World Timekeepers Set to Vote on Eliminating Leap Seconds in Favor of Leap Hour
Delegates at the BIPM meeting in Versailles will decide whether to drop leap seconds and replace them with a future “leap hour”.
Since 1972, 27 leap seconds have been added to Coordinated Universal Time to compensate for variations in Earth’s spin. This week, delegates meeting near the Versailles palace will vote on abandoning the leap-second system, opting instead for a “leap hour” correction only when UTC is an hour out of sync with solar time—a scenario that may not arise for over a millennium. Scientists explain that Earth’s rotation fluctuates due to factors such as atmospheric winds, ocean currents, and glacial melt, making the traditional second insufficient for high-precision technologies like GPS.
The irregular insertion of leap seconds has already caused outages at sites such as Cloudflare and Reddit, and a potential negative leap second raises further software concerns. Proponents argue the change simplifies global timekeeping, while some warn it severs the link between clocks and the planet’s actual rotation. Should the vote pass, institutions like Australia’s National Measurement Institute will no longer need to staff New Year’s Day for leap-second checks.
