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tz@iana.org

July 2024

15 participants
12 discussions

Mongolia
by Heitor David Pinto July 4, 2024

July 4, 2024

Hello, Sources about time zones in Mongolia seem to list one of two conflicting configurations. The first configuration, mentioned in a comment to the TZ database in 1999, citing a Mongolian government website, lists the provinces of Bayan-Ölgii, Khovd and Uvs in UTC+7, and the rest of the country in UTC+8. The second configuration, mentioned in a comment to the database in 2001, lists Bayan-Ölgii, Khovd, Uvs, Govi-Altai and Zavkhan in UTC+7, Dornod and Sükhbaatar in UTC+9, and the rest of the country in UTC+8. The first configuration is still mentioned by several Mongolian travel agencies: https://www.adventurerider.mn/en/page/about_mongolia http://www.naturetours.mn/nt/mongolia.php https://www.newjuulchin.mn/web/content/7506?unique=fa24a0f6e96e022a3578ee51… It also matches these flight schedules in 2013: http://web.archive.org/web/20130722023600/https://www.hunnuair.com/en/timet… The flight times imply that the airports of Uliastai (Zavkhan), Choibalsan (Dornod) and Altai (Govi-Altai) are in the same time zone as Ulaanbaatar, and Khovd is one hour behind. It also matches a Mongolian news article about the election in 2017: https://mongolia.gogo.mn/r/806d6 The second configuration was mentioned by an official of the Mongolian standards agency in an interview in 2014: https://ikon.mn/n/9v6 And it's still listed by the Mongolian aviation agency: https://ais.mn/files/aip/eAIP/2023-12-25/html/eSUP/ZM-eSUP-23-04-en-MN.html The TZ database used the first configuration until 2001, when it switched to the second configuration, under the assumption that its sources were more reliable. In 2008, based on sources indicating that Choibalsan actually used UTC+8, the database changed Dornod and Sükhbaatar to UTC+8, but only from 2008 on, and maintained Govi-Altai and Zavkhan in UTC+7. This resulted in a mix of the two configurations that is not supported as a whole by any source. Based on all the above sources, I believe that the first configuration is what is actually observed in Mongolia and has been so all along, at least since 1999. The second configuration closely matches the ideal time zone boundaries at 97.5°E and 112.5°E but it doesn't seem to be used in practice. So I suggest the following: 1. In zone.tab, remove Govi-Altai and Zavkhan from Asia/Ulaanbaatar, assuming that they have always used the same time as Ulaanbaatar, or create a new zone Asia/Uliastai showing Govi-Altai and Zavkhan in UTC+8 since at least 1999. 2. Remove the zone Asia/Choibalsan or make it an alias of Asia/Ulaanbaatar, assuming that it has always used the same time as Ulaanbaatar, or list its change from UTC+9 to UTC+8 since at least 1999 instead of 2008. Regards,Dave | | Virus-free.www.avg.com |

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error Portugal 1980
by Alois Treindl July 2, 2024

July 2, 2024

I think there is an error in TZ, regarding begin of DST in Portugal in 1980. A user of my website pointed it out. file europe has > Rule Port 1978 only - Oct 1 0:00s 0 - > Rule Port 1979 1982 - Sep lastSun 1:00s 0 - > Rule Port 1980 only - Mar lastSun 0:00s 1:00 S > Rule Port 1981 1982 - Mar lastSun 1:00s 1:00 S > Rule Port 1983 only - Mar lastSun 2:00s 1:00 S But Observatório Astronómico de Lisboa http://oal.ul.pt/hora-legal/legislacao-sobre-a-hora-legal/ has in document Tabela com a definição anual da Hora Legal portuguesa desde 1911 https://oal.ul.pt/documentos/2018/01/hl1911a2018.pdf > 1980 Hora do meridiano de Greenwich até à 1 hora do dia 6 de Abril, > instante > em que foi adiantada de 60 minutos, tendo-se regressado à hiora do meri- > diano de Greenwich às 2 horas do dia 28 de Setembro (Portaria nº 69/80) > I attach a patch file

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