From ClimateRealism

By Anthony Watts

Euronews, writing in a recent article titled “Unprecedented in the past 3.6 million years’: How human-made climate change is making days longer,’” claims that climate change is slowly but measurably altering Earth’s rotation, lengthening the day by about 1.33 milliseconds over a century, implying troubling consequences ahead for society and the planet because it is “unprecedented in the past 3.6 million years.” This is patently and demonstrably false. Variations in Earth’s length of day (LOD) of this magnitude or greater are routine and naturally occurring. The 1.33 millisecond variation poses no biological or societal threat, and technologies tied to time can be adjusted, if necessary, to account for the change.

Euronews’ article relies on a recent study suggesting that melting ice and mass redistribution are influencing Earth’s rotation. While redistribution of mass can affect angular momentum of the spinning Earth, which is basic physics, the framing of the article implies something unprecedented or destabilizing. The historical record shows otherwise.

Earth’s rotation has never been perfectly constant. It fluctuates continuously due to multiple natural mechanisms operating on different timescales.

Seasonal redistribution of mass in the atmosphere and oceans adds about 0.5–1 millisecond annually, as wind systems shift and ocean currents adjust. Interannual climate patterns such as El Niño–Southern Oscillation (ENSO) contribute an additional ±0.3–0.5 millisecond variation. None of these processes are new, and none are evidence of planetary instability.

In that context, a 1.33-millisecond shift sits squarely within the range of normal background variability, and is nothing to be concerned about.

The long-term trend — Earth gradually slowing due to tidal friction from the Moon — is also well understood. Based on 2,500 years of historical astronomical eclipse observations, science estimates the average increase in LOD at approximately +1.7 to +1.8 milliseconds per century. That gradual braking has been operating for hundreds of millions of years. It is not caused by industrial emissions, nor is it accelerating catastrophically.

Even more inconvenient for alarmist framing is the fact that Earth has recently sped up.

From the mid-2010s through the early 2020s, Earth’s rotation accelerated rather than slowed. June 29, 2022 was the shortest day ever recorded in the atomic timekeeping era — approximately 1.59 milliseconds shorter. That record underscores how dynamic Earth’s rotation is and how multiple forces, including core-mantle interactions and atmospheric changes, compete to influence it.

If climate change were driving a simple, monotonic slowing of the planet’s spin, we would not expect to see record-setting shorter days in recent years.

The biological implications of a 1.33-millisecond change are effectively nonexistent. Humans, animals, and plants rely on circadian rhythms tuned to approximately 24 hours — not to thousandths of a second. A millisecond represents 0.001 seconds. In percentage terms, 1.33 milliseconds is roughly 0.000015 percent of a day. There is no plausible physiological pathway by which such a miniscule adjustment could disrupt ecosystems or human health. No living entity can detect or be affected by a thousandth of a second change in the length of a day.

Technologically, the situation is equally unremarkable. Modern systems already account for irregularities in Earth’s rotation. Since 1972, 27 leap seconds have been added to Coordinated Universal Time (UTC) to keep atomic clocks synchronized with Earth’s variable spin. Because of recent rotational acceleration, scientists are even discussing the possibility of implementing a negative leap second — subtracting one second for the first time.

According to Earth orientation data maintained by the International Earth Rotation and Reference Systems Service (IERS), decadal fluctuations driven primarily by angular momentum exchange between the solid Earth and its fluid outer core routinely produce variations of  about 3–4 milliseconds. These are the largest short-term departures from the long-term trend and have been occurring for as long as we have had precise measurements.

Satellite navigation systems, astronomical observatories, telecommunications networks, and financial trading platforms all rely on precise timekeeping. They already ingest continuous Earth orientation parameter updates from IERS and adjust accordingly. The IERS monitors the rotation of the Earth, which is irregular, providing data on (the difference between Terrestrial Time and Universal Time) and potential leap seconds. These systems routinely handle corrections far larger than 1 millisecond without disruption.

Consider also that society adjusts clocks by one hour every year in regions that observe daylight saving time; a shift 3.6 million times larger than the change Euronews highlights. Leap years add an entire day. Leap seconds add or subtract a full second. By comparison, a millisecond-scale variation is trivial.

The total peak-to-peak variation in Earth’s LOD over the past century — combining effects such as tidal braking, core-mantle coupling, seasonal atmospheric effects, ENSO variability, and we find LOD acceleration has been on the order of 5–8 milliseconds. These variations occurred long before modern concerns about climate change and reflect the complex physics of a rotating, fluid planet with a molten core, dynamic oceans, shifting winds, and gravitational interactions with the Moon.

Earth is not a rigid clock. It is a complex and variable geophysical system. Presenting a 1.33-millisecond change as evidence of climate destabilization creates a false narrative of crisis. Yes, mass redistribution, whether from ice melt, atmospheric changes, or ocean circulation can influence rotational dynamics. But that influence is small, embedded within larger natural variability, and well within the bounds that scientists and engineers have been tracking and adjusting for decades.

The practical consequence of LOD variability is careful timekeeping, something modern civilization already excels at managing. A millisecond does not threaten human biology. It does not endanger plant life. It does not destabilize ecosystems, and it does not overwhelm modern technology.

If Euronews had bothered to even do a modicum of research into this phenomenon, they’d know their story is based on misrepresentation of the cause of a change that can’t be sensed and promotes false alarm. Instead, they went the “click bait” route, choosing narrative over truth; badly misleading their readers in the process.