Scrap leap second? Decision in 2023

Countries gathered at Geneva conference cannot agree; more studies needed to assess impact

GENEVA • It is no split-second decision. In fact, countries are at such odds over whether to do away with the "leap second" - an extra second periodically added to compensate for irregularities in the Earth's rotation around the sun - that they have put off deciding the matter until 2023, the United Nations said.

Country representatives gathered for a conference in Geneva, hosted by the UN's International Telecommunication Union (ITU), have been haggling over the issue since the beginning of the month without reaching an agreement.

The World Radiocommunication Conference (WRC-15) "has decided that further studies are required on the impact and application of a future reference time-scale, including... suppressing the so-called leap second", ITU said in a statement yesterday.

The WRC conferences are held only once every four years, and a report on the impact of removing the leap second would be prepared for the conference to be held in eight years' time, the UN agency said.

The leap second has been a bone of contention among experts for years. There have been 26 occasions since 1971 when the leap second was added, most recently on June 30 this year.

Timekeepers adjust high-precision clocks so they remain in sync with the Earth's rotation, which is affected by the gravitational tug of the sun and the moon, in a bid to simplify Coordinated Universal Time (UTC), the official moniker for GMT.

The decision on when to add an extra second falls to the Earth Orientation Centre, a Paris-based division of the International Earth Rotation and Reference System Service, and must be announced "at least eight weeks in advance", ITU spokesman Sanjay Acharya said.

But such additions, which occur about once every three years, can be complicated due to computer systems' reliance on exact time measurements. Debate has intensified in recent years over making the addition of seconds to Coordinated Universal Time more predictable, following technology disruptions after the modification in 2012.

However, some countries would like to see the leap second done away with. They argue that throwing an extra second into the mix can, as in 2012, impact the Internet, which sends data around the world in tiny packets that are then stitched together in micro-seconds.


A version of this article appeared in the print edition of The Straits Times on November 20, 2015, with the headline 'Scrap leap second? Decision in 2023'. Print Edition | Subscribe