Climate crisis could change how time is measured: Study

A study suggests that the climate crisis may alter how time is measured. Environmental changes, such as shifts in Earth's rotation and variations in day length, could prompt adjustments to timekeeping systems. This highlights the profound impact of climate change on fundamental aspects of our understanding and measurement of time.

In a historic first, timekeepers may have to subtract a second from world clocks by 2029

From increasing health risks to polar ice melting, the effects of global warming are well-known. Now, a new study sheds light on an unusual consequence. Researchers have found that global warming could lead to delaying the need for history's first "negative leap second”.

Negative leap second refers to a minute with only 59 seconds, which could cause chaos on computer systems across the world. This will be a massive shift since to date time has been added, never subtracted. For most of history, time was measured by the rotation of the Earth. This changed in 1967, when atomic clocks -- which use the frequency of atoms as their tick-tock – were embraced, leading to a more accurate era of timekeeping.

To address this, whenever the difference between the two measurements approached 0.9 of a second, a "leap second" was added to Coordinated Universal Time (UTC), the internationally agreed standard. Hence, since 1972, 27 leap seconds have been added to UTC. The last one was in 2016.

Now, Earth’s rotation has gained speed and is overtaking atomic time so the two measurements are in sync. So, for the first time, timekeepers may have to introduce the first-ever negative leap second, the new study revealed.

"This has never happened before, and poses a major challenge to making sure that all parts of the global timing infrastructure show the same time," study author Duncan Agnew told AFP.

"Many computer programs for leap seconds assume they are all positive, so these would have to be rewritten,” he added.

Agnew further explained that it is because of climate change that a negative leap second might have to be added to UTC as soon as 2026. However, since 1990, melting ice in Greenland and Antarctica has slowed down the Earth's rotation, the study explained. This has delayed the need for a negative leap second until at least 2029. "When the ice melts, the water spreads out over the whole ocean; this increases the moment of inertia, which slows the Earth down," Agnew told AFP. 

So, for now, the need for the “unprecedented” negative time leap has been delayed by three years.

Sourced from Mint‍