Climate Change Is Lengthening Earth's Days, Study Finds

Rising seas from melting glaciers are slowing Earth's rotation, extending days by 1.33 milliseconds per century.

Mar. 31, 2026 at 6:49pm

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A highly structured abstract painting in soft, earthy tones of green, blue, and brown, featuring sweeping geometric arcs, concentric planetary circles, and precise botanical spirals, conceptually representing the complex scientific forces behind the slowing of Earth's rotation due to climate change.As climate change accelerates the melting of glaciers and ice sheets, the resulting rise in sea levels is causing Earth's rotation to slow, lengthening the length of our days in an unprecedented way.Greenbelt Today

A new study published in the Journal of Geophysical Research: Solid Earth has found that climate change and rising sea levels are causing Earth's rotation to slow, lengthening the length of our days. The researchers used microscopic marine fossils and a deep-learning algorithm to determine that the current rate of change in day length is unprecedented in the last 3.6 million years, and can be primarily attributed to human-caused climate change.

Why it matters

The rapid increase in day length has implications for critical infrastructure like GPS, which relies on precise data about the Earth's position and rotation. While the changes are small, just milliseconds, they can cause problems for space navigation and other applications that require accurate information about the Earth's rotation.

The details

The study found that melting glaciers and ice sheets are causing sea levels to rise, redistributing the Earth's mass away from its rotational axis. This increases the planet's moment of inertia, slowing its spin and lengthening the length of each day. The researchers analyzed fossilized marine microorganisms called foraminifera to reconstruct changes in day length over the past 3.6 million years, and developed a deep-learning algorithm to account for uncertainties in the paleoclimate data. They determined that the current rate of increase in day length, about 1.33 milliseconds per century, is unprecedented in at least the last 3.6 million years.

  • The study was published on March 10, 2026.
  • The researchers analyzed changes in day length over the past 3.6 million years.

The players

Benedikt Soja

A professor of space geodesy at ETH Zurich and a co-author of the study.

Mostafa Kiani Shahvandi

The lead author of the study and a geophysicist at the University of Vienna.

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What they’re saying

“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. The current rapid rise in day length can thus be attributed primarily to human influences.”

— Benedikt Soja, Professor of space geodesy at ETH Zurich

“Only one time — around 2 million years ago — the rate of change in length of day was nearly comparable, but never before or after that has the planetary 'figure skater' raised her arms and sea-levels so quickly as in 2000 to 2020.”

— Mostafa Kiani Shahvandi, Geophysicist at the University of Vienna

What’s next

Researchers will continue to monitor changes in Earth's rotation and day length to better understand the long-term impacts of climate change on our planet's dynamics. This data will be crucial for maintaining the accuracy of critical infrastructure like GPS that relies on precise information about the Earth's position and rotation.

The takeaway

This study provides clear evidence that human-caused climate change is having a measurable impact on the fundamental physical properties of our planet, with the potential to disrupt important technological systems. It underscores the need for urgent action to address the root causes of climate change and mitigate its far-reaching consequences.