One Second Less: the Melting of the Polar Ice Caps is Slowing Down the Speed at Which the Planet Rotates

New research suggests that the melting of Antarctic ice has consequences on the speed of planetary spin and that there is a need to discuss how to adjust the “UTC” standard time.

clock, time, climate change
How should they adjust the time in the future?

In the digital age, where temporal accuracy is crucial for the functioning of the internet, telecommunications and financial markets, the climate crisis presents us with a truly unexpected challenge: polar melting is slowing down the rotation of the planet and affects Coordinated Universal Time (UTC), the global time reference.

The study by Dr. Duncan Carr Agnew, of the University of California at San Diego, published in Nature, found that the thaw in Greenland and Antarctica accelerated the reduction of the Earth's angular velocity. This means that the planet takes a little longer to rotate on its axis, altering the natural rhythm of time known as UT 1.

UT 1, also known as Universal Time 1, is a time standard based on the rotation of the Earth. Basically, it records how long it takes the Earth to complete a complete rotation in relation to distant stars

UTC, the basis of global synchronization, is based on the accuracy of atomic clocks (TAI), but is adjusted to the pace of terrestrial rotation (UT1) by inserting "interlayer seconds" when necessary. These additional seconds, added at the end of a day in June or December, allow atomic and terrestrial time to coincide.

The less thought-out impact brings new problems

However, the polar thaw is changing the rules of the game. The loss of mass at the poles and their redistribution to the equator is slowing down the Earth's rotation, which delays the need for the second intercalary.

To adjust both clocks it has been necessary, on several occasions since 1972, to add a second intercalate, that is, to make a specific minute last 61 seconds.

Agnew estimates that, due to this effect, the second negative intercalate, which was originally planned for 2026, could be delayed until 2029. Although a second seems like an insignificant change, in today's digitized world, where networks and financial systems depend on precise synchronization, an extra second or less can have important consequences.

melting ice, antarctica
The melting redistributes the mass of the planet differently

"If it is decided, it would be the first time in history that a second negative intercalar would be applied, so it will be difficult to make sure that all the interconnected computers in the world can remain synchronized," the experts explain.

A global dilemma: second positive or negative intercalate?

The scientific community is still debating whether the second negative intercalate is the best solution. Some experts fear that the interruption in global synchronization that would cause this change could lead to errors and problems in computer systems.

The study indicates that the melting in Greenland and Antarctica may have reduced, more quickly than before, the angular velocity of the Earth.

On the other hand, maintaining synchronization without adjusting UTC could generate a gradual gap between atomic and terrestrial time, with potential long-term repercussions.

Beyond time: a new climate change challenge

While the slowdown of the Earth may seem like a minor problem compared to other effects of climate change, this phenomenon reminds us of the global scope of the environmental crisis.

Polar melting not only raises the sea level, but also modifies the rotation of the planet, evidencing the profound influence that human activity has on the Earth system. While the scientific community seeks solutions to this new challenge, the increase in temperatures forces us to reconsider time management on a global scale.

Reference of the news:

Agnew, DC A global timing problem postponed due to global warming. Nature (2024).