The General Conference on Weights and Measures (GCPM) has voted to eliminate leap seconds, the periodic adjustments that keep Coordinated Universal Time (UTC) aligned with Earth's rotation. The decision, reported by The Register, follows concerns that a future negative leap second—needed because Earth's rotation has recently sped up—could cause widespread failures.
The GCPM's resolution warns that a negative leap second has never been applied and poses a high risk of anomalies in critical infrastructure. It estimates the preparation cost for industries relying on time synchronization would be similar to Y2K remediation, which historians put at $300–600 billion. The group also cited the growing reliance on IoT devices, smart grids, and virtual services, where a leap second could cause malfunctions.
The replacement, called "Continuous UTC," will allow UT1 and UTC to diverge by up to 3,600 seconds and takes effect next year. The Register notes that this is similar to how daylight saving time works, though it points out that inconsistent mitigation methods among service providers have already caused timing discrepancies.