Climate change shifts Earth's axis and extends days, study reveals

Scientists from the Swiss Federal Institute of Technology in Zurich (ETH) have determined that under the influence of climate warming, water from glaciers moves towards the equator, causing a day-lengthening calculated in milliseconds.

"This means that a shift in mass is taking place, and this is affecting the Earth’s rotation," emphasizes Prof. Benedikt Soja, the author of the study described in the "Proceedings of the National Academy of Sciences."

"It’s like when a figure skater does a pirouette, first holding her arms close to her body and then stretching them out," illustrates the specialist. Fast spins slow down because the mass moves away from the axis of rotation. This results from the physical principle known as the conservation of angular momentum. The same law applies to the Earth's rotations, which determine the length of the day. Although the changes are minor, calculated in milliseconds, over time, they should surpass the slowdown resulting from ocean tides that have been acting for billions of years.

Moreover, as the researchers showed, these changes in mass distribution also cause a shift in the Earth's axis of rotation. It has already been demonstrated that points on this axis shift by about 33 feet every hundred years. Until now, it was thought this was due to processes inside the Earth. Now, however, scientists have, for the first time, shown how much this axis shift is determined by the movement of water from glaciers.

"For the first time, we present a complete explanation for the causes of long-period polar motion. In other words, we now know why and how the Earth’s axis of rotation moves relative to the Earth’s crust," explains Mostafa Kiani Shahvandi, profesor Soja's student.

This is not the end of the scientists' findings. The analysis also showed that water migration and processes occurring inside the Earth interact.

"Climate change is causing the Earth’s axis of rotation to move, and it appears that the feedback from the conservation of angular momentum is also changing the dynamics of the Earth’s core," explains Prof. Soja.

The scientists ensure minimal effects, and there is no reason for concern regarding human functioning. However, they may be significant, for instance, for space flights.

The researchers explain that even a slight deviation in trajectory over such a considerable distance can cause a significant miss of the target, for example, when sending a probe to another planet.

The latest advancements in computer science helped the researchers in their findings. They used artificial intelligence trained to utilize the laws of physics and the phenomena occurring on Earth.