A Second Here a Second There May Just Be a Waste of Time

On Jan 19, the world will go to battle over a second. In Geneva, 700 delegates from about 70 nations attending a meeting of a United Nations telecommunications agency will decide whether to abolish the leap second.

Unlike the better-known leap year, which adds a day to February in a familiar four-year cycle, the leap second is tacked on once every few years to synchronize atomic clocks — the world’s scientific timekeepers — with Earth’s rotational cycle, which, sadly, does not run quite like clockwork. The next one is scheduled for June 30 (do not bother to adjust your watch). The United States is the primary proponent for doing away with the leap second, arguing that the sporadic adjustments, if botched or overlooked, could lead to major foul-ups if electronic systems that depend on the precise time — including computer and cellphone networks, air traffic control and financial trading markets — do not agree on the time.