Human-caused climate change is impacting Earth in surprising ways. Recent research reveals that our planet’s rotation is slowing at a pace we haven’t seen in 3.6 million years. Specifically, sea level rise is making days longer by about 1.33 milliseconds per century. This change is all tied to how mass on Earth is distributed, much like a figure skater who spins faster when they pull in their arms.
According to experts, the moon’s gravitational pull is a significant factor in the long-term changes in Earth’s spin. It adds about 2.4 milliseconds to our days every century. However, this is countered by an effect called glacial isostatic adjustment, where the planet’s crust rises after glaciers melt, shortening days by around 0.8 milliseconds per century. Together, these factors result in a small overall lengthening of days.
Climate change plays an increasingly large role in altering the planet’s rotation speeds. Mostafa Kiani Shahvandi, a geoscientist at ETH Zurich, highlights that today’s rapid increase is unusual when compared to historical data. He and fellow researcher Benedikt Soja examined ancient fossils to look back at Earth’s history. Their work revealed that today’s rate of change is one of the most significant in the last 3.6 billion years.
Interestingly, a similar increase occurred about 2 million years ago during the Early Pleistocene, a time characterized by rising carbon dioxide levels. It’s a reminder of how natural cycles can mirror our current situation, though today’s changes are largely driven by human activity.
Future projections are concerning. If greenhouse gas levels rise, we could see a lengthening of 2.62 milliseconds per century by 2080. While these changes may seem minor on a daily basis, they could impact technologies that rely on precise measurements, like spacecraft instruments or computing systems.
These findings stress the urgency of addressing climate change. Shahvandi points out that the data reflects a rapid shift in our environment, such as the melting of polar ice and rising sea levels. Understanding these changes not only informs scientific research but also impacts daily life and future planning.
For more in-depth insights into climate-related changes, you can refer to the study published in the Journal of Geophysical Research: Solid Earth.
