US for new time standard, China, Britain say no
Updated: 2012-01-06 08:10
By Wang Xiaodong (China Daily)
BEIJING - One night, several thousand years later, you might wake up to find your digital clock showing it's 8 am in the morning.
Your clock is accurate and you're not caught in a science fiction. Clock time might not signify a particular time of the day, as we know it, if a proposal to amend the global standard of timekeeping is passed at a conference in the International Telecommunication Union (ITU) in Geneva in mid-January.
The proposal, put forward by the United States, suggests a switch to International Atomic Time (TAI) from Coordinated Universal Time (UTC), the timekeeping standard currently followed across the world.
"The proposal is backed by most developed countries, and a vote is likely at a conference of the ITU in mid-January," said Dong Shaowu, a senior researcher of the National Time Service Center under the Chinese Academy of Sciences, and a member of the Chinese delegation to the conference.
The more precise TAI might bring technical benefits to some industries, such as satellite navigation and air-traffic control systems, according to Dong.
"Even if this proposal is approved, it will not impact public life in the short term in a big way. However, some industries that require high precision of time will be affected," said Liu Changhong, a senior engineer at the National Time Service Center.
The decision to be made in Geneva may be the most important since 1961, when the world adopted UTC, based on Greenwich Mean Time - the cornerstone of international timekeeping since 1884.
Since then time has ticked in keeping with the Earth's diurnal orbit around the sun. However, the Earth is rotating at a lower speed due to various reasons such as friction from the ocean's tides, creating a gap between UTC and TAI, a more constant timekeeping standard based on around 400 atomic clocks ticking away around the globe. A later convention was adopted to synchronize the two by adding a "leap second" whenever the difference became greater than 0.9 seconds.
"Since 1972, 34 adjustments have been made to synchronize the UTC and the TAI," said Liu.
However, adding a leap second requires a huge amount of work and can be a burden to some industries such as satellite navigation and it is a major reason why some countries want to amend the time-keeping standard, according to experts.
"Some satellite experts in China also complain about the current timekeeping system," said Liu. "Dropping the leap second would give us great relief."
However, some experts hold a different opinion. "We should be cautious when making decisions to change the timekeeping standard, as it has potential influence on all people's lives and habits," said Dong.
For example, many electronic devices that are in daily use would have to be readjusted if the new standard was adopted, he added.
Although the change would not have immediate effects on people's lives, in the long term, thousands of years later for example, sticking to the TAI may gradually cause a big difference between the official time and time perceived by people due to the changing rotation speed of the Earth, Dong said.
According to Dong, China and several other countries such as Britain are against the idea. "We should be cautious and make thorough consultations before making any decision."
"Even in the technical field there is no proof to indicate that continuing to follow UTC would cause trouble to technological research and industries having a high demand for precision of time," Dong added.
"I don't think we should abolish the current timekeeping standard. The UTC does not pose a big problem to scientific research, but I am afraid getting rid of it may have unforeseen impact on our lives and habits," said Wang Tao, an engineer with China Aerospace Science and Technology Corporation.