longitude in time

基本解释

GMT is a universal time zone, based on the Greenwich meridian corrected by the longitude of the location in which the time is set.
GMT是一种通用时区，是根据格林威治子午线，用设定时间所在位置的经度与其求差计算出来的。
Different countries in the world where the longitude location, the time of all countries are different, so the "new year" date is different.
世界各国所处的经度位置不同，各国的时间也不同，所以各国“过年”的日期也不同。
Because of the longitude of the world in different locations, countries of time is also different, accordingly, "new date there are also different."
由于世界各国所处的经度地位不同，各国的时间也不同，因而，“除夕”的日期也有不同。

The clock could tell the correct time in two places, meeting the requirements for learning longitude on the sea.

As a seafaring nation, Britain depended on accurate navigation, and determining longitude on the open ocean depended on comparing local time to the time in a place where the longitude was known.
FORBES: Magazine Article
For on-location shooters, landscape photographers or enthusiast photo travelers, the EOS 6D features a built-in GPS receiver to record longitude, latitude, elevation and Coordinated Universal Time (UTC) as EXIF data for seamless geo-tagging while shooting.
ENGADGET: Canon unveils EOS 6D DSLR: full frame sensor and WiFi for $2,099 in December