Key Takeaway: Global warming is slowing Earth’s rotation faster than any time in 3.6 million years, adding milliseconds to each day and threatening satellite navigation systems.
Climate change is literally making our days longer—and scientists say it’s happening at a speed not seen since the late Pliocene epoch, over 3.6 million years ago. New research published in the Journal of Geophysical Research: Solid Earth reveals that melting ice sheets and rising sea levels are redistributing planetary mass, gradually braking Earth’s spin.
How Climate Change Affects Earth’s Rotation
According to researchers at ETH Zurich and the University of Vienna, climate-related factors currently lengthen each day by approximately 1.33 milliseconds per century. While this may seem negligible, the rate is geologically unprecedented.
“This rapid increase in day length implies that the rate of modern climate change has been unprecedented at least since the late Pliocene, 3.6 million years ago,” said study co-author Benedikt Soja, a geodesist at ETH Zurich. “The current rapid rise in day length can thus be attributed primarily to human influences.”
The “Figure Skater” Effect Explained
The phenomenon works similarly to a figure skater slowing their spin by extending their arms. As polar ice melts, water mass shifts toward the equator, altering Earth’s moment of inertia and reducing rotational speed.
Study co-author Mostafa Kiani Shahvandi of the University of Vienna explained: “Never before or after that has the planetary ‘figure skater’ raised her arms and sea levels so quickly as in 2000 to 2020.”
Research Methodology: Fossils and AI
To reconstruct day-length changes across millions of years, the research team analyzed:
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Benthic foraminifera fossils – single-celled marine organisms preserving ancient ocean chemistry
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Deep learning algorithms – processing paleoclimate data with uncertainty quantification
“From the chemical composition of the foraminifera fossils, we can infer sea-level fluctuations and then mathematically derive the corresponding changes in day length,” Kiani Shahvandi noted.
Future Implications: When Climate Change Beats the Moon
The study projects alarming consequences by 2100:
| Factor | Impact on Day Length |
|---|---|
| Climate change | Expected to dominate |
| Lunar tidal friction | Currently primary cause |
| Net effect | Increased milliseconds daily |
Critical concern: Even millisecond-level changes disrupt:
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GPS and satellite navigation accuracy
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Space mission planning
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Astronomical timekeeping systems
Why This Matters
While previous ice ages altered Earth’s rotation, modern climate change operates at exceptional velocity. Only one period (~2 million years ago) approached current rates—and even that was slower than 2000-2020 measurements.
Bottom line: Human-driven global warming is literally changing how time passes on Earth, with technological consequences extending far beyond environmental damage.
Related Topics: climate change effects, Earth rotation speed, melting ice sheets, sea level rise impact, geodesy research, satellite navigation problems, anthropogenic climate change, Pliocene epoch comparison
Research Sources: ETH Zurich, University of Vienna, Journal of Geophysical Research: Solid Earth (2026), PNAS (2024)
