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Any objections? --[[User:John Maynard Friedman|John Maynard Friedman]] ([[User talk:John Maynard Friedman|talk]]) 21:57, 1 November 2019 (UTC)
:I read the reference at [2] and don't see any mention of climatic events affecting Earth's rotation. Are you sure they have a measurable contribution? [[Special:Contributions/31.168.44.122|31.168.44.122]] ([[User talk:31.168.44.122|talk]]) 08:39, 22 December 2024 (UTC)
::The debate about the lead finished some time ago but, since you raised the point, here is a recent reference: [https://www.nhm.ac.uk/discover/news/2024/march/climate-change-causing-days-get-longer-slowing-down-earth.html Climate change is causing days to get longer by slowing down the Earth] (Natural History Museum). It is the effect seen when an ice-skater spins on the spot with arms up v. outstretched.--[[User:JMF|𝕁𝕄𝔽]] ([[User talk:JMF|talk]]) 13:01, 22 December 2024 (UTC)
:::"It's an ill wind" etc. The article needed to be updated with that info, which I have now done. So thank you for raising it. --[[User:JMF|𝕁𝕄𝔽]] ([[User talk:JMF|talk]]) 16:02, 22 December 2024 (UTC)
{{reflist talk}}
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:::::Serious time-stamp critical applications should be written to work in the presence of positive and negative leap seconds. In today's world, everything is software, and the software can be written correctly. It isn't actually hard to do, it just takes the will to do it. [[User:John Sauter|John Sauter]] ([[User talk:John Sauter|talk]]) 02:49, 18 September 2021 (UTC)
::::::Mr. John Sauter, please let me tell you that since negative leap second has never been introduced, it is terra incognita for the engineers, <ins>as in programming "undefined behavior" and "unexpected results" should always be expected</ins>. That's the problem. [[User:Georges T.|Georges T.]] ([[User talk:Georges T.|talk]]) 12:21, 18 September 2021 (UTC) 13:53, 21 September 2021 (UTC)
:::::According to [https://www.ucolick.org/~sla/leapsecs/ "Future of Leap Seconds"] website, there are potential legal issues that would occur in countries like USA, Great Britain, and Canada, that still regard GMT (i.e. UT1) as legal time. For example, an accident recorded on camera, occurring seconds from midnight, may or may not be subject to insurance payout if insurance expires on that midnight. So I would say there are definitely potential issues, and they are not necessarily related to software only. [[User:Morycm|Morycm]] ([[User talk:Morycm|talk]]) 00:22, 1 March 2024 (UTC)
Mr. John Sauter, please let me express you my many thanks for you commented my proposal. Regarding situation in 2000 I post this [https://hpiers.obspm.fr/eop-pc/products/combined/C04plot.php?date=2&dimx=1200&dimy=800&graphe=3&year1=1998&month1=1&day1=1&year2=2006&month2=12&day2=31&langue=1&SUBMIT=Submit+request plot]. It is clear that there was not any increase similar to that since June 2021. By the way, let me suggest you and every interested [https://hpiers.obspm.fr/eop-pc/index.php?index=C04&lang=en this] IERS/EOC page for retrieving data and plots. My way for predictions under aforementioned condition is that in 2 months (June 17 to August 17) increase was 44 msec that is 22 per month. With regards and friendship, Georges Theodosiou, The Straw Man [[User:Georges T.|Georges T.]] ([[User talk:Georges T.|talk]]) 14:52, 17 September 2021 (UTC)
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Ladies, Gentlemen, please let me report you (IERS snob my messages) something strange. Despite their name (International EARTH ROTATION Service), they do <del>not</del> (<ins>actually they do as Δω<sub>3</sub>, I apologize</ins>) publish in their proper [https://hpiers.obspm.fr/eop-pc/index.php?index=C04&lang=en page] data and plots for EARTH ROTATION speed (omega). Though omega is UT1's independent variable according to Newcomb's formula (omega replaces sidereal time), UT1-UTC depends on two speeds: omega and cesium atom's oscillation. <ins>It follows, monitoring UT1-UTC (or UT1-TAI) we do not monitor omega.</ins> With regards and friendship, Georges Theodosiou, The Straw Man [[User:Georges T.|Georges T.]] ([[User talk:Georges T.|talk]]) 07:25, 29 September 2021 (UTC) 09:50, 27 April 2022 (UTC)
=== Keeping an eye on Earth's Omega ===
Ladies Gentlemen, please let me tell you that in IERS/EOC data, [https://hpiers.obspm.fr/eop-pc/products/combined/C04plot.php?date=2&dimx=1200&dimy=900&tver=1&graphe=55&year1=2020&month1=1&day1=1&year2=2031&month2=12&day2=31&langue=1&SUBMIT=Submit+request Δomega] and [https://hpiers.obspm.fr/eop-pc/products/combined/C04plot.php?date=2&dimx=1200&dimy=900&tver=1&graphe=5&year1=2020&month1=1&day1=1&year2=2031&month2=12&day2=31&langue=1&SUBMIT=Submit+request ΔLOD] (from [https://hpiers.obspm.fr/eop-pc/index.php?index=C04&lang=en this] page) supported by Vondrak filter's [https://hpiers.obspm.fr/eop-pc/index.php output] one can see that in late 2022 earth is decelerating making positive leap second more probable than negative. Indeed only God knows how long it will last. With regards and friendship Georges Theodosiou. [[User:Georges T.|Georges T.]] ([[User talk:Georges T.|talk]]) 16:48, 15 December 2022 (UTC)▼
▲Ladies Gentlemen, please let me tell you that in IERS/EOC <del>data</del> <ins>plots</ins> ([[User:Georges T.|Georges T.]] ([[User talk:Georges T.|talk]]) 10:49, 2 February 2023 (UTC)), [https://hpiers.obspm.fr/eop-pc/products/combined/
:The Earth's rotation rate is seasonal. It is clear from the charts you referenced that the Earth spins faster during Northern Hemisphere summer.s. To get a useful prediction of the future rate of rotation of the Earth you need to look at a year's worth of data.
:The IERS has predicted that the Earth's rate of rotation will continue to be slower than one per 86,400 seconds over the next year. My guess, based on projecting the IERS prediction further into the future than one year, is that we will have a negative leap second somewhere around the end of this decade. [[User:John Sauter|John Sauter]] ([[User talk:John Sauter|talk]]) 15:02, 17 December 2022 (UTC)
::Dear Sauter, please accept my thanks for you answered my message. In Vondrak filter's output it's clear that earth is decelerating in second semester 2022. It is supported by Δomega and ΔLOD graphs. In Δomega, zigzag in October-November is clear lower than in same months last year. In ΔLOD is clear higher. Both mean deceleration independent of tidal and seasonal variations, a random, unexpected, deceleration. With regards and friendship, G. Theodosiou The Straw Man. [[User:Georges T.|Georges T.]] ([[User talk:Georges T.|talk]]) 10:07, 20 December 2022 (UTC)
:::Although this trend is clear to you, it is not clear to me, or to the IERS, which continues to predict that over the next year, at least, the length of the day will continue to be less than 86,400 seconds. If you have a mathematical basis for your prediction that the length of the day will increase to over 86,400 seconds enough to cause a positive leap second, perhaps you could present it here. We can then compare your predictions of the length of day with the measured values reported to the IERS. If your predictions turn out to be more accurate than the IERS predictions you will gain credibility. [[User:John Sauter|John Sauter]] ([[User talk:John Sauter|talk]]) 16:34, 20 December 2022 (UTC)
::::Mr. Sauter, please let me tell you that credibility's worth is 0 and < 0. With regards and friendship, G. Theodosiou, The Straw Man, [[User:Georges T.|Georges T.]] ([[User talk:Georges T.|talk]]) 07:08, 28 March 2023 (UTC)
:Mr. Sauter, please let me tell you that I predict all <del>of the remaining</del> leap seconds <ins>before 2037</ins> will be positive, based on the periodic metonic fluctuation of [https://hpiers.obspm.fr/eop-pc/products/combined/C04plottest.php?date=2&dimx=1200&dimy=900&graphe=55&year1=1962&month1=1&day1=1&year2=2031&month2=12&day2=31&langue=1&SUBMIT=Submit+request ΔΩ]. With regards and friendship, G. Theodosiou, The Straw Man [[User:Georges T.|Georges T.]] ([[User talk:Georges T.|talk]]) 12:10 5 April 2024 (UTC), [[User:Georges T.|Georges T.]] ([[User talk:Georges T.|talk]]) 13:45, 8 April 2024 (UTC).
::Thank you for your definite and clear prediction. It will be interesting to see if you are correct. [[User:John Sauter|John Sauter]] ([[User talk:John Sauter|talk]]) 16:09, 7 April 2024 (UTC)
Ladies, Gentlemen, please let me report you an important error in [https://hpiers.obspm.fr/eop-pc/index.php?index=C04&lang=en IERS]'s UT1-UTC data [https://hpiers.obspm.fr/eop-pc/products/combined/C04plottest.php?date=2&dimx=1200&dimy=900&tver=1&graphe=3&year1=2021&month1=7&day1=1&year2=2031&month2=12&day2=31&langue=1&SUBMIT=Submit+request averaged] for tidal variations ("Remove tidal variations" checked), in respect to [https://hpiers.obspm.fr/eop-pc/products/combined/C04plottest.php?date=2&dimx=1200&dimy=900&graphe=3&year1=2021&month1=7&day1=1&year2=2031&month2=12&day2=31&langue=1&SUBMIT=Submit+request original]. <ins> Compare ΔLOD data, [https://hpiers.obspm.fr/eop-pc/products/combined/C04plottest.php?date=2&dimx=1200&dimy=900&graphe=5&year1=2021&month1=7&day1=1&year2=2031&month2=12&day2=31&langue=1&SUBMIT=Submit+request original] and [https://hpiers.obspm.fr/eop-pc/products/combined/C04plottest.php?date=2&dimx=1200&dimy=900&tver=1&graphe=5&year1=2021&month1=7&day1=1&year2=2031&month2=12&day2=31&langue=1&SUBMIT=Submit+request averaged]. Latter are mean values of the former. [[User:Georges T.|Georges T.]] ([[User talk:Georges T.|talk]]) 12:34, 16 August 2023 (UTC)</ins>. With regards and friendship, G. Theodosiou, The Straw Man [[User:Georges T.|Georges T.]] ([[User talk:Georges T.|talk]]) 07:49, 2 August 2023 (UTC)
Ladies, Gentlemen, please let me tell you interesting facts regarding IERS's monitoring of Earth's omega. At IERS/EOC's [https://hpiers.obspm.fr/eop-pc/index.php front page] the plot depicts LOD as having equal value in the middle of the year and a year earlier. In the [https://hpiers.obspm.fr/eop-pc/products/combined/C04plottest.php?date=2&dimx=1200&dimy=900&tver=1&graphe=5&year1=2021&month1=8&day1=1&year2=2031&month2=12&day2=31&langue=1&SUBMIT=Submit+request IERS/EOC] and [https://maia.usno.navy.mil/information/plots IERS/RS-PC] (last plot) charts, the zigzags in the middle of the 2023 and 2022 should be at the same height if it were true, but they are not. On the other hand, if you click on their Vondrak filter chart, a back page appears. It is slightly different from the front one and might be accurate. The curve at midyear is still higher than the curve at midyear 2022. By the way, I should mention that I used a paraphrasing tool this time. Please offer your opinion. With regards and friendship, Georges Theodosiou, The Straw Man, [[User:Georges T.|Georges T.]] ([[User talk:Georges T.|talk]]) 14:30, 1 September 2023 (UTC). <ins>Now, the front and back charts on the IERS/EOC website are identical. Those are IERS/EOC. [[User:Georges T.|Georges T.]] ([[User talk:Georges T.|talk]]) 14:39, 1 September 2023 (UTC)</ins>
Ladies, Gentlemen, please permit me to point out that there are clearly three metonic cycles (1964–1984, 1984–2004, 2004–2024 ) in [https://hpiers.obspm.fr/eop-pc/products/combined/C04plottest.php?date=2&dimx=1200&dimy=900&graphe=5&year1=1962&month1=1&day1=1&year2=2031&month2=12&day2=31&langue=1&SUBMIT=Submit+request this] and [https://hpiers.obspm.fr/eop-pc/products/combined/C04plottest.php?date=2&dimx=1200&dimy=900&graphe=55&year1=1962&month1=1&day1=1&year2=2031&month2=12&day2=31&langue=1&SUBMIT=Submit+request this] plots. The fact that there is continual acceleration is clearly evident. With regards and friendship, Georges Theodosiou, the Straw Man, [[User:Georges T.|Georges T.]] ([[User talk:Georges T.|talk]]) 13:49, 4 April 2024 (UTC)
:The continual acceleration is not evident to me. It seems more like randomness. Perhaps you can explain so I can understand. [[User:John Sauter|John Sauter]] ([[User talk:John Sauter|talk]]) 11:54, 7 April 2024 (UTC)
:: Mr. Sauter, please let me express my thanks for you replied my message and more for you stated your view. I agree, it is a long-term random acceleration. With regards and friendship, G. Theodosiou, The Straw Man, [[User:Georges T.|Georges T.]] ([[User talk:Georges T.|talk]]) 13:51, 8 April 2024 (UTC)
Let me explain my prognosis, Ladies and Gentlemen, for leap seconds up to 2037. I notice short-term accelerations and decelerations in the earth's Δomega signal, irregularities according to Dr. Bizourd IERS/EOC Directior, randomness according to Dr. Sauter, and noise according to DSP jargon. They are unable to undermine my forecast. In fact, it will be discouraged if a new long-term acceleration appears. With regards and friendship, G. Theodosiou, The Straw Man, [[User:Georges T.|Georges T.]] ([[User talk:Georges T.|talk]]) 09:07, 11 May 2024 (UTC)
Ladies, Gentlemen, permit me to briefly describe my current observations regarding Earth's omega. 1) In [https://hpiers.obspm.fr/eop-pc/products/combined/C04plottest.php?date=2&dimx=1200&dimy=900&graphe=55&year1=1962&month1=1&day1=1&year2=2031&month2=12&day2=31&langue=1&SUBMIT=Submit+request this] plot I observe 3 (1963-2023) metonic periods. 2) The increasing slope of Omega's digital signal indicates long-term acceleration. 3) This acceleration is weaker than that of decelerating metonic semi-periods. 4) In the time being decelerating semi-period is active 5) For the most part, it turns negative <ins>causing positive leap seconds (10 January 2025) 6) [https://www.google.com/search?client=firefox-b-d&q=The+year+2035+for+eliminating+leap+seconds+was+chosen+considering+Russia%27s+request+to+extend+the+timeline+to+2040%2C+ The year 2035 for eliminating leap seconds was chosen considering Russia's request to extend the timeline to 2040]. The next peak of the metonic period will occur in 2040. Russia's request will undoubtedly require a negative leap second before the end of the next decade if the ITU grants it (17 January 2025)</ins>. With regards and friendship, Georges Theodosiou, the Straw Man, [[User:Georges T.|Georges T.]] ([[User talk:Georges T.|talk]]) 16:05, 9 January 2025 (UTC)
===A useful page of links to the future of leap seconds===
*{{cite web |first=Steve |last=Allen | publisher = University of California Observatories, Lick | title= UTC might be redefined without Leap Seconds |url=https://www.ucolick.org/~sla/leapsecs/}}
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:::Yet another possibility is that it will not be possible to get all the details worked out by 2035, so leap seconds will continue until they are. [[User:John Sauter|John Sauter]] ([[User talk:John Sauter|talk]]) 15:39, 19 November 2022 (UTC)
::::It seems that ''Nature'' [https://www.nature.com/articles/d41586-022-03783-5 is not convinced] that the decision is final either. --[[User:John Maynard Friedman|𝕁𝕄𝔽]] ([[User talk:John Maynard Friedman|talk]]) 11:14, 21 November 2022 (UTC)
== Slower by a negative amount? ==
In the History section, shortly after "rubber second": The phrase "slower than the rate of atomic time by −150 parts per 10 (raised to the tenth)" is confusing. Is that dash a "minus sign/negative sign"?
If so: Doesn't ''slower by a negative amount'' mean ''faster''? If "slower" is kept, I suggest removing the negative signs from the various phrases in this section. [[User:David10244|David10244]] ([[User talk:David10244|talk]]) 05:32, 24 January 2023 (UTC)
:I have changed "slowed" to "offset", using words from the source, to make the meaning clearer. [[User:John Sauter|John Sauter]] ([[User talk:John Sauter|talk]]) 06:25, 24 January 2023 (UTC)
::That sounds better, thanks. [[User:David10244|David10244]] ([[User talk:David10244|talk]]) 05:05, 25 January 2023 (UTC)
== Length of day ==
In the Process section, in the phrase "in 1972 the average length of day was approximately 86400.003 seconds and in 2016 it was approximately 86400.001 seconds, indicating an overall increase in Earth's rotation rate over that time period".
It seems like there's a decrease, not an increase, in the rotation rate, since there's a decrease in the "length of day"... if the length of a (rotational) day is measured in "atomic seconds". But I could be reading this wrong -- not sure. [[User:David10244|David10244]] ([[User talk:David10244|talk]]) 05:44, 24 January 2023 (UTC)
:I believe you are reading this wrong. Consider a simpler example: a ball spins at a rate of one rotation every 2 seconds. In order to make the ball spin at a rate of one rotation every second (decreasing the rotation time) you must increase the rotation rate. [[User:John Sauter|John Sauter]] ([[User talk:John Sauter|talk]]) 06:29, 24 January 2023 (UTC)
::Ah, yes, that makes sense. I was backwards on this one. [[User:David10244|David10244]] ([[User talk:David10244|talk]]) 05:06, 25 January 2023 (UTC)
==Article date format==
I notice the date format in the article is inconsistent, especially in the references. [https://en.wikipedia.org/w/index.php?title=Leap_second&diff=next&oldid=331995180 I found the first edit that introduced dates that contained both the day and the month]. It used the dmy format so I have put the {{tl|use dmy dates}} near the top of the article. I will look for inconsistent dates and fix them. [[User:Jc3s5h|Jc3s5h]] ([[User talk:Jc3s5h|talk]]) 16:11, 13 July 2023 (UTC)
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