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Time in Alaska

From Wikipedia, the free encyclopedia

Alaska is officially covered by two time zones - the Alaska Time Zone and the Hawaii–Aleutian Time Zone. The Hawaii–Aleutian Time Zone is used for the Aleutian Islands west of 169°30′W (Islands of Four Mountains, Andreanof Islands, Rat Islands and Near Islands),[1] and the rest of the state uses the Alaska Time Zone.[2] The entirety of Alaska observes daylight saving time.

The town of Hyder, because it essentially is a single town split by the border between the United States and Canada, unofficially observes Pacific Time including DST (UTC−08:00, DST UTC−07:00) like its neighbor Stewart, British Columbia, with the exception of the U.S. Post Office (because it is a federal facility).[3][4][5]

History

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As part of Russian America, Alaska used the Julian calendar and followed the same day of the week as Asia, using the date of the eastern hemisphere. In 1867, Alaska became a United States territory (through the Alaska Purchase) and began using the Gregorian calendar, aligning with the same day of the week as the Americas, using the date of the western hemisphere. The switch was achieved by repeating the same day of the week and skipping eleven days of the month instead of twelve during the 19th century, so that the purchase date of Friday, October 6 (Julian) was followed once again by Friday, October 18 (instead of Saturday, October 19 in Gregorian).[6] That change redrew the International Date Line from being east to west of the territory to realign itself from Asian to American dates, thus shifting it from the date of the eastern hemisphere to the western hemisphere.

Before time zones were introduced, every place used local observation of the sun to set its clocks, which meant that every location used a different local mean time based on its longitude. For example, Sitka, the capital of Alaska at the time, at longitude 135°20′W, had a local time equivalent to UTC+14:59 under Russia and UTC−09:01 under the United States.[7]

In 1900, "Alaska Standard Time" was established within the state as UTC−09:00.[8]

In 1918, the United States Congress passed the Standard Time Act, which defined a standard time zone for Alaska - United States Standard Alaska Time, set at UTC−10:00.[9]

On January 20, 1942, all of the United States, including Alaska, began to observe War Time.[10] Standard time in the United States advanced by one hour and would remain so until September 25, 1945, when the act was repealed.[11]

In 1966, Congress passed the Uniform Time Act. The Uniform Time Act introduced Daylight Saving Time uniformly in the United States, which Alaska would begin observing on April 28, 1968.[12][13] The Uniform Time Act also defined four time zones that Alaska would use:[14]

In April 1983, the Alaska Legislature approved a resolution asking the Department of Transportation to switch Alaska to use only two time zones.[19] It was approved by Secretary of Transportation Elizabeth Dole on September 15, 1983, and took effect on October 30, 1983.[20][21] Areas east of Unalaska began using the Yukon Time Zone (UTC−09:00). Most of the Aleutian Islands, previously on Bering Time, were now using Alaska–Hawaii Time.[22] As an act of Congress was required to change the name of the time zones,[23] the time zones did not gain their modern names (Alaska Time and Hawaii–Aleutian Time) until November 30, 1984.[24]

Historic alterations

[edit]
Period in use Time offset from GMT/UTC[a] Name of time
Wednesday, July 15, 1741 – Friday, October 6, 1867 (Julian Calendar) GMT+14:59 (in Sitka) Local Mean Time
GMT+12:24 (in Aleutian Islands)
Friday, October 18, 1867 – 1900 (Gregorian Calendar) GMT−09:01 (in Sitka) Local Mean Time
GMT−11:36 (in Aleutian Islands)
1900 – 1918 GMT−09:00 (including Aleutian Islands) Alaska Standard Time
1918 – January 19, 1942 GMT−08:00 (Panhandle Areas) Pacific Standard Time
GMT−09:00 (in Yakutat) Yukon Standard Time
GMT−10:00 Alaska Standard Time
GMT−11:00 (Nome, and Aleutian Islands) Bering Standard Time
January 20, 1942 – September 30, 1945 GMT−07:00 (Panhandle Areas) Pacific War Time
GMT−08:00 (in Yakutat) Yukon War Time
GMT−09:00 Alaska War Time
GMT−10:00 (Nome, and Aleutian Islands) Bering War Time
September 30, 1945 – March 31, 1967 GMT−08:00 (Panhandle Areas) Pacific Standard Time
GMT−09:00 (in Yakutat) Yukon Standard Time
GMT−10:00 Alaska Standard Time
GMT−11:00 (Nome, and Aleutian Islands) Bering Standard Time
April 1, 1967 – October 30, 1983 GMT/UTC−08:00 (Panhandle Areas) Pacific Standard Time
GMT/UTC−09:00 (in Yakutat) Yukon Standard Time
GMT/UTC−10:00 Alaska–Hawaii Standard Time
GMT/UTC−11:00 (Nome, and Aleutian Islands) Bering Standard Time
October 30, 1983 – present UTC−09:00 (in Juneau) Alaska Time Zone
UTC−10:00 (in Aleutian Islands) Hawaii–Aleutian Time Zone
2007 − present UTC−08:00 (except in Aleutian Islands) Alaska Daylight Time

tz database

[edit]

The tz database version 2024b contains seven time zones for Alaska for historical reasons. Only three (America/Adak, America/Anchorage, and America/Metlakatla) are currently in use.

CC Coordinates TZ Comments UTC offset UTC offset DST Notes
US +611305−1495401 America/Anchorage Alaska (most areas) −09:00 −08:00
US +581807−1342511 America/Juneau Alaska - Juneau area −09:00 −08:00
US +571035−1351807 America/Sitka Alaska - Sitka area −09:00 −08:00
US +593249−1394338 America/Yakutat Alaska - Yakutat −09:00 −08:00
US +643004−1652423 America/Nome Alaska (west) −09:00 −08:00
US +515248−1763929 America/Adak Alaska - western Aleutians −10:00 −09:00
US +550737−1313435 America/Metlakatla Alaska - Annette Island −09:00 −08:00

Notes

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  1. ^ The term UTC (Coordinated Universal Time) begin in use just after the introduction of Unix Time on January 1, 1970. In those days before 1970, the GMT (Greenwich Mean Time) was the term being used.

References

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  1. ^ "eCFR :: 49 CFR 71.12 - - Hawaii-Aleutian zone". Code of Federal Regulations. Retrieved October 18, 2022.
  2. ^ "eCFR :: 49 CFR 71.11 - - Alaska zone". Code of Federal Regulations. Retrieved October 18, 2022.
  3. ^ "Exceptions, Oddities and Notes". OnTimeZone.com. Retrieved June 17, 2012.
  4. ^ Bohrer, Becky (April 26, 2021). "Dunleavy shares COVID vaccine with Canadian town". Alaska Public Media. Retrieved October 25, 2022.
  5. ^ Levin, Dan (July 4, 2016). "In Hyder, roaming grizzlies, no police and large doses of Canada". Anchorage Daily News. Retrieved August 12, 2023.
  6. ^ Dershowitz, Nachum; Reingold, Edward M. (2008). Calendrical Calculations. Cambridge University Press. p. 47. ISBN 9780521885409.
  7. ^ Time Zone in Sitka, Alaska, USA, Timeanddate.com.
  8. ^ "Keeping Time in Alaska: National Directives, Local Response | Alaska Historical Society". Alaska Historical Society. Retrieved October 20, 2022.
  9. ^ Standard Time Act of 1918. 40 Stat. 450
  10. ^ AN ACT To promote the national security and defense by establishing daylight saving time. 56 Stat. 9
  11. ^ AN ACT To provide for termination of daylight saving time. 59 Stat. 537
  12. ^ a b Time Zone in Anchorage, Alaska, USA, Timeanddate.com.
  13. ^ "Daylight Savings Time Comes To Alaska Soon". The Daily Sitka Sentinel. April 22, 1968. Alaskans will advance their clocks one hour next Sunday as the state for the first time observes Daylight Savings Time.
  14. ^ Uniform Time Act of 1966. Pub. L. 89–387, 80 Stat. 107, enacted April 13, 1966
  15. ^ Time Zone in Nome, Alaska, USA, Timeanddate.com.
  16. ^ Time Zone in Adak, Alaska, USA, Timeanddate.com.
  17. ^ Time Zone in Yakutat, Alaska, USA, Timeanddate.com.
  18. ^ Time Zone in Juneau, Alaska, USA, Timeanddate.com.
  19. ^ "Alaska Asks for Reduction Of Time Zones". The Daily Sitka Sentinel. Associated Press. April 20, 1983.
  20. ^ Spencer, Hal (September 16, 1983). "Most of Alaska to Switch to a Common Time Zone". The Daily Sitka Sentinel.
  21. ^ "AROUND THE NATION; Most of Alaska to Go Under One Time Zone". The New York Times. September 18, 1983. Retrieved October 18, 2022.
  22. ^ Wallace Turner (November 1, 1983). "Alaska's four time zones now two". The New York Times. Retrieved September 21, 2017. The big change was in Juneau, Ketchikan and Sitka, the major towns in southeast Alaska, where clocks shifted back two hours to Yukon time. After decades on Pacific time, this region will now be an hour earlier, as will Anchorage and Fairbanks, which formerly were two hours earlier than Pacific time.
  23. ^ Hal Spencer (September 16, 1983). "Most of Alaska to Switch to a Common Time Zone". The Daily Sitka Sentinel.
  24. ^ Supplemental Appropriations Act, 1984. Section 2003. 97 Stat. 1153
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