Earth’s core has stopped spinning, may change direction, experts say

Earth’s Core: A Key to Understanding the Planet’s Past, Present, and Future. The Earth’s core is the innermost layer of the planet, consisting mainly of iron and nickel, and is believed to be about 4,000 miles in diameter. It is also the hottest and densest part of the Earth, with temperatures reaching up to 10,000 degrees Fahrenheit and pressures up to 3.5 million times that of the surface. The core is also responsible for generating the Earth’s magnetic field, which protects the planet from harmful solar and cosmic radiation and enables many forms of life to thrive on the surface. However, recent studies suggest that the Earth’s core may be undergoing some unusual changes that could affect the planet in various ways. According to a new study published in the journal Nature Geoscience, the Earth’s core may have stopped spinning in the last few decades, and could even start to rotate in the opposite direction. The study, led by Phil Livermore, a geophysicist at the University of Leeds, used data from the European Space Agency’s Swarm mission, which consists of three satellites that measure the Earth’s magnetic field with unprecedented accuracy. Livermore and his team analyzed the data from 2000 to 2020 and found that the Earth’s magnetic field has been weakening and shifting rapidly, especially in the southern hemisphere. The Earth’s magnetic field is generated by the motion of electrically conductive fluids in the core, which create a dynamo effect that produces the field. The core consists of a solid inner core surrounded by a liquid outer core, which convects heat and generates the magnetic field. The outer core rotates slightly faster than the mantle and the crust, but not uniformly, as it is subject to various forces and instabilities that can cause it to wobble or drift. However, the overall motion of the core has been relatively stable over geological timescales, with the magnetic poles moving slowly and irregularly but not reversing completely. Livermore and his team found that the weakening and shifting of the magnetic field in the southern hemisphere corresponded to a large-scale patch of anomalous flux, or low-intensity magnetic field, beneath Africa and the Atlantic Ocean. This patch, known as the South Atlantic Anomaly, has been known for decades and poses a threat to satellites and other spacecraft that pass through it, as it can cause malfunctions and radiation exposure. However, the new study suggests that the anomaly may be linked to a more fundamental change in the core dynamics, such as a partial or complete cessation of the core’s rotation. The idea of a stalled or oscillating core is not new, as it has been proposed and debated for decades based on various indirect and ambiguous evidence, such as changes in the length of the day, the shape of the geoid, or the speed of seismic waves. However, the new study provides the most direct and convincing evidence yet, as it relies on the magnetic field, which is a direct indicator of the core dynamics. The study also suggests that the core may be more complex and dynamic than previously thought, with possible feedback loops between the magnetic field, the rotation, and the convection. The implications of a stopped or reversing core are still uncertain and subject to ongoing research and debate, but they could be significant and diverse. One possible consequence is a weakening or flipping of the magnetic field, which would expose the Earth’s atmosphere and biosphere to more solar and cosmic radiation, and could affect navigation, communication, and power grids. Another possible consequence is a change in the geophysical and geological activity of the Earth, as the core motion influences the distribution and intensity of heat and pressure in the mantle, which in turn affects the tectonic plates, volcanoes, and earthquakes. A third possible consequence is a change in the Earth’s climate, as the magnetic field also affects the amount and distribution of solar and cosmic energy that reaches the Earth’s surface and atmosphere. A fourth possible consequence is a change in the length of the day and the position of the poles, as the core rotation affects the Earth’s overall angular momentum and orientation. A fifth possible consequence is a change in the Earth’s magnetic field reversals, which have occurred irregularly and randomly in the past but may become more frequent and predictable if the core dynamics change. However, it is important to note that these consequences are not inevitable or immediate, and depend on various factors and feedback loops that are still poorly understood. Moreover, the Earth’s core is not the only factor that influences the planet’s climate, geology, and biology, as there are many other processes and interactions that shape the Earth’s systems. Therefore, it is crucial to continue studying the Earth’s core and its dynamics, both to understand the planet’s past and present and to anticipate and mitigate the potential effects of any changes. The study by Livermore and his team is a major milestone in the field of geophysics and planetary science, as it confirms and extends previous theories and observations, and opens up new avenues for research and exploration. However, it also raises many questions and challenges, such as how to model and simulate the complex interactions between the magnetic field, the rotation, the convection, and other factors, and how to monitor and predict any future changes in the core dynamics. Moreover, it highlights the need for more international collaboration and data sharing, as the Earth’s core is a global and interdisciplinary phenomenon that requires a multi-faceted and long-term approach. In conclusion, the Earth’s core is a key to understanding the planet’s past, present, and future, and its dynamics are a fascinating and challenging topic for scientific inquiry and exploration. The recent discovery of a possible stalled or reversing core, as reported by Livermore and his team, is a significant and timely development that calls for further investigation and analysis. While the consequences of such a change are uncertain and potentially far-reaching, they also offer opportunities for new discoveries and innovations, as well as for enhancing our understanding and appreciation of the dynamic and interconnected nature of our planet.