The standard length of a day is 24 hours or 86,400 seconds. However, scientists reported the shortest day on June 29, 2022, which was 1.59 milliseconds less than the average. Lomonosov Moscow State University employee, Leonid Zotov, released a study explaining why the Earth is spinning faster. He wrote, “This year it rotates quicker than in 2021 and 2020.”
Zotov and his colleagues believe the rotation is speeding up due to the Earth’s tides. He confirms that not every day is not shorter, but if the trend continues, the way time is measured on Earth will have to change. Zotov said, “Since we can not change the clock arrows attached to the Earth rotation, we adjust the atomic clock scale.” Like a leap year, a negative leap second means clocks skip one second.
Meta engineers Oleg Obleukhov and Ahmad Byagowi oppose introducing a leap second. They wrote a blog post for Meta explaining why this can lead to a large-scale tech issue. The duo told CBS News, “Negative leap second handling is supported for a long time and companies like Meta often run simulations of this event. However, it has never been verified on a large scale and will likely lead to unpredictable and devastating outages across the world.”
The pair continued, “It is all about the law of conservation of momentum that applies to our planet Earth. Every atom on the planet contributes to the momentum of the Earth’s angular velocity based on the distance to the rotation axis of the Earth. So, once things move around, the angular velocity of the Earth can vary.”
The concept of a leap second was initially proposed in 1972. Obleukhov and Byagowi wrote that the update “mainly benefits scientists and astronomers as it allows them to observe celestial bodies using UTC [Coordinated Universal Time] for most purposes. Introducing new leap seconds is a risky practice that does more harm than good, and we believe it is time to introduce new technologies to replace it. The impact of a negative leap second has never been tested on a large scale; it could have a devastating effect on the software relying on timers or schedulers. In any case, every leap second is a major source of pain for people who manage hardware infrastructures.”
Obleukhov and Byagowi believe one of the main factors causing the Earth’s rotation to accelerate is the constant melting and refreezing of the tallest mountains. They said, “This phenomenon can be simply visualized by thinking about a spinning figure skater, who manages angular velocity by controlling their arms and hands. As they spread their arms the angular velocity decreases, preserving the skater’s momentum. The angular velocity increases as soon as the skater tucks their arms back in. Same happens here at this moment because of rising temperatures on Earth. Ice caps melt and lead to angular velocity increase.”