闰秒自1972年引入以来已调整过27次，旨在调和依据地球自转的天文时间与极度精确的协调世界时（UTC）。然而，此种校正方式长期困扰电信、电网及数据伺服器等基础设施的营运者，各机构采用不同的平摊技术来因应，促使全球计时机构原已决议在2035年前彻底废除闰秒。

近年来地球自转因地核变化而反常加速，导致2035年前可能需首次扣除一秒，即实施前所未见的「负闰秒」。由于多数电脑系统预设闰秒均为正值，删除一秒可能对导航、通信与电网等数位时间戳系统造成难以预测的严重故障，这项潜在危机进一步促使计时机构考虑提前终结闰秒机制。

为了彻底消除基础设施面临的风险，国际计时机构正讨论以「闰时」取代闰秒，一旦通过可能需累积上千年才需调整一次，实质上将时间校准需求降至最低。尽管这有助于科技巨头与官方维护数位系统稳定，但也标志著人类时间计量将正式切断与天体自转之间长达数千年的古老文化连结。

The leap second, introduced in 1972 and applied 27 times, was designed to reconcile astronomical time based on Earth's rotation with ultra-precise Coordinated Universal Time (UTC). However, these adjustments have long troubled operators of critical infrastructure such as telecoms, power grids, and data servers, prompting international timekeeping authorities to vote to abolish the mechanism by 2035.

The situation has grown urgent because Earth's rotation has accelerated since around 2015 due to core dynamics, introducing a significant risk that an unprecedented negative leap second might be needed before 2035. Because countless digital systems are programmed assuming only positive leap seconds, deleting a second could trigger catastrophic failures across global telecommunications, navigation, and power networks.

To permanently eliminate these technological vulnerabilities, global timekeepers are preparing to vote on replacing leap seconds with a leap hour, which would only accumulate over millennia and effectively render regular corrections obsolete. While this reform secures modern digital infrastructure, it represents a profound cultural shift that severs human timekeeping from its ancient celestial and astronomical foundations.