January 2021 - tz - lists.iana.org

Re: [tz] CCTF survey on Time and Frequency Metrology - Telecom
by Gertsvolf, Marina Jan. 25, 2021

Jan. 25, 2021

Dear Colleague, The last time the definition of the SI second was changed was in 1967 when Caesium atom hyperfine frequency transition was chosen as the reference value. Since then first the primary thermal beam caesium clocks and then caesium fountains have been providing the SI second realization values to steer the International Atomic Timescale. The current fountain uncertainties are at the low 1E-16 level. The frequency metrology research in recent years has surpassed the microwave clocks, and optical frequency standards based on trapped ions and atoms now provide frequency measurements with evaluated uncertainties at the level 1E-18. The frequency comparisons have also been advancing both through improved techniques in Global Navigation Satellite Systems signal analysis and the Two Way satellite Time and Frequency transfer as well as with fibre based frequency links and portable optical clocks. Frequency combs used to compare frequencies between clock lasers of different optical clocks and also between optical frequencies and microwave 133Cs frequency of 9.192631770 GHz are now routine laboratory equipment and are commercially readily available. These factors now provide a solid foundation to prepare for the redefinition of SI second based on the optical frequency standard. The exact approach is currently under discussion and it may be selecting one atomic candidate or building an ensemble. The specific requirements and the conditions for the redefinition to take place are also being finalized. The Consultative Committee for Time and Frequency (CCTF) has started preliminary work on this subject, to investigate possible scenarios and their possible impact. It is within this framework that we contact you an expert in the field of Telecommunications, in order to make sure that the needs and wishes of your community are integrated into the general debate that will take place and may, eventually, lead to the redefinition of the second. With the new definition, the frequency measurement accuracy will surpass that of Caesium-based timescale by at least one order of magnitude and will provide an adequate tool for current and future research into fundamental physics as well as technology exploitation. The redefinition is not expected to affect any of the existing commercial frequency standard uncertainties such as those of caesium beam clocks or hydrogen masers, because their uncertainties are generally orders of magnitude higher than the expected accuracy of the new definition. Same is true for caesium fountains. The computation and dissemination of UTC will also not change, but UTC will become more stable and accurate based on the improved optical realizations of the SI second. We would like to ask your expert opinion on whether the redefinition may have any impact be it negative or positive on your field of study and operation. The issues we would like you to consider are not just scientific and technological, but also regulatory and legislative. Your answers will be carefully examined and taken into account by CCTF in their analysis of Time and Frequency metrology current and future needs and SI second and UTC evolution. You can find the survey at https://www.surveymonkey.com/r/CCTF_Survey_2020 and in the attached letter from CCTF president Noël Dimarcq you will find additional information on other activities at CCTF for your reference. Best regards, The CCTF Task Force on the redefinition of the second, subgroup A Co-chairs: Marina Gertsvolf (marina.gertsvolf(a)nrc-cnrc.gc.ca<mailto:marina.gertsvolf@nrc-cnrc.gc.ca>) Gaetano Mileti (gaetano.mileti(a)unine.ch<mailto:gaetano.mileti@unine.ch>) Secretary: Frederic Meynadier(frederic.meynadier(a)bipm.org<mailto:frederic.meynadier@bipm.org>)

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[CCTF_survey on Time and Frequency metrology]
by Patrizia TAVELLA Jan. 25, 2021

Jan. 25, 2021

Dear Colleague, in December you should have received the announcement of a CCTF survey (see below) aiming to understand the needs and the opinions of the time and frequency community. Please remind that the deadline for the survey is January 31, 2021. This is an important possibility to contribute to the future way forward on some hot topics. Thanks to those who have already answered. Your contribution is really appreciated. Best wishes for the new year Dear Colleague, the Consultative Committee for Time and Frequency (CCTF) is currently working on very important topics concerning the field of Time & Frequency Metrology and its applications. They are: 1. Updating the Roadmap for the redefinition of the second 2. Leap seconds in UTC - building a consensus for a continuous timescale 3. Promoting the mutual benefit of UTC and GNSS 4. Sharing resources to improve international timekeeping To make sure that the needs and wishes of concerned institutional bodies and stakeholder communities are integrated into the general debate, we have prepared specific questionnaires, that we kindly ask you to answer. Your answers, opinions, and ideas will be carefully examined and taken into account by the CCTF in order to provide future guidelines and recommendations. Please find attached a letter explaining the process. Thanks for the contribution you can give to this survey. Please feel free to forward this email to other colleagues in your field that may give useful feedback, and please apologize for multiples emails you may receive on this topic. with sincere appreciation, on behalf of the CCTF, Noel Dimarcq CCTF President Dr Patrizia Tavella Director of Time Department Bureau International des Poids et Mesures Pavillon de Breteuil 12 bis grande rue 92312 Sèvres Cedex Tel : +33 (1) 45 07 7076 Email patrizia.tavella(a)bipm.org<mailto:patrizia.tavella@bipm.org>

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[tz-announce] 2021a release of tz code and data available
by Paul Eggert Jan. 24, 2021

Jan. 24, 2021

The 2021a release of the tz code and data is available. It reflects the following changes, which were either circulated on the tz mailing list or are relatively minor technical or administrative changes: Changes to future timestamps South Sudan changes from +03 to +02 on 2021-02-01 at 00:00. (Thanks to Steffen Thorsen.) Here are links to the release files: https://www.iana.org/time-zones/repository/releases/tzcode2021a.tar.gz https://www.iana.org/time-zones/repository/releases/tzdata2021a.tar.gz https://www.iana.org/time-zones/repository/releases/tzdb-2021a.tar.lz As usual, links to the latest release files are here: https://www.iana.org/time-zones/repository/tzcode-latest.tar.gz https://www.iana.org/time-zones/repository/tzdata-latest.tar.gz https://www.iana.org/time-zones/repository/tzdb-latest.tar.lz Links are also available via plain HTTP, and via FTP from ftp://ftp.iana.org/tz/releases with the same basenames as above. Each release file has a GPG signature, which can be retrieved by appending ".asc" to the above URLs. Copies of these signatures are appended to this message. This release corresponds to commit 336c8f8262e31116878b079abba80b1626baaa8f dated 2021-01-24 10:54:57 -0800 and tagged '2021a' in the development GitHub repository at <https://github.com/eggert/tz>. Here are the SHA-512 checksums for the release files: bf1d53bcbfecd3b09d57a9e6d3cb49b5dc5f8e1b6674b67e7f974e1a268c2aaf13ca89a7ef12f49d0665aff782bd72685e00c22a41ca88a028da0429f972fd45 tzcode2021a.tar.gz 7cdd762ec90ce12a30fa36b1d66d1ea82d9fa21e514e2b9c7fcbe2541514ee0fadf30843ff352c65512fb270857b51d1517b45e1232b89c6f954ba9ff1833bb3 tzdata2021a.tar.gz 1878ec039db73d3255d808e2b28a5acf2b384d4c5d178aaa2048b5b73cd6b34d03c2ab7282ed615d286b695fa46c628d7e4b6fb6f84bf1905ac8dfbb740769c1 tzdb-2021a.tar.lz Here are the GPG digital signatures for the release files: -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEfjeSqdis99YzvBWI7ZfpDmKqfjQFAmANxdIACgkQ7ZfpDmKq fjRy5g//Y/CPFNFyrlCJSvZT8pP5f+qGfntGfUGEXBJRdFNmGW8KU/wRLHrK+mEP 8VQgPKZqYaKQwJvVTrDycs96Ntm62sKbzb/tSr04JvxYYcJa4ecvMISI8ePI/M9m sKNoKLDuok/Dnl9yntvDWFjLkw43TBMqZRj+oXxMz9Ui8Cap4iZFZfw+tgedwjUk 8mkd45xLQJ5D9k9K6bXvgy0KIFvhN7+Td16do94QHx86gaiSwgzey81rqetzHisb fj329dq2xMa+5bKxS8QDfbL05HOrxQBKmgJQNl2E7MvonBbXAjrd56FQJjGkaViM cTwhQecrElm9bPIzNduV2zy6CyE+5ZlQcYrUJ73g4pH1kZ7H4S5UdIL0O8sdcDOW Gjj0xUMGdwUpI0k2VkKvMjKQ1LzT/vKZy0S4n2LlHTOtIifUA5SigQ1tPmQuWwW+ XfbDb2reeq1mUzphHvwsakKOSPRfwVeszfN4lgOmh3hOpPvEEkzEhQYVOKYwBvEr sK+zl0a+c3ePOMioC9uUF56B38bRgVcTojA/suaoMJEH8IE8wLBT4dSEjofA0wya kKVpvHZiwTj5mM7bMVgq+gtvaQprI52k/X6HWcBD4CcL0dOMQswmz8Sv2LGd7IFK oFm30G2vBVIzprcKdeezYU83EAeUnASbDt5kPm5PCnzELmgRu4E= =pUNC -----END PGP SIGNATURE----- -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEfjeSqdis99YzvBWI7ZfpDmKqfjQFAmANxdIACgkQ7ZfpDmKq fjTnYRAAnozc58/XHxdZ92os3TIzGZHDt4jWZt7zeSlzag7C9r0pvq2u0K0AZVPG yGMUpNlFm2fcbks65En8+wRVZ/5AJeEkUA4V2DDMlf5yDtiXZyt42YTu0UL/saZ3 wHEZIPySeZWKdUILp9BTD9ZDmY2VbIceL1PGMfs00Ti98UgmsNG8yJPMD2E86T3H dcsx7kTYFou9KYuvm3GDlxrQO7X/sTVVEnWJF7Z8rLQz4wjPnYn6Lspoav+N0HNR ycRXSADS3c2kjlaeRjjYVKaekJ3oIXvWgfXcYb1CcB59bACDi4HOMvd8kMU/PV5R p7lkZpSvSNNy/5j5MJDV79YVBwas5++yjv8bQZPkDnS/1YvW9I8ca4YYeTGEA1/G 89sysUlUEYzuojs+oApgqFFAwl+Eo0y5MLyOuRxcXgWw6+eTW6oHHaUXLDFq9jwR d0biMlHIFZNyKHZ72dUbSLo8FalHspHdRYBCppwU8cCprJlPc43zuljru86jRYuW jr228IpKq75ngtXbOHexVrnJejCp/NuV3rcfP3FjC2C3HC2Ao95FO9xT0ZlcTpXq +wu2wZ8csf1RO/hzyOHtcpuFZBRL5a4ZQNvqydFgMgfx2oZcSIAz3GmA8qt5BjHQ C+JwBd00A4JvOigUMvprSSvu3OEOv2kCLgAQSJPOSGWbkrr0s08= =5dc0 -----END PGP SIGNATURE----- -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEfjeSqdis99YzvBWI7ZfpDmKqfjQFAmANxdQACgkQ7ZfpDmKq fjQKOg//RWKxqgAHjfiurbEV8E4KJfA1FCN9lnj8Yd0y5r7QXmABKpJvTa//oqy1 s6OvcAlw9KtBx69F5AR8O3/cJSK8ITKTApoYBDoOhPxBQBYkWAg5tM5Eajv0nOlm HlsnKi0jR/vTyDEhBl4XX/dqzcQF0qb0dmdd+Bm5aB3VjeYC5RlebizT5BHEjTtB 2kw/fkoWYt9r9x+drLwTTDeKB2P7PGZiiOsru5sReWJd5liH/htgC9oC8j4vmbKC BnAFAoRtOYiazAJmyc/da4PJXHEBPnsL9iBxGLR265kkn6rg1v+SJhsBQm5Xj3Ci zwDsX4+93Uk2ezU/Eyk+zvIhKIWWWjcSdWa4zVjLROBvX9jQ1xBSFcTN1mBXccEg pbu9U29qISOY11RqtenC++1KXdNFlLdWiNvuLNNYmSRPOVSyfz+h57wkXqj3zlSS MAH6xGdIGH043pofOgmrVkgyywJ8C195ajmgjQoG5CxCf/o1YgBgoJyd07xPZlEv D94ZShvuXMDHtQ7eJOoFcVTOcIRj5WvEmxxup4eEDmFULOQ2RrVphYTkpVApp5ks kQVPxDkANq7cNwBDokuzV9cDX+ScnSEMs7k79TMB1S2szuM/W8g2ZTN2wwQoZq4T 8QMKHQPMTU72IesC38+bn7V2dHxR14jT+tpjVZc3FsguILd7Ev0= =o/OB -----END PGP SIGNATURE----- PS. If your tzdata parser does not yet support negative DST offsets or times past 24:00, or if it insists on a 'pacificnew' file that is no longer present, this release's data entries can be turned into a rearguard-format tarball that should work even with these older parsers. This is intended to be a temporary transition aid for these parsers. To generate a rearguard-format tarball, obtain the full distribution as described above, and run the command 'make rearguard_tarballs' on a development host. Or you can run 'make rearguard.zi' to generate a single file that can be fed directly to a parser that works like 'zic'.

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[PATCH] Update web links
by Paul Eggert Jan. 24, 2021

Jan. 24, 2021

* tz-link.html: Remove broken links and links to expired drafts. C++20 is now official. Replace CIA time zone map link to a more-general link, as the old link’s replacement has a long cookie-like component and is possibly unstable. --- tz-link.html | 45 ++++++++++++++++----------------------------- 1 file changed, 16 insertions(+), 29 deletions(-) diff --git a/tz-link.html b/tz-link.html index 56ef9e4..abe38d8 100644 --- a/tz-link.html +++ b/tz-link.html @@ -352,12 +352,7 @@ transferring time zone data by reference. <a href="https://devguide.calconnect.org/Time-Zones/TZDS/">TZDIST implementations</a> are available. The <a href="https://www.ietf.org/mailman/listinfo/tzdist-bis">tzdist-bis -mailing list</a> discussed the Internet draft <a -id="TZDIST-Geolocate" -href="https://tools.ietf.org/html/draft-murchison-tzdist-geolocate">TZDIST -Geolocate Extension</a> (now expired), which let a client determine its timezone -from its geographic location using a <a -href="https://tools.ietf.org/html/rfc5870">'geo' URI</a>.</li> +mailing list</a> discusses possible extensions.</li> <li>The <a href="https://tools.ietf.org/html/rfc5545"> Internet Calendaring and Scheduling Core Object Specification (iCalendar)</a> (Internet <abbr>RFC</abbr> 5445) @@ -410,11 +405,11 @@ transition in the <code><abbr>tz</abbr></code> database.</li> <li>The <a href="https://howardhinnant.github.io/date/tz.html">Time Zone Database Parser</a> is a <a href="https://en.wikipedia.org/wiki/C%2B%2B">C++</a> parser and -runtime library with API <a -href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0355r7.html">adopted -into the draft standard</a> for +runtime library with <a +href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0355r7.html">API</a> +adopted by <a href="https://en.wikipedia.org/wiki/C++20">C++20</a>, -the next iteration of the C++ standard. +the current iteration of the C++ standard. It is freely available under the <abbr title="Massachusetts Institute of Technology">MIT</abbr> license.</li> <li><a id="ICU" href="http://site.icu-project.org">International Components for @@ -627,11 +622,6 @@ It is freely available under the <abbr>GPL</abbr>.</li> implementations contain a copy of a 32-bit subset of a recent <code><abbr>tz</abbr></code> database in a Go-specific format.</li> -<li><a -href="http://users.skynet.be/Peter.Verthez/projects/intclock/">International -clock (intclock)</a> is a clock that displays multiple time zones on -<abbr>GNU</abbr>/Linux and similar systems. It is freely available -under the <abbr>GPL</abbr>.</li> <li>Microsoft Windows 8.1 and later has <code><abbr>tz</abbr></code> data and <abbr>CLDR</abbr> data (mentioned <a href="#CLDR">below</a>) used by the @@ -677,10 +667,7 @@ licenses</a> to <code><abbr>tz</abbr></code> contributors.</li> is Astrodienst's Web version of Shanks and Pottenger's out-of-print time zone history atlases <a href="https://www.worldcat.org/oclc/468828649">for the US</a> and -<a href="https://www.worldcat.org/oclc/76950459">for the world</a>, -now published in <a -href="https://astrocom.com/astrology-products/software/acs-atlas-software">software</a> -form by <a href="https://astrocom.com">ACS-Starcrafts</a>. +<a href="https://www.worldcat.org/oclc/76950459">for the world</a>. Although these extensive atlases <a href="https://astrologynewsservice.com/opinion/how-astrologers-contributed-to-the…">were sources for much of the older <code><abbr>tz</abbr></code> data</a>, @@ -704,11 +691,13 @@ gives current time zone rules for airports served by commercial aviation.</li> <section> <h2 id="maps">Maps</h2> <ul> -<li>The <a href="https://www.cia.gov/index.html">United States Central -Intelligence Agency (<abbr -title="Central Intelligence Agency">CIA</abbr>)</a> publishes a <a -href="https://www.cia.gov/library/publications/the-world-factbook/graphics/ref_ma…">time -zone map</a>; the +<li>The <a +href="https://www.cia.gov/the-world-factbook/maps/world-regional/">World +and Regional Maps section</a> of <em>The World Factbook</em>, published by the +<a href="https://www.cia.gov">US Central Intelligence +Agency (<abbr +title="Central Intelligence Agency">CIA</abbr>)</a>, contains a time +zone map; the <a href="https://legacy.lib.utexas.edu/maps/world.html">Perry–Castañeda Library Map Collection</a> @@ -734,7 +723,9 @@ where the two differ greatly. It's a bit out of date, unfortunately.</li> <section> <h2 id="boundaries">Time zone boundaries</h2> <p>Geographical boundaries between timezones are available -from several <a href="https://en.wikipedia.org/wiki/Geolocation">geolocation</a> +from several <a +href="https://en.wikipedia.org/wiki/Internet_geolocation">Internet +geolocation</a> services and other sources.</p> <ul> <li><a href="https://github.com/evansiroky/timezone-boundary-builder">Timezone @@ -883,10 +874,6 @@ of Legal Time in Germany</a>.</dd> <dd>The Interior Ministry periodically issues <a href="ftp://ftp.cs.huji.ac.il/pub/tz/announcements" hreflang="he">announcements (in Hebrew)</a>.</dd> -<dt>Italy</dt> -<dd>The National Institute of Metrological Research publishes a -<a href="http://oldsite.inrim.it/res/tf/ora_legale_i.shtml" hreflang="it">table -of civil time (in Italian)</a>.</dd> <dt>Malaysia</dt> <dd>See Singapore <a href="#Singapore">below</a>.</dd> <dt>Mexico</dt> -- 2.27.0

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South Sudan to change time zone?
by Steffen Thorsen Jan. 20, 2021

Jan. 20, 2021

Quite a few sources, but they seem mostly to be syndicated from the same story tell that: "South Sudan will change its time zone by setting the clock back 1 hour on February 1, 2021, the government spokesperson has said. According to the minister of information, Michael Makuei Lueth, South Sudan will change its offset from UTC+3 to UTC+2." from https://eyeradio.org/south-sudan-adopts-new-time-zone-makuei/ and a bit different here: https://radiotamazuj.org/en/news/article/south-sudan-to-change-time-zone-ne… Best regards, Steffen Thorsen - timeanddate.com

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Kyiv NOT Kiev
by Vyacheslav Lukin Jan. 18, 2021

Jan. 18, 2021

Hello, My name is Viacheslav Lukin and I live in Kyiv, Ukraine. Could you please change incorrect spelling Kiev in database to correct Kyiv? Campaing #KyivNotKiev: https://en.wikipedia.org/wiki/KyivNotKiev Wikipedia and Google use the spelling Kyiv: https://en.wikipedia.org/wiki/Kyiv https://www.google.com/maps/place/Kyiv In Ukraine use the spelling Kyiv: https://static.ukrinform.com/photos/2015_10/thumb_files/630_360_1443988512-… https://static.ukrinform.com/photos/2019_02/thumb_files/630_360_1550082358-… https://static.dw.com/image/49169749_303.jpg Ukrainian companies use the spelling Kyiv: https://kyivstar.ua/ https://www.kyivpost.com/

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Rename timezone
by Вітя kor0p Jan. 18, 2021

Jan. 18, 2021

Hello, I'm from Ukraine, and I want to change the name of Europe/Kiev timezone to Europe/Kyiv, because it's the right translation of the capital of Ukraine. Some countries, media, and organizations start using the correct name. #KyivNotKiev. The wiki article about this: https://en.wikipedia.org/wiki/Kyiv With hope to changes, Victor

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Negative leap seconds in mainstream media
by Arthur David Olson Jan. 12, 2021

Jan. 12, 2021

"Why Scientists Want to Shorten the Minute to 59 Seconds" https://www.popularmechanics.com/science/a35165130/leap-second-shorten-minu… (As noted on Twitter by Molly Conger, @socialistdogmom.) @dashdashado

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No leap second on 2021-06-30
by Tim Parenti Jan. 9, 2021

Jan. 9, 2021

Per IERS, Bulletin C 61 (2021-01-07) https://hpiers.obspm.fr/iers/bul/bulc/bulletinc.61 …and forwarded below. A patch updating leap-seconds.list from NIST is attached, and is installed in the development repository. -- Tim Parenti ---------- Forwarded message --------- From: IERS EOP Product Center <iers.eoppc(a)obspm.fr> Date: Thu, 7 Jan 2021 at 08:05 Subject: Bulletin C number 61 To: <bulc.iers(a)obspm.fr> INTERNATIONAL EARTH ROTATION AND REFERENCE SYSTEMS SERVICE (IERS) SERVICE INTERNATIONAL DE LA ROTATION TERRESTRE ET DES SYSTEMES DE REFERENCE SERVICE DE LA ROTATION TERRESTRE DE L'IERS OBSERVATOIRE DE PARIS 61, Av. de l'Observatoire 75014 PARIS (France) Tel. : +33 1 40 51 23 35 e-mail : services.iers(a)obspm.fr http://hpiers.obspm.fr/eop-pc Paris, 07 January 2021 Bulletin C 61 To authorities responsible for the measurement and distribution of time INFORMATION ON UTC - TAI NO leap second will be introduced at the end of June 2021. The difference between Coordinated Universal Time UTC and the International Atomic Time TAI is : from 2017 January 1, 0h UTC, until further notice : UTC-TAI = -37 s Leap seconds can be introduced in UTC at the end of the months of December or June, depending on the evolution of UT1-TAI. Bulletin C is mailed every six months, either to announce a time step in UTC, or to confirm that there will be no time step at the next possible date. Christian BIZOUARD Director Earth Orientation Center of IERS Observatoire de Paris, France

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Europe/Kiev to be renamed to Europe/Kyiv
by Андрій Лавріненко Jan. 8, 2021

Jan. 8, 2021

Good afternoon! I'd like to report that the spelling of this Ukrainian city name has been changed from Kiev to *Kyiv*, as reflected by Google Maps <https://www.google.com/maps/place/%D0%9A%D0%B8%D1%97%D0%B2,+%D0%A3%D0%BA%D1…>, Wikipedia <https://en.wikipedia.org/wiki/Kyiv>, the UN <https://www.un.org/Depts/Cartographic/map/profile/ukraine.pdf>. Hope that will be useful to inform the tz name update. -- Best regards, Andrii Lavrinenko

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