- Alaska Time Zone
The Alaska Time Zone observes
standard time by subtracting nine hours fromCoordinated Universal Time (UTC-9 ). Duringdaylight saving time itstime offset is only eight hours (UTC-8 ). The clock time in this zone is based on themean solar time of the 135th degree meridian west of theGreenwich Observatory .The zone includes nearly all of the U.S. state of
Alaska and is one hour behind thePacific Time Zone .*standard time: Alaska Standard Time (AKST)
*daylight saving: Alaska Daylight Time (AKDT)The western Aleutians observe Hawaii-Aleutian Time, one hour behind the remainder of the state.
Effective 2007, the local time changes from AKST to AKDT at 02:00 LST to 03:00 LDT on the second Sunday in March and returns at 02:00 LDT to 01:00 LST on the first Sunday in November.
History
The original Alaska time zone was actually known as Alaska-Hawaii Standard Time Zone; that zone is now known as Hawaii-Aleutian Time Zone.
The Alaska Time Zone is the same as what the
Yukon Standard Time Zone (YST) was. However, the Yukon Territory switched to thePacific Standard Time Zone in 1975 and the time zone was not used (except for Yakutat) until 1983 when the state of Alaska decided to move most of the state to UTC-9. Prior to that theAlaska Panhandle communities were on the Pacific Time Zone, while most of the interior was onUTC-10 . Nome and the Aleutians previously observed Bering Standard Time orUTC-11 .Anomalies
The Alaska Time Zone is applied to the territory of the state of
Alaska to the east of 169°30′ W. Given that the UTC−9 time corresponds to the solar time at 9 × 15° = 135° W (roughly, Juneau), the westernmost locales where Alaska time gets applied are off by 169°30′ − 135° = 34°30′ from their 'physical' time. This means that when a clock correctly set to Alaskan time, at a location just east of 169°30′ W, shows noon, the 'physical' time is actually just 9:42 am. When UTC−8 is applied in the summer, this effect becomes even more apparent, since the solar time atFresno, California (about 120° W) is used. At a (say) July noon, the physical time at the extreme westerly points of the Alaskan time zone will actually be only 8:42 a.m. Very few people however, notice this as these locations are virtually uninhabited, and for the very few people who do live there, the long days in the summer and short days in the winter make the sunrise and sunset times less important than areas closer to the equator. In Juneau,solar noon can occur as much as 17 minutes before "noon" clock time.In Anchorage, visitors from more southerly latitudes are often surprised to see the sun set at 11:41 pm on the summer
solstice , but the actual 'physical time' is 9:41 pm. This is because at 150° W, Anchorage is a full solar hour behind the legal time zone and observes daylight saving time as well. Some local residents refer to this phenomenon as "double daylight time". In Fairbanks, the same circumstances cause sunset to occur at 12:47 am on the next calendar day. In the winter, even without daylight saving time, another anomaly is that on the winter solstice in Nome, the sunrise is actually after "noon" clock time, at 12:02 pm lasting for about 3 hours before sunset.Major Metropolitan Areas
*
Anchorage, Alaska ee also
*
Time zone Sources
* [http://www.time.gov/timezone.cgi?Alaska/d/-9/java The official U.S. time for the Alaska Time Zone]
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