World Timekeepers Propose Replacing Leap Seconds with Leap Hours
Authorities plan to abolish leap seconds as early as October and consider a leap-hour adjustment to keep atomic time aligned with Earth’s rotation.
Since 1972, Coordinated Universal Time has been kept in sync with Earth’s rotation by adding a leap second, a practice scheduled to conclude by 2035. Officials now consider terminating leap seconds as soon as October to prevent the unprecedented scenario of a negative leap second, which could jeopardize essential services such as power grids and financial markets. To replace the risky adjustment, the General Conference on Weights and Measures will vote on a resolution to introduce a leap hour, applied only when the discrepancy reaches 3,600 seconds.
This larger step would occur far less frequently, potentially only after centuries, and mirrors the familiar practice of daylight-saving time changes. Experts note that while a leap hour may still pose technical challenges, it would be more manageable for future systems. The decision will be made at the CGPM’s 28th meeting outside Paris on 13-15 October.
Why it matters
Changing how global time is adjusted could prevent disruptions to critical digital and infrastructure systems.
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