Climate change is lengthening the days on Earth, according to recent analysis. The mass melting of polar ice is reshaping our planet in ways that have far-reaching consequences, affecting everything from internet traffic to GPS navigation.
The melting ice masses in Greenland and Antarctica are releasing water into the world’s oceans. This influx of water, particularly into the equatorial region, is shifting the planet’s mass. Benedikt Soja, Professor of Space Geodesy at ETH Zurich, explains that this shift impacts Earth’s rotation.
CONSERVATION OF ANGULAR MOMENTUM
Soja compares this to a figure skater who spins slower when extending their arms. The shift in mass from the poles to the equator increases Earth’s physical inertia, slowing its rotation. This is due to the law of conservation of angular momentum, which governs Earth’s rotational speed. As a result, days are getting longer, albeit by just milliseconds.
SCIENTIFIC STUDIES AND FINDINGS
Supported by NASA, researchers from ETH Zurich published studies in Nature Geoscience and Proceedings of the National Academy of Sciences (PNAS). These studies explore the effects of climate change on polar motion and the length of the day.
The PNAS study reveals that climate change, by redistributing water from poles to lower latitudes, is slowing Earth’s rotation more significantly than the tidal friction caused by the moon. This indicates that human-induced climate change may surpass natural processes that have been in effect for billions of years.
SHIFTS IN EARTH’S AXIS
Polar Motion
The melting ice not only alters Earth’s rotational speed but also shifts its axis. Over long periods, these shifts can amount to ten meters per century. Movements within Earth’s mantle and heat flows in its liquid outer core also contribute to these changes.
Comprehensive Modelling
In a study published in Nature Geoscience, Soja’s team presented the most comprehensive model to date, explaining the causes of long-period polar motion. Doctoral student Mostafa Kiani Shahvandi, lead author of the study, highlighted that processes within Earth are interconnected and influenced by climate change.
ROLE OF ARTIFICIAL INTELLIGENCE
The researchers used physics-informed neural networks, a novel AI method, to develop powerful algorithms for their study. These algorithms allowed them to model interactions between the Earth’s surface, mantle, and core accurately.
Collaborative Efforts
Siddhartha Mishra, Professor of Mathematics at ETH Zurich and recipient of the Rössler Prize, collaborated on this project. The resulting models show excellent agreement with historical data, enabling accurate future forecasts.
IMPLICATIONS FOR SPACE TRAVEL
Navigation Precision
Even slight changes in Earth’s rotation must be considered in space navigation. Precise calculations are crucial for missions like landing probes on other planets. Minor deviations on Earth can lead to significant errors over vast distances.
The research underscores the profound impact of human activities on Earth’s natural processes. As Soja concludes, humanity has a significant responsibility for the planet’s future. While the immediate effects of these changes are minor, they highlight the interconnectedness of our actions and the environment.
