You will have to wait for a second longer than usual to get into 2017 as timekeepers will add a “leap second” to the final minute of 2016.
On December 31st, 2016, a “leap second” will be added to the world’s clocks at 23 hours, 59 minutes and 59 seconds Coordinated Universal Time (UTC), the US Naval Observatory said in a statement.
UTC is computed in Paris, France, at the International Bureau of Weights and Measures. Historically, time was based on the mean rotation of the Earth relative to celestial bodies and the second was defined in this reference frame.
Measurements show that the Earth, on average, runs slow compared to atomic time, at about 1.5 to 2 milliseconds per day. Scientists have determined that after roughly 500 to 750 days, the difference between Earth rotation time and atomic time would be about one second.
The International Earth Rotation and Reference Systems Services (IERS) is the organisation which monitors the difference in two time scales and calls for leap seconds to be inserted in or removed from UTC when necessary to keep them within 0.9 seconds of each other. When the system was instituted in 1972, the difference between International Atomic Time and UTC was determined to be 10 seconds.
As leap seconds can pose a threat to computer systems, the IERS – the group responsible for administering international time – typically give a six months’ notice about the time changes, and only places them at the end of December or June.
However, according to he UK based New Scientist Journal, there have been calls to stop adding leap seconds and to let the earth’s rotation gradually diverge from the time.
Instead of adding leap second every few years, we can make the modifications in the long run. So in every 100 years, an additional three minutes can be added. But this proposal is still under debate by the international community of scientists.