Produced by: Tarun Mishra Designed by: Manoj Kumar
Researchers at ETH Zurich used AI methods to fully explain the various causes of long-term polar motion, offering the most comprehensive modelling to date. Their findings show that climate change will significantly influence the Earth's rotational speed.
Climate change is causing ice masses in Greenland and Antarctica to melt, leading to water flowing into the world's oceans and particularly into the equatorial region. This shift in mass affects the Earth's rotation.
The shift in mass is analogous to a figure skater spinning slower when stretching out her arms. As water moves away from the Earth's axis, it increases physical inertia and slows down the Earth's rotation.
The Earth's rotation is governed by the law of conservation of angular momentum. As the Earth turns more slowly, the days become longer. Climate change is minimally altering the length of the day on Earth.
ETH researchers published studies in *Nature Geoscience* and *Proceedings of the National Academy of Sciences (PNAS)*, detailing how climate change affects polar motion and the length of the day.
The PNAS study shows that climate change is increasing the length of the day by a few milliseconds. This impact is greater than the effect of tidal friction caused by the moon, which has influenced the length of the day for billions of years.
Melting ice masses also alter the Earth's axis of rotation. Over long timeframes, this polar motion can move the rotation axis points on the Earth's surface by about ten meters per hundred years.
The study highlights that processes on and inside the Earth are interconnected. Climate change is affecting the Earth's axis of rotation, potentially altering dynamics within the Earth's core.
Even minor changes in the Earth's rotation must be considered when navigating in space. Slight deviations on Earth can translate to significant deviations over large distances, affecting space missions such as landing probes on other planets.