IANA time zone database

Abbreviations

• proposal to change to Internationalized time point unique time zone abbreviations at http://mm.icann.org/pipermail/tz/2012-October/018362.html

Components that specify a location

• Sometimes the ISO 3166-1 alpha-2 country code (cc) is used, then the format often is ccT.
• Two letters for locality - xxT
  • Brazil - Fernando Noronha: FNT
• Two letter for locality - xxST
  • Lord Howe : LHST
• Two letters for locality - xx%sT
  • Several zone in Brazil that use Brasilia BRT (BR is also the country code)

Other:

Kampala:
3:00	-	EAT	1930
2:30	-	BEAT	1948
2:45	-	BEAUT	1957
Aruba (in ISO 3166-1 AW)
-4:00	-	AST
GBGT	1966 May 26 # Br Guiana Time
NEGT	1975 Nov 20 # Dutch Guiana Time

Components that do not specify a location

position from right	Letter	Meaning	Save	Occurrence
1	T	Time	N/A	always
2	D	Daylight (Saving)	1:00	several
2	S	Standard	N/A	several
2	S	Summer	1:00	europe file: e.g. BST British Summer Time, CEST Central European Summer Time
2	W	War	1:00	northamerica file: US and Mexico
2	P	Peace	1:00	northamerica file: US
2	M	Mean	N/A	africa file: LMT # Lisbon Mean Time, FMT # Freetown Mean Time, PMT # Paris Mean Time europe file: MMT # Moscow Mean Time southamerica file: CMT # Cordoba Mean Time, CMT # Calamarca MT(!), QMT # Quito Mean Time, BMT # Bogota Mean Time, SMT # Stanley Mean Time, SMT # Santiago Mean Time, MMT # Montevideo MT(!), PMT # Paramaribo Mean Time, CMT # Caracas Mean Time
2	M	Midsummer	2:00	europe file: Moscow - M # Midsummer, also for Spain, France, Germany/SovietZone
32	LM	Local Mean	N/A	several
32	DS	Double Summer	2:00	europe file: MDST # Moscow Double Summer Time, BDST - British Double Summer Time
32	DD	Double Daylight (Saving)	2:00	northamerica file: StJohns 1988)
32	HS	Half Summer	0:30	australasia file: Pacific/Rarotonga CK%sT and "HS" southamerica file: Uruguay
32	HS	Half Summer	0:20	africa file: Rule Ghana 1936-1942
32	HD	Half Daylight (Saving)	0:30	northamerica file: Rule Belize 1918-1942 northamerica file: Rule DR 1969-1973

Bugs

Some fixes can be found at ANNA time zone database.

Country	Description	Open since at least	Why not fixed?
Australia	EST and CST are used as acronyms for AEST/AEDT and CEST/CEDT, i.e. during DST one cannot tell from the acronym what zone is meant.	2006-06-02 04:08:36 [1]	under consideration
Indonesia	WIT means Western Indonesian Time, but in local Indonesian language, WIT stands for Waktu Indonesia Timur (Eastern Indonesian Time), change requests - without mentioning the ambiguity - go back to 2003 [2]	2013-02-13 14:17:58 [3]
Norway	No IANA zone defined for Bouvet Island while Norwegian law sets a standard time http://article.gmane.org/gmane.comp.time.tz/5218/	2012-05-29 18:32:23 [4]	TZ coordinator (Paul Eggert) does not want to fix
Russia	Zones in Siberia are wrong patch provided 2012-05-02 22:18:43 by Arthur David Olson [5]	2011-09-17 16:12:16 [6]	2013-04-18 under consideration
Australia	tzid Antarctica/Macquarie is listed for Antarctica, but it is not near the landmass, and not even in the oceanic region included in the Antarctic Treaty. Suggested fix: Pacific/Macquarie. Bug introduced ca 2010 [7]	2013-04
French Southern and Antarctic Land	Zone missing: http://mm.icann.org/pipermail/tz/2012-May/017804.html	2012-05-12 [8]

Zone renaming

• Alma-Ata->Almaty https://github.com/eggert/tz/commit/ef92aeaad41598210a2d973fd653bed48166f913#zone.tab
• Ulan_Bator->Ulaanbaatar https://github.com/eggert/tz/commit/377789bf6b7491c661f2abd274ead292e20aa2d5#zone.tab
• Thimbu->Thimphu, Ashkhabad->Ashgabat https://github.com/eggert/tz/commit/5fc6f6d97aba126b82e203373037ff0ddb77291e#zone.tab
• Dacca->Dhaka https://github.com/eggert/tz/commit/d2a2377eb277c4185255248d7436363ce662e046#zone.tab
• Porto_Acre->Rio_Branco https://github.com/eggert/tz/commit/b4823fa8d676cc4b72ca89a085358e17d18106a6#zone.tab
• Macao->Macau https://github.com/eggert/tz/commit/0594b59cdab15ff1dcccdb64bcb6b32bc096fb5d#zone.tab
• Ujung_Pandang->Makassar https://github.com/eggert/tz/commit/59b22c72fd2ffe9245b269cb9634a9ccb6f89c18#zone.tab
• /Argentina/ https://github.com/eggert/tz/commit/86ca028348fee535690202b5cbb73f93673cf2e2#zone.tab
• Coral_Harbour->Atikokan https://github.com/eggert/tz/commit/2436b01841ed68e63d5f72a2c1cacbce116a73d0#zone.tab
• Asmera->Asmara https://github.com/eggert/tz/commit/f7e6fba9999a45a8baf73b5b1aac139df99bf956#zone.tab
• Faeroe->Faroe https://github.com/eggert/tz/commit/e35b3358118ab6b2529a55e6d162a602f9dcf6d8#zone.tab
• Saigon->Ho_Chi_Minh https://github.com/eggert/tz/commit/6dfed6b7a0b4fc3ec96d36aba9cd6fc0153b362a#zone.tab
• Calcutta->Kolkata https://github.com/eggert/tz/commit/6ce4c9420f6746d9e06269a80381af29c555c558#zone.tab
• Kathmandu->Katmandu https://github.com/eggert/tz/commit/27bdceb8d4a40bf01ad30592e5c0b9060720c319#zone.tab
• Truk->Chuuk, Ponape->Pohnpei https://github.com/eggert/tz/commit/67b1c5f6929c1562ea68a5716ca136c0ee42b252#zone.tab

Removal

• Ensenada
  • https://github.com/eggert/tz/commit/3d8ce2fa1dcdd23a753ffc6dd5a7ebcefbfff92d#zone.tab
  • https://github.com/eggert/tz/commit/62250927e3cace5efd873f7817b363cb9d1588be#zone.tab
• ComodRivadavia https://github.com/eggert/tz/commit/63136721d64f6b5af8328f567c53308fa7e7f7c4#zone.tab
• Jan Mayen https://github.com/eggert/tz/commit/98c2234160bcc8d0045c67c3567ed2e916a0b356#zone.tab
• Geneva https://github.com/eggert/tz/commit/1d07c84f7a09468e16dc45df6cb0cf2bb8c59f2a#zone.tab
• Kashi, Wulumuqui https://github.com/eggert/tz/commit/b5a5341f46c01bd35cd9ba110b959c14d174de0a#zone.tab
• Tiraspol https://github.com/eggert/tz/commit/d7cc3a8a401b67dcb563f2bcf0c034f84b22e277#zone.tab

Localization

CLDR

http://unicode.org/repos/cldr/trunk/common/supplemental/metaZones.xml

• territory 001 - might refer to the UN M.49 code for "World".