Time zones - Fusos horários

This is an article from travel tips.

World time zones. Click to view larger.

This is a list of countries, regions and territories grouped by time zone.

Although many time zones have descriptive names used by people themselves, they are less ambiguously identified by their relationship to the UTC (Coordinated Universal Time; English: Universal Time, Co-ordinated). UTC used to be called GMT (Greenwich Mean Time), after the Royal Observatory located in the area of Greenwich in London.

UTC is also sometimes called Z or time Zulu (Zulu team). A tense can be written as e.g. 21:45 Z with Z indicating UTC. The "Z" stands for "zero", and "Zulu" is the two-way radio pronunciation of "Z". It comes from the nautical system in which each time zone has been assigned a letter.

Time zones east of UTC and west of the International Date Line are specified by the number of hours ahead of UTC (eg UTC 4); zones west of UTC and east of the Date Line are specified by the number of hours behind UTC (eg UTC-6). Crossing the Date Line going east, the clocks get a total of 24 hours, and vice versa in the opposite direction. the east to keep certain national island groups on the same calendar day even though they are not within a single time zone).

Travel across time zones

You need to take some precautions when planning trips that span time zones, for example:

• Your "biological clock" may experience some stress as you "say" to meet business appointments, outings and other obligations perhaps a few or several hours different from the hours you usually rest.
• You can miss important obligations simply because you don't understand what the correct local time will be when you travel.
• Crossing the International Date Line can cause confusion about what date you will arrive, for example:
  • Starting a 12-15 hour flight from the US west coast to Japan or Hong Kong at the end of the night you can disembark there in the morning, two days later.
  • If you start the reverse course at noon, you might as well get there, but a few clock hours more or less on the same calendar day.

If you travel, have time zone complexities or possible impacts on your health or comfort, consult an expert when you plan.