BIPM to Vote on Ending 27 Leap Seconds by 2035, Replacing Them With a Leap Hour
Updated
Updated · ABC News · Oct 12
BIPM to Vote on Ending 27 Leap Seconds by 2035, Replacing Them With a Leap Hour
3 articles · Updated · ABC News · Oct 12
Summary
Delegates meeting in Versailles on Oct. 12-15 will decide whether to retire leap seconds, a system added 27 times since 1972 and last used in 2016.
The push reflects growing technical risk: leap seconds arrive irregularly, can break software built on always-forward time, and could soon require the first-ever negative leap second as Earth has sped up since about 2020.
UTC now relies on atomic clocks rather than Earth's uneven rotation, which can vary by about a millisecond a day because of lunar pull, atmosphere, oceans, melting glaciers and shifts inside the planet.
Under the leading proposal, UTC would drift until it is an hour out of sync with Earth's rotation, then a future 'leap hour' would reset it; at current rates, that could take more than 1,000 years.