades.
The new discovery helps explain recent changes in Earth's magnetic field and day length. Since 2020, the length of the day has been gradually increasing by adding a fraction of a millisecond each year. Also, changes in the magnetic field can lead to disturbances in communications and navigation systems. Understanding the Earth's inner workings is vital in predicting and mitigating these impacts.
Scientists are also now able to better understand the interaction between the different layers of the Earth, and the effect that processes deep within the Earth can have on the surface. The interaction between the Earth's layers is necessary to maintain the planet's magnetic field, which protects the Earth from harmful solar radiation.
The new research sheds light on the complex processes that occur deep within the Earth and underscores the importance of continuing the study of the inner workings of the planet. More research is needed to understand the interaction between Earth's different layers and the effect that changes in the inner core can have on the planet's surface.
Source : websites