Earth's Day Lengthens 1.33 Milliseconds per Century as Climate Change Slows Rotation at 3.6-Million-Year High
Updated
Updated · Forbes · Jun 7
Earth's Day Lengthens 1.33 Milliseconds per Century as Climate Change Slows Rotation at 3.6-Million-Year High
2 articles · Updated · Forbes · Jun 7
Summary
New research from the University of Vienna and ETH Zürich found Earth’s day is lengthening by about 1.33 milliseconds per century, the fastest climate-driven slowdown in at least 3.6 million years.
Melting glaciers and polar ice sheets are shifting mass from the poles into the oceans, slightly bulging the planet at the equator and reducing its rotation speed as sea levels rise.
The study reconstructed ancient day-length changes from benthic foraminifera fossils and machine-learning analysis, and said the 2000-2020 increase was unmatched in the record it examined.
Even tiny shifts in day length can disrupt satellite navigation, space missions and global timekeeping, all of which depend on precise measurements of Earth’s rotation.
Short-term fluctuations have still produced some of the shortest days since 2020, but researchers said climate-driven slowing could exceed the moon’s long-term effect by 2100 under high-emissions scenarios.
With Earth's rotation becoming more erratic from climate change, are our satellite navigation and global timekeeping systems at risk?
Earth's long-term slowing is now mixed with short-term speeding. What does this rotational paradox mean for predicting our planet's future?
If human impact will soon outpace the moon in slowing Earth's spin, what unforeseen planetary consequences could this shift trigger?
Climate Change Is Making Earth's Days Longer: The Science and Consequences of a 1.33 Millisecond Increase per Century
Overview
Recent scientific findings confirm that Earth's rotation is slowing down, causing our days to become slightly longer. This change is mainly driven by human activities that contribute to climate change, especially the rapid melting of polar ice sheets and glaciers. As ice melts, vast amounts of water move from the poles toward the equator, shifting Earth's mass outward from its axis. This redistribution slows the planet's spin, much like a figure skater extending their arms. The resulting changes not only affect timekeeping and technology but also highlight humanity's growing impact on Earth's fundamental systems.