If one looks at the underlying physics it shouldn't be astounding to learn that days are getting longer as a result of climate change. In effect, warmer
temperatures lead to a slowing of Earth’s rotation at a rate we have not been seen for at least 3.6 million years.
This finding is based on new research, i.e.
Showing that rising sea levels caused by melting ice sheets are redistributing mass across the planet, reducing how fast Earth spins and gradually lengthening the day. Amazing? Not really. Earlier research has already found that the Earth's rotation axis has been displaced by melting glaciers and ground water overuse. Also, that new estimates of the inertial tensor have shown the rotation of the non-rigid Earth can be affected. (See added links at end of this post).
Of course, the deviations are extremely small, but they add up over time, especially geological eons. Researchers have found that days are currently increasing by about 1.33 milliseconds per century due to climate-related factors, a pace that stands out sharply in the planet’s recent geological history. Earlier studies by the same team established that climate change affects sea levels and, as a result, Earth’s rotation—but the new work places the trend in a geological context.
According to lead paper author (and geodisist*) Benedikt Soja of ETH Zurich, Switzerland:
“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."
Adding:
“By the end of the 21st century, climate change is expected to affect day length even more strongly than the Moon. Even though the changes are only milliseconds, they can cause problems in many areas, for example in precise space navigation, which requires accurate information on Earth’s rotation.”
Paper co-author Mostafa Kiani Shahvandi of the University of Vienna added that the effect is similar to a figure skater spinning more slowly after extending her arms. She will be slowed dramatically in terms of reduction in angular velocity, w. so that her angular speed w (f) < w (i).
This is something every college freshman doing general physics learns. What remains uncertain, according to Shahvandi, was whether climate had ever lengthened the day this quickly before. To answer that question, the research team reconstructed changes in Earth’s day length going back millions of years.
Obviously, no actual time machines are being used here, so the team relied on fossilized remains of benthic
foraminifera, single-celled marine organisms that preserve chemical signals of
past ocean conditions. By analyzing these fossils, the geodesy team was able to
infer historical sea-level fluctuations and calculate how those shifts would
have affected Earth’s rotation.
The researchers then applied a type of machine deep learning algorithm to the findings, much like I saw solar dynamics researchers do in the SDO 2025 workshop last year,
Looking Back On Last Week's Solar Dynamics Workshop - One Of The Best Meetings I've Ever Attended
designed to reflect sea-level change while accounting for the
uncertainty that comes with ancient climate data. According to
“From the chemical composition of the foraminifera fossils, we
can infer sea-level fluctuations and then mathematically derive the
corresponding changes in day length. This model
captures the physics of sea-level change, while remaining robust to the large
uncertainties inherent in paleoclimate data.”
The results show that Earth’s day length has varied
significantly over the past 2.6 million years, particularly during the
Quaternary period, when large continental ice sheets repeatedly grew and
melted. These ice-driven sea-level changes caused Earth’s rotation to speed up
or slow down at different times.
However, compared with modern measurements, the researchers
found th at today’s increase in day length is exceptional. Only one period,
around two million years ago, showed a rate of change that came close to
present-day levels, and even that episode was slightly slower than what has
been observed between 2000 and 2020. In the words of
“Never before or after that has the planetary ‘figure skater’
raised her arms and sea levels so quickly as in 2000 to 2020.”
These recent findings suggest that the current trend reflects a broader pattern of unusually rapid climate change. Looking ahead, the researchers say climate change could have an even greater influence on Earth’s rotation. By the end of the 21st century, they estimate that climate-driven effects on day length may surpass the slowing impact caused by the Moon’s gravitational pull.
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* geodisist: A specialist involved in the science of Geodesy
And:
by Anabel Scales and Chuck Collins
The February rollback of the “endangerment finding”—which provides the legal basis for regulating climate change—was many years in the works. It’s the ultimate payback for a politically engaged fossil fuel industry and the climate criminals who use their wealth, power, and position to block efforts to help us transition to a post-oil, gas, and coal era.
Who’s responsible for rolling back the endangerment finding? We believe it is time to name names so future generations—and future climate justice tribunals—will know who is responsible for incinerating our futures. Researchers at the Climate Accountability Research Project have tracked several of the key individuals working to undermine climate protection for the last two years.
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