Airlines, trading floors and technology companies are braced¹ for chaos² today as world timekeepers prepare to add a leap second to global clocks.

世界钟表今天要给全球的钟表加一“闰秒”，因此航班、交易所、科技公司正在为即将到来的混乱备战。

Immediately before midnight, dials will read 11:59:60 as clocks hold their breath for a second to allow the Earth's rotation³ to catch up with atomic time.

为了使地球自转和原子时间吻合，午夜的前一刻，时钟将会凝滞一秒，表盘将会因此显示出11:59:60。

When the last leap second was added in 2012, Mozilla, Reddit, Foursquare, Yelp⁴, LinkedIn, and StumbleUpon all reported crashes and there were problems with the Linux operating system and programs written in Java. In Australia, more than 400 flights were grounded as the Qantas check-in system crashed.

上一次添加闰秒是在2012年，当时Mozilla, Reddit, Foursquare, Yelp, LinkedIn和StumbleUpon都有故障报告，Linux操作系统和Java编程也出现了问题。澳洲航空的安检系统崩溃导致澳大利亚超过400架航班取消。

Experts at Britain's National Physical Laboratory (NPL) who will officially add the second to UK time, warned that markets which are already jittery⁵ from Greece could suffer transaction delays if their software was not prepared.

英国国家物理实验室（NPL）的专家将正式把闰秒加进英国时间，他们警告称，如果系统没有做好充分准备，被希腊危机搅得不堪一击的股市将会遭受交易延迟。

"There are consequences of tinkering with time," said Peter Whibberley, Senior Research Scientist in the Time and Frequency group at NPL, who is known to colleagues as "The Time Lord."

英国国家物理实验室时间和频率组的资深科研家彼得·韦博利（Peter Whibberley）被同事们称为“时间之神”，他说：“如果不妥善处理时间的话，后果将不堪设想。”

"Because leap seconds are only introduced sporadically⁶, it is difficult to implement⁷ them in computers and mistakes can cause systems to fail temporarily.

添加闰秒的情况很少见，所以很难把它补在电脑里，稍有差错，系统就会暂时性瘫痪。

"Getting leap seconds wrong can cause loss of synchronization⁸ in communication networks, financial systems and many other applications which rely on precise timing⁹. Whenever a leap second occurs, some computer systems encounter problems due to glitches¹⁰ in the code written to handle them. The consequences are particularly severe in the Asia-Pacific region, where leap seconds occur during normal working hours."

闰秒处理不当会导致通信网络、金融体系和其他依赖精确时间计量的应用出现不同步的状况。闰秒的出现会在修复问题的编码里引发细微的差错，所以部分电脑系统就会出现问题。而其后果在亚太地区更为严重，因为该地区是在正常工作时间出现闰秒的。

European markets including London are largely closed when the event is scheduled to occur, but the change will hit trading floors in the US, Japan, Australia, South Korea and Singapore.

包括伦敦在内的大部分欧洲市场确定闰秒将要出现后都关停了。但是这样的变化会影响美国、日本、澳大利亚、韩国和新加坡的交易所。

To make matters more complicated, stock exchanges are approaching the leap second differently, with Asian markets planning to trade as normal, while US exchanges are expected to stop activity early.

股票交易市场处理闰秒的不同策略更是忙中添乱，因为亚洲市场打算正常交易，而美国市场则计划提前停止交易活动。

Dr Leon Lobo, Strategic Business Development Manager at NPL added:"Anyone who conducts transactions with those markets when the change occurs could have a synchronization issue if they are not ready."

英国国家物理实验室的战略业务发展经理莱昂·罗博（Leon Lobo）博士说：“如果市场没有准备好，那么在变化发生时和那些市场进行交易的人可能会遇到时间同步的问题。”

Many computing¹¹ systems use the Network Time Protocol¹², or NTP, to keep themselves in sync with the world’s atomic clocks. But most are not programmed to deal with an unexpected extra second.

很多计算系统用的都是网络时间协议（NTP），以保证他们和世界原子时钟是同步的。但是大多数系统的编程无法处理这多出来的“不速之秒”。

Google has even developed a special technique to deal with what it refers to as a "leap smear¹³" and has been gradually adding milliseconds to its system clocks prior¹⁴ to the official arrival of the leap second. BT's speaking clock will add a second's pause before its third pip.

谷歌甚至开发了一种特殊技术来处理所谓的“闰秒”，并且在闰秒正式到来前逐步在自己的系统中加入毫秒。BT的语音时钟会在报时第三响之前加一秒的暂停。

Atomic time is constant, but the Earth’s rotation is gradually slowing down by around two thousandths of a second per day.

原子时间是恒定的，但是地球的自转速度每天大约会下降千分之二秒。

Leap seconds are therefore essential to ensuring civil time does not drift away from time based on the Earth's spin. If not corrected, such a drift would eventually result in clocks showing the middle of the day occurring at night.

所以，闰秒在保证民用时和自转时（依据地球自转而计算的时间）之间的一致性上起到了重要的作用。如果不更正二者之间的误差，最终会导致时钟在半夜的时候显示正午的时间。