[tz] Time zone abbreviations

[Paul Goyette]

On Sat, 7 Sep 2019, Alois Treindl wrote:

> I think the change was made because many abbreviations were ambiguous.
> In the US, AST is commonly used for Standard Alaska Time, 10h west of GMT.
>
> See the entry in file NEWS of Release 2017a - 2017-02-28 00:05:36 -0800

The majority of these zones were changed to eliminate zone abbreviations
that were invented by the TZ project itself, rather than resulting from
any real-world usage.  As I remember, ambiguity was not a factor (as
there are still ambiguous abbreviations today).

>
>> Â  Changes to past and future time zone abbreviations
>> 
>> Â Â Â  Switch to numeric time zone abbreviations for South America, as
>> Â Â Â  part of the ongoing project of removing invented abbreviations.
>> Â Â Â  This avoids the need to invent an abbreviation for the new Chilean
>>     new zone.  Similarly, switch from invented to numeric time zone
>> Â Â Â  abbreviations for Afghanistan, American Samoa, the Azores,
>> Â Â Â  Bangladesh, Bhutan, the British Indian Ocean Territory, Brunei,
>> Â Â Â  Cape Verde, Chatham Is, Christmas I, Cocos (Keeling) Is, Cook Is,
>> Â Â Â  Dubai, East Timor, Eucla, Fiji, French Polynesia, Greenland,
>> Â Â Â  Indochina, Iran, Iraq, Kiribati, Lord Howe, Macquarie, Malaysia,
>> Â Â Â  the Maldives, Marshall Is, Mauritius, Micronesia, Mongolia,
>> Â Â Â  Myanmar, Nauru, Nepal, New Caledonia, Niue, Norfolk I, Palau,
>>     Papua New Guinea, the Philippines, Pitcairn, Qatar, Réunion, St
>> Â Â Â  Pierre & Miquelon, Samoa, Saudi Arabia, Seychelles, Singapore,
>> Â Â Â  Solomon Is, Tokelau, Tuvalu, Wake, Vanuatu, Wallis & Futuna, and
>> Â Â Â  Xinjiang; for 20-minute daylight saving time in Ghana before 1943;
>> Â Â Â  for half-hour daylight saving time in Belize before 1944 and in
>> Â Â Â  the Dominican Republic before 1975; and for Canary Islands before
>> Â Â Â  1946, for Guinea-Bissau before 1975, for Iceland before 1969, for
>> Â Â Â  Indian Summer Time before 1942, for Indonesia before around 1964,
>> Â Â Â  for Kenya before 1960, for Liberia before 1973, for Madeira before
>> Â Â Â  1967, for Namibia before 1943, for the Netherlands in 1937-9, for
>> Â Â Â  Pakistan before 1971, for Western Sahara before 1977, and for
>> Â Â Â  Zaporozhye in 1880-1924.
>> 
>> Â Â Â  For Alaska time from 1900 through 1967, instead of "CAT" use the
>> Â Â Â  abbreviation "AST", the abbreviation commonly used at the time
>>     (Atlantic Standard Time had not been standardized yet).  Use "AWT"
>> Â Â Â  and "APT" instead of the invented abbreviations "CAWT" and "CAPT".
>
> On 07.09.19 07:15, Elena Sharovar wrote:
>> Hi Iana Team,
>> 
>> where can I find some explanation why in 2017a format changed from AST to 
>> +03?
>> and the same happened in a lot of timezones (letter abbreviations changed 
>> to +03, +02, etc.)
>> 
>> // 2016j
>> Zone Asia/Riyadh 3:06:52 - LMT 1947 Mar 14
>> 3:00 -*AST*
>> 
>> // Â 2017a
>> Zone Asia/Riyadh 3:06:52 - LMT 1947 Mar 14
>> 3:00 - *+03*
>> 
>> Thanks & Regards,
>> Elena.
>
>
> !DSPAM:5d7378ac119021727852487!
>

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