Global Timekeeping Shifts as Leap Seconds Are Abolished

The International Telecommunication Union (ITU) has voted to abolish the use of leap seconds, a practice that has been a source of debate in the timekeeping community for years. The decision, made at the 2022 World Radiocommunication Conference, will take effect in 2035.

The leap second was introduced in 1972 to account for the gradual slowing of the Earth's rotation. It was added to Coordinated Universal Time (UTC) to keep it in sync with astronomical time. However, the irregularity of leap seconds has caused issues for modern navigation and communication systems, which rely on precise and continuous timekeeping.

The ITU's decision to end leap seconds comes after years of debate. Proponents of the change argue that the leap second's unpredictability can disrupt critical infrastructure, including GPS systems and financial markets. Opponents, however, have expressed concerns about the potential impact on astronomical observations and the alignment of UTC with solar time.

To address these concerns, the ITU has proposed a new system that will use a more stable and predictable time scale. This new system, known as UTC without leap seconds, will be based on International Atomic Time (TAI) and will not be adjusted for the Earth's rotation. Instead, it will allow for a gradual divergence between UTC and astronomical time, which will be monitored and managed by the International Earth Rotation and Reference Systems Service (IERS).

The transition to the new timekeeping system will take place over the next 13 years, with the final leap second to be added in 2035. During this period, the ITU will work with international stakeholders to ensure a smooth transition and minimize disruptions to existing systems.

Countries and organizations will have the option to adopt the new timekeeping system earlier if they choose to do so. The ITU has stated that it will provide guidance and support to those that make the transition before 2035.