[Earth rotation, Credit to Pixabay]

Recent research has revealed that the Earth is spinning at a faster rate this summer, resulting in shorter days, which has drawn the attention of scientists and timekeepers. 

According to data from the International Earth Rotation and Reference System Service and the US Naval Observatory, July 10 lasted 1.36 milliseconds less than 24 hours, making it the shortest day recorded  this year.

The length of the day is calculated based on the time it takes for the planet to complete a full rotation, which is typically 24 hours or 86,400 seconds on average. 

In reality, various factors contribute to the irregularity of the  Earth’s rotation, including the movement of its liquid core, the gravitational pull of the moon, and seasonal variations. 

The Earth’s full rotation could take slightly more or less than 85,400 seconds, but the minor deviations of just a few milliseconds doesn’t generally have a drastic effect on our lives. 

Nevertheless, as these discrepancies accumulate over time, they can impact computers, satellites, and telecommunications, hence the tracking of  even the slightest time differences. 

That precise time is tracked by atomic clocks, which were introduced in 1955, and they count the oscillations of atoms to calculate 24 hours with high accuracy. 

These atomic clocks are fundamental in setting the  UTC, or Coordinated Universal Time, which is the global standard for timekeeping, and also in our phones and computers. 

Astronomers also rely on satellites to determine the Earth’s position relative to the fixed stars, allowing them to compare  the actual time that the Earth takes for a full rotation with the atomic clock’s time. 

Duncan Agnew, a professor of geophysics at the Scripps Institution of Oceanography, explains that the moon’s position and tides affect Earth’s rotation. 

Earth spins faster when the moon is located at higher or lower altitudes away from the equator, and slower when it is positioned directly over the equator.

Additionally, in summer, the atmosphere slows down due to the shifts, such as the jet stream’s movement.

The Earth’s rotation speed increases to compensate for the atmosphere slowing as angular momentum must stay constant.

Another contributing factor is that the Earth’s liquid core has been slowing down, causing the solid Earth to spin faster over the past 50 years. 

He states that this complex interplay of natural forces leads the Earth to spin temporarily more quickly, which causes slightly shorter days. 

Although a single abbreviated day has little impact on everyday life, when the Earth tends to spin faster, it increases the chance of needing a negative leap second, which is subtracting a second from global time, and it has never happened before. 

This prospect is concerning, as even positive leap seconds, which have been executed several times before, still cause problems in some systems.

It is predicted that a negative leap second could lead to even more confusion and errors. 

Given that  many technologies and industries rely on precise timing, including financial systems, GPS, and power grids, a negative leap second could cause major disruptions.

Surprisingly, scientists have found that climate change is slowing down Earth’s rotation, which has contributed to delaying the need for a negative leap second. 

According to Agnew,  melting ice from Antarctica and Greenland spreads the mass into the oceans, causing Earth to rotate more slowly. 

However, if global warming continues, the mass shift can also alter the Earth’s rotation axis, which has been consistent for billions of years. 

Scientists emphasize that the faster spin of Earth is still variable, and the long-term predictions are uncertain, so there is a possibility that the situation will change again in the future.