A recent study published in Nature suggests that global warming-induced polar ice melt is causing the Earth to spin slower, potentially necessitating adjustments to our clocks. Geophysicist Duncan Agnew, the study’s author, warns that the change in Earth’s angular velocity may prompt the need for a “negative leap second” by 2029.
The melting polar ice redistributes mass, shifting the Earth’s center of mass and affecting its rotation speed. As ice melts at the poles, the mass around the equator increases, leading to a measurable slowdown in the planet’s rotation. Thomas Herring, a geophysics professor at MIT, explains that the melted water flows towards the equator, altering the planet’s distribution of mass and consequently its rotational dynamics.
Agnew underscores the unprecedented nature of the phenomenon, highlighting its impact on the Earth’s rotation, a process that typically occurs over millions of years. While Earth’s rotation has naturally slowed over geological timescales, the accelerated pace attributed to contemporary climate change is cause for concern.
The potential need to adjust clocks and timekeeping systems underscores the far-reaching consequences of climate change, extending beyond environmental and societal impacts to affect fundamental measures of time. As scientists continue to monitor Earth’s rotational changes, the study serves as a reminder of the intricate interplay between human activities and planetary dynamics.
