Pacific Time Zone

The Pacific Time Zone is one of the four biggest time zones used in the United States and covers Los Angeles, which is the second biggest and most populous city in the whole of the U.S. with a population of around four million people. The Greater Los Angeles area, meanwhile, is the biggest metropolitan area in the entire time zone.

Before the introduction of time zones in the US, people would have to rely on the movement of the sun as their primary method of timekeeping. When the sun would cross over the meridian line, towns and cities would set their clocks to midday. This meant that time was completely different all over the country, without any standards or organization.

• Why was a standardized time system needed in the United States?
  • Initially, different local times were not a major issue.
  • However, as railroads and communication networks expanded, it became clear that a standardized system was necessary.
  • Train schedules were confusing because time varied from one town to the next.
  • Workers who relied on trains had no consistent schedules to follow.
• What was the first attempt at a time zone system?
  • Railroad authorities introduced their own time zones to solve the issue.
  • However, there were 100 different railroad time zones, which made the system overwhelming and difficult to follow.
• When were the four major time zones introduced?
  • To clarify timekeeping across the U.S., a new plan was implemented.
  • On November 18, 1883, four major time zones were introduced:
  • Pacific Time Zone
  • Mountain Time Zone
  • Central Time Zone
  • Eastern Time Zone
• Do all U.S. states follow a single time zone?
  • Some states cross over multiple time zones, while others are entirely within one.
  • For example, in the Pacific Time Zone:
  • California and Washington observe Pacific Time entirely.
  • However, only parts of Idaho, Nevada, and Oregon use Pacific Time.

The Pacific Time Zone, commonly abbreviated to PT, is the westernmost time zone used in the contiguous United States. There are two forms of Pacific Time: Pacific Standard Time (PST) and Pacific Daylight Time (PDT). PST is generally used in the US between November and March and is eight hours behind Coordinated Universal Time (UTC). PDT is used during periods of daylight saving time, which applies in the US from March to November, and is seven hours behind UTC.

The Pacific Time Zone extends to all of Nevada aside from a few small towns and communities, all of Oregon apart from one county, and the ten counties located in the Idaho Panhandle. Outside of the US, this time zone covers the Yukon area of Canada, as well as parts of British Columbia and one town in Canada's Northwest Territories. It also applies in the Baja California state of Mexico and Clarion Island, which is part of the Mexican state of Colima.

Daylight saving time was officially introduced in the US in 1966 with the Uniform Time Act, although the idea of changing the clocks during the summer months had been floated around as early as the late 18th century by Benjamin Franklin himself. Daylight savings helps to save energy and make the evening daylight last longer during the summer. When the Uniform Time Act came into effect on April 13 of 1966, time zones, including the Pacific Time Zone, were moved back an hour.

The Energy Policy Act of 2005 introduced an extension to daylight savings time periods from 2007 onwards. Daylight savings time originally occurred between the first Sunday of April to the last Sunday in October and has now been changed to last from the second Sunday of March to the first Sunday of November. All of the areas contained within the Pacific Time Zone, including the Canadian and Mexican zones, use the new dates for daylight savings time.