▉▉▉▉ Pale colours: Standard time observed all year ▉▉▉ Dark colours:Summer time observed
UTC+00:00 is an identifier for atime offset from UTC of +00:00. This time zone is the basis ofCoordinated Universal Time (UTC) and all other time zones are based on it. InISO 8601, an example of the associated time would be written as 2069-01-01T12:12:34+00:00. It is also known by the following geographical or historical names:
The westernmost point where UTC with DST is applied isEl Hierro,Canary Islands, Spain (18°00′ W). Time used there is 2 hours and 12 minutes ahead of physical time in the summer, making for the greatest discrepancy in the UTC time zone.
The easternmost settlement where UTC with DST is applied isLowestoft inSuffolk,East Anglia, UK (at just 1°45′ E).
Morocco normally observesUTC+01:00, but the clock is set back one hour duringRamadan. SeeTime in Morocco for further information.
Whilstde facto Ireland operates on the same time as the United Kingdom, itsde jure basis to do so differs. Whereas standard time in the UK is GMT in winter andBST (daylight saving time) in summer,Irish Standard Time (UTC+01:00) is observed in summer and GMT is used in winter. For details, see below.
As daylight saving time (Northern Hemisphere summer)
The westernmost point where UTC with no DST is applied isBjargtangar, at the northwest peninsula ofIceland (24°32′ W). Time used there is 1 hour and 38 minutes ahead of physical time. This is the greatest deviation from physical time for UTC+00:00 with no DST.
Discrepancies between use of UTC+00:00 as standard time rather than local solar time
Since legal, political, social and economic criteria, in addition to physical or geographical criteria, are used in the drawing of time zones, actual time zones do not precisely adhere to meridian lines. The UTC+00:00 time zone, were it determined purely bylongitude, would consist of the area between meridians 7°30′W and 7°30′E. However, in much of Western and Central Europe, despite lying between those two meridians, UTC+01:00 is used; similarly, there are European areas that use UTC, even though their physical time zone isUTC−01:00 (e.g. most of Portugal), orUTC−02:00 (the westernmost part of Iceland). Because the UTC+00:00 time zone in Europe is at its western edge,Lowestoft in the United Kingdom, at only 1°45′E, is the easternmost settlement in Europe in which UTC+00:00 is applied.
Countries and areas west of 22°30′W ("physical" UTC−02:00) that use UTC+00:00
The westernmost part of Iceland, including the northwestpeninsula (the Westfjords) and its main town ofÍsafjörður, which is west of 22°30′W, uses UTC+00:00.Bjargtangar, Iceland is the westernmost point in which UTC is applied.
Countries and areas west of 7°30′W ("physical" UTC−01:00) that use UTC+00:00
Most of Portugal, includingLisbon,Porto,Braga,Aveiro, andCoimbra. (Only the easternmost part, including cities such asBragança andGuarda, lies east of 7°30′W.)Madeira, at 17°W even further west, also employs UTC+00:00.
The western half of Ireland, including the cities ofCork,Limerick, andGalway
Extreme westerly portion of theOuter Hebrides, in the west ofScotland; for instance,Vatersay, an inhabited island and the westernmost settlement ofGreat Britain, lies at 7°54′W. Ifuninhabited islands or rocks are taken into accountSt Kilda, west of the Outer Hebrides, at 8°58′W, andRockall, at 13°41′W, should be included.
Spain (except for the Canary Islands, which use UTC+00:00). Much ofGalicia (and far western fringes ofExtremadura andAndalusia) lie west of 7°30′W ("physical" UTC−01:00), whereas there is no Spanish territory that even approaches 7°30′E (the boundary of "physical" UTC+01:00). Spain's time is the direct result ofGeneralissimo Franco's presidential order (published inBoletín Oficial del Estado of 8 March 1940)[3] abandoning Greenwich Mean Time and advancing clocks one hour, effective from 23:00 on 16 March 1940. This is an excellent example of political criteria used in the drawing of time zones: the time change was passed "in consideration of the convenience from the national time marching in step according to that of other European countries".[4][5] The presidential order (most likely enacted to be in synchrony withNazi Germany andFascist Italy[citation needed], with which theFranco regime was unofficially allied) included in its 5th article a provision for its future phase out,[5] which never took place. Due to this political decision, Spain is two hours ahead of itslocal mean time during the summer, one hour ahead in winter.[6]
