What is a time zone?

We explain what time zones are and why they are necessary. And as an example, list of time zones around the planet.

1. What is a time zone?

The time zone is a concept that comes from geography, and that consists of each of the twenty-four regions of chronometric time in which our planet is divided . Each of these regions is called the “time zone” or “time slot” and has a specific assigned time, which applies to all populations whose geographic location shares the same meridian.

Said in simpler terms, it is a division of the planet Earth in spindles (strips, columns) that allows us to calculate the time in each country of the world , adding or subtracting one hour (1 h) according to the amount of time zones that separate us from him. For example, if there are three time slots between a country X and a country Y, it will be necessary to add or subtract three hours while registering the clocks of one, to determine the exact time of the other.

The system arises because the Earth rotates on its axis from west to east, causing the Sun to illuminate a portion while leaving the other in the dark, and a method is necessary to standardize time . Thus arose the Coordinated Universal Time (UTC), corresponding to the “zero meridian”: the Royal Greenwich Observatory in England, United Kingdom (UK).

Said “universal” time is accepted by convention and serves to determine the others, adding or subtracting hours as they are, respectively, further east or west of this time zone (0). In the same way, the 180 ° meridian is considered in this system the international date change line , that is, the point at which the day ends and a new one is born.

The time zones are a guide, a reference for time management in a world in which we can move quickly through its surface. Each nation on the planet has chosen the time zone to govern , often determined by the one corresponding to its capital.

Some particularly voluminous nations handle more than one time zone, such as the United States, Russia, Australia or Canada, as they are crossed by several meridians. In other cases, nations alternate between one and another time zone, according to the weather station in which they are located, to make the most of the limited or abundant hours of daylight, and thus save electricity .

Time zones are traditionally denoted by the acronym UTC and the corresponding addition or subtraction of the hours of separation from the zero meridian.

2. Examples of time zones

Below is a partial list of time zones and the nations that choose them:

• UTC – 12 . Howland and Baker Islands (United States).
• UTC – 11 . American Samoa.
• UTC – 10 . Hawaii, French Polynesia, Cook Islands (New Zealand).
• UTC – 9:30 . Marquesas Islands (French Polynesia). 
• UTC – 9 . Continental Alaska, Gambier Islands (French Polynesia).
• UTC – 8 . Canada, United States (west), Mexico.
• UTC – 7 . Canada, United States (west-central), Mexico.
• UTC – 6 . Belize, Canada, Chile, Costa Rica, Ecuador (insular), El Salvador, United States (center-east), Guatemala, Honduras, Mexico, Nicaragua.
• UTC – 5 . Bahamas, Brazil, Canada, Colombia, Cuba, Ecuador (continental), United States (east), Haiti, Jamaica, Panama, Peru, Cayman Islands.
• UTC – 4 . Antigua and Barbuda, Barbados, Bolivia, Brazil, Canada, Dominican Republic, Dominica, Greenland, Grenada, Guyana, the Netherlands Antilles, Paraguay, Puerto Rico, Trinidad and Tobago, Venezuela.
• UTC – 3 . Argentina, Brazil, Chilean Antarctica, Greenland, French Guyana, Falkland Islands, Suriname, Uruguay.
• UTC – 2 . Brazilian coast, Sandwich Islands (United Kingdom).
• UTC – 1 . Greenland, Cape Verde, Azores Islands (Portugal).
• UTC 0 . Burkina Faso, Ivory Coast, Canary Islands (Spain), Ghana, Ireland, Iceland, Liberia, Morocco, Portugal, United Kingdom (England, Scotland, Wales, Northern Ireland), Senegal, Togo.
• UTC + 1 . Germany, Albania, Bosnia and Herzegovina, Belgium, Cameroon, Austria, Spain, Slovenia, Denmark, France, Hungary, Macedonia, Italy, Nigeria, Norway, Netherlands, Czech Republic, Vatican City, Tunisia, Switzerland, Sweden.
• UTC + 2 . Bulgaria, Botswana, Jordan, Israel, Finland, Egypt, Estonia, Palestine, Namibia, Libya, Rwanda, Romania, Syria, South Africa, Ukraine, Zimbabwe.
• UTC + 3 . Saudi Arabia, Belarus, Qatar, Ethiopia, Iraq, Kenya, Kuwait, Madagascar, Russia (west), South Sudan, Turkey, Yemen.
• UTC + 3:30 . Iran.
• UTC + 4 . Armenia, United Arab Emirates, Russia (center-west), Oman.
• UTC + 4:30 . Afghanistan.
• UTC + 5 . Kazakhstan, Pakistan, Maldives, Russia (center-east).
• UTC + 5:30 . India, Sri Lanka.
• UTC + 5:45 . Nepal.
• UTC + 6 . Bangladesh, Kyrgyzstan, Russia (Omsk only).
• UTC + 6:30 . Cocos Islands (Australia) and Burma.
• UTC + 7 . Cambodia, Indonesia, Laos, Mongolia, Russia (east), Thailand, Vietnam.
• UTC + 8 . Australia (west), Brunei, China, island Indonesia, Malaysia, Philippines, Singapore, Russia (far east).
• UTC + 8:30 . North Korea.
• UTC + 9 . South Korea, Japan, Palau, East Timor, Russia (yes, it is huge).
• UTC + 9:30 . Australia (center).
• UTC + 10 . Australia (east), Micronesia, Russia (insular region).
• UTC + 11 . Vanuatu, Papua New Guinea, Solomon Islands, Russia (Far East).
• UTC + 12 . Fiji, Nauru, New Zealand and the latest from Russia.
• UTC + 13 . Tonga, Tokelau, Samoa.
• UTC + 14 . Kiribati