IANA time zone database

Abbreviations

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

Special abbreviations

• LMT - local mean time

Composing parts

position from right	Letter	Meaning	Occurrence
1	T	Time	always
2	D	Daylight (Saving) (DST 1:00)
2	S	Standard	several
2	S	Summer (DST 1:00)	europe file: e.g. BST British Summer Time, CEST Central European Summer Time
2	W	War	northamerica file: US and Mexico
2	P	Peace	northamerica file: US
2	M	Mean	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
2	M	Midsummer (DST 2:00)	europe file: Moscow - M # Midsummer, also for Spain, France, Germany/SovietZone
32	LM	Local Mean	several
32	DS	Double Summer (DST 2:00)	europe file: MDST # Moscow Double Summer Time, BDST - British Double Summer Time
32	DD	Double Daylight (Saving) (DST 2:00)	northamerica file: StJohns 1988)
32	HS	half summer time? (DST 0:30)	australasia file: Pacific/Rarotonga CK%sT and "HS"
32	HS	? (DST 0:20)	africa file: Rule Ghana 1936-1942
32	HD	half daylight saving time? (DST 0:30)	northamerica file: Rule Belize 1918-1942 northamerica file: Rule DR 1969-1973

Other:

Kampala:
3:00	-	EAT	1930
2:30	-	BEAT	1948
2:45	-	BEAUT	1957
Aruba (in ISO 3166-1 AW)
-4:00	-	AST

• 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)

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]	TZ coordinator (Paul Eggert) does not want to fix
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]	TZ coordinator (Paul Eggert) does not fix
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]	TZ coordinator (Paul Eggert) does not fix - reason unknown

Localization

CLDR

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

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