Earth is spinning faster and recently recorded its shortest day ever, scientists say. June 29, 2022 was 1.59 milliseconds shorter than the average day, scientist Leonid Zotov told CBS News.
The normal length of a day is 24 hours or 86,400 seconds. But in recent years, the Earth’s rotation has accelerated, shortening some days by milliseconds. “Since 2016 the Earth has started to accelerate,” said Zotov, who works at Lomonosov State University in Moscow and recently published a study about what might cause the changes in the Earth’s rotation. “This year it’s rotating faster than 2021 and 2020.”
Zotov and his colleagues believe the variation could be caused by Earth’s tides.
He says not every day is getting shorter, but if the trend continues, atomic time – the universal way of measuring time on Earth – may have to change. Some scientists suggest introducing a negative leap second. “Since we cannot change the hands of the clock associated with the rotation of the Earth, we adjust the scale of the atomic clock,” he said.
Unlike leap years, in which an extra day is added, a negative leap second would mean clocks skip a second.
Some engineers oppose the introduction of a leap second, as it could lead to large-scale and catastrophic technological issues. Meta engineers Oleg Obleukhov and Ahmad Byagowi, who is also a researcher, wrote a blog post for Meta that supports an industry-wide effort to stop the future introduction of leap seconds.
“Negative jump second handling has been supported for a long time, and companies like Meta often run simulations of this event,” they told CBS News. “However, it has never been verified on a large scale and will likely lead to unpredictable and catastrophic outages around the world.”
The idea, which was introduced in 1972, “primarily benefits scientists and astronomers by allowing them to observe celestial bodies using UTC [Coordinated Universal Time] for most purposes,” they wrote in the suspension.
“The introduction of new leap seconds is a dangerous practice that does more harm than good, and we believe it is time to introduce new technologies to replace it,” they write.
While positive leap seconds could cause a time jump, causing IT programs to crash or even corrupt data, a negative leap second would be worse, they argue.
“The impact of a negative leap second has never been tested on a large scale; it could have a devastating effect on software that relies on timers or schedulers,” they write. “Either way, every leap second is a significant source of pain for people managing hardware infrastructure.”
The pair believe that one of the many factors contributing to the Earth’s faster rotation could be the constant melting and refreezing of ice on the world’s highest mountains.
“It’s all about the law of conservation of momentum that applies to our planet Earth. Every person on the planet contributes to the momentum of the earth’s angular velocity based on the distance from the earth’s axis of rotation,” Obleukhov and Byagowi told CBS . News. “So when things move around, the earth’s angular velocity can vary.”
“This phenomenon can be simply visualized by thinking of a rotating figure skater, who manages angular velocity by controlling his arms and hands,” they said. “As they extend their arms, the angular velocity decreases, conserving the skater’s momentum. Once the skater gets their arms back, the angular velocity increases. The same is happening here right now because of the warming of the Earth. The ice melt and lead to an increase in angular velocity’.
Zotov and his colleagues Christian Bizouard and Nikolay Sidorenkov will present their research in this month’s Asia Oceania Geosciences Society conference on geosciences, according to timeanddate.comwhich first reported the Earth’s faster rotation and shorter days.