Talk:Accumulated cyclone energy/Archive 2

Archive 1

Archive 2

Atlantic ACE discrepancy

I’ve noticed that recently the operational ACE for the Atlantic is behind most other estimates and that seems to be because we calculate it by the 6-h operational advisories rather then the operational BT compared to some of the other basins. Plus, the BT points are sometimes revised to correct an intensity whereas the operationals are just non-changing. Is it possible we could switch to this method? I wanna know what y’all think. --MarioProtIV (^talk/_contribs) 20:17, 2 September 2020 (UTC)

We switch to Best Track once the reports are released, for instance at the NHC website. I am not aware of any such reports being completed yet for 2020, or if any Best Track data is available prior to the release of these reports. --Spiffy sperry (talk) 20:43, 2 September 2020 (UTC)

Personally when I looked at Ryan Maue's running totals just now, I noticed that we are about 5 points below his running total, which makes you wonder if our totals are correct. Also @Spiffy sperry: I suspect that @MarioProtIV: is talking about the RBT located here and advertised in every TCR.Jason Rees (talk) 22:56, 2 September 2020 (UTC)

I think you have a point because sometimes the BT can be modified to extend back genesis by 6-12h during the storm (in Nana’s case) or an update or special advisory that ups the intensity after an operational advisory has already been put out (which then is reflected in the BT). I think if we were to switch to operational BT (not final BT) we’ll have the more accurate totals. --MarioProtIV (^talk/_contribs) 23:57, 2 September 2020 (UTC)

Bumping this and pinging @Supportstorm: and @Jasper Deng: (some of the experts in this project) to see what their inputs are. Should note that Ryan’s stats has this message with it: “Preliminary values from real-time ATCF advisories and will become final when best-tracks are available from JTWC and NHC after post-season analysis Small differences have been found in previous years between real-time and best-track ACE.” Makes you wonder about if we really should use operational BT (due to the pros I mentioned above) rather the advisories as we end up a few points lower then most other estimates. --MarioProtIV (^talk/_contribs) 19:38, 7 September 2020 (UTC)

The ATCF has no true official standing; their use for track maps is for convenience purposes only. We shouldn't use it for ACE.--Jasper Deng (talk) 20:25, 7 September 2020 (UTC)

True, but the actual best track file is subject to revisions even during the storm, and sometimes is used to extend back genesis or raise intensity at some point. That is what I’m suggesting, not the ATCF which is just a pre-advisory thing and not really counted toward. --MarioProtIV (^talk/_contribs) 20:37, 7 September 2020 (UTC)

@MarioProtIV: The question has to be asked why we even be calculating the ACE ourselves when there are significant differences in how its worked out? After all, the IMD work it out for all cyclonic disturbances, while Ryan Maue does not include subtropical storms and NOAA does it for subtropical, tropical storms and hurricanes.Jason Rees (talk) 21:05, 7 September 2020 (UTC)

The notion that the BT files in ATCF are not official isn't correct. The ATCF best track files are created by the NHC/JTWC and as Mario has been alluding to have the most up to date data once the storm is finished. In my opinion the Running BT is the better source for calculating ACE operationally if we continue to calculate it ourselves. Supportstorm (talk) 22:05, 7 September 2020 (UTC)

@Supportstorm: No, the NHC has made clear several times that advisories supersede the ATCF best track. I don't think it's meant for public consumption, in fact.--Jasper Deng (talk) 03:35, 8 September 2020 (UTC)

The running best tracks are similar to the finished BT data, which I think would be beneficial to operational ACE calculations. Did not say BT supersedes advisories, but if we are wondering why ACE is behind other sources this is why. The running BT data is on public facing FTP sites. It is also available on the main NHC website, so it is definitely meant for public use. Supportstorm (talk) 04:31, 8 September 2020 (UTC)

Even though they are on a public-facing FTP website, they still aren't really meant to be the public word of the NHC. One such situation was Hurricane Andres: they entered 100 knots but then went 95 in the advisory. The 100 knots did not count for major hurricane status. It was not until the next advisory, after Andres really rapidly intensified in earnest, that they upgraded it to a major hurricane.--Jasper Deng (talk) 19:10, 8 September 2020 (UTC)

@Jasper Deng: Thats one instance but then when you look at say CSU (one of the most recognized and respected forecasting agencies, they have 99 ACE compared to 95 here. The message at the bottom reads “ Real-time statistics calculated from operational best tracks of NHC, CPHC and JTWC.” It really shows how whether or not we are using operational, when we have stats behind the leading experts of hurricane forecasting that really says something about how we’re calculating. In my opinion during the season we just follow the experts (and then calculate our own after TCRs come out) rather then trying to calculate our own because we end up with a bunch of inconsistencies. --MarioProtIV (^talk/_contribs) 15:03, 21 September 2020 (UTC)

@MarioProtIV: They don't update for post-analysis, thus they do not do it correctly. Case closed.--Jasper Deng (talk) 17:32, 21 September 2020 (UTC)

Seasons table: proposal for slightly more user-friendly arrangement and corrections

[Copied from original place on Talk Page for List of Atlantic hurricane records, where I inadvertently started it. That probably also explains a question or two about where to find what I referred to.]Redav (talk) 11:06, 20 October 2020 (UTC)

While I appreciate the sortable table of seasonal aggregates of ACE, TS, HU, and MH in the section "Color–coded historical ACE in recorded Atlantic hurricane history" a lot, I would prefer to have the definitions in the grey fields correspond to the columns.

As things stand now, we have:

• on the one hand: category - ACE - percentage of median - TS - HU - MH for the definitions;
• on the other hand: season - ACE - TS - HU - MH - classification (= category)" for the seasons.

Also the ACE limits 66 and 111 mentioned for the classification are not equal to 66% and 111% of the 1981-2010 median, according to https://www.cpc.ncep.noaa.gov/products/outlooks/Background.html. There it is stated that the median value is 92.4 and that the ACE limits for a normal season are at 71.4% and at 120% of the median value respectively.

I think I could change the arrangement to "percentage of median - ACE - TS - HU - MH - classification" for the definitions and "season - ACE - TS - HU - MH - classification" for the seasons. In that way like information corresponds to like column where applicable. And I would change the percentage values to the ones reported in the source mentioned above.

Any motivated objections?Redav (talk) 15:50, 19 October 2020 (UTC)

Which section are you talking about again? "Seasonal records"? - Knowledgekid87 (talk) 17:22, 19 October 2020 (UTC)

@Knowledgekid87 OK, it is a subsection. There is exactly one subsection titled "Color–coded historical ACE in recorded Atlantic hurricane history" and exactly one table in it. Cheers!Redav (talk) 20:19, 19 October 2020 (UTC)

Personally I feel that we need to look again at the Accumulated cyclone energy article, since as the article says and shows: ACE is a metric that is used by a number of people for various purposes. It is also noteworthy that the definition of ACE is not uniform, with some adding in tropical depressions while others dont.Jason Rees (talk) 21:15, 19 October 2020 (UTC)

I agree with you if that is the root cause of the problem. - Knowledgekid87 (talk) 21:52, 19 October 2020 (UTC)

@Jason Rees, @Knowledgekid87: I do not specialize in ACE calculation, even if I understand it is a very, very rough estimate in that it does not (directly) account for the velocity field, the density field, and the volume of a cyclone where all this kinetic energy rages. Unfortunately, I do not have the appropriate data at my disposal to make a proper approximation of an integral over space and time of density times velocity squared divided by two.

However, that is beside the point I made, which is simply about the presentation in the table that confused me, with different kinds of data and headings in the same column. I can read no objection to me making the proposed changes. If I take care of that now, the metric can be discussed later (or, if I work slowly enough ;-), in parallel).Redav (talk) 23:32, 19 October 2020 (UTC)

I see the second table is now gone. I note the median is not provided despite the table going on about the percentage of median. Only the average is shown on that table. Something is not consistent here.--CyclonicallyDeranged (talk) 05:09, 21 October 2020 (UTC)

Since then I've added the median value to the article.--CyclonicallyDeranged (talk) 05:33, 21 October 2020 (UTC)

What happened to all the ACE data?

This page used to have a useful list of ACE data by year - where did all of the information go? It was a helpful reference for comparing activity across years. CounterintuitiveCyborg (talk) 16:13, 4 September 2020 (UTC)

This page is in the middle of a clean up in order to recognise that the index is used around the world and not just in the Atlantic and Eastern Pacific basins. The data that you are looking for was merged with Atlantic hurricane season and Pacific hurricane, where the data is better placed since ACE is just one metric used to assess seasons.Jason Rees (talk) 16:25, 4 September 2020 (UTC)

Jason Rees has decided that it would be better to remove all that information (by consensus of people with username "Jason Rees") and while moving it, destroy its usefulness by removing it from one sortable table.--Prosfilaes (talk) 06:49, 6 September 2020 (UTC)

Uselles change, confusing me, you just made me mad cause this page was the easiest and most readable way of reading Acumulated Cyclone Energ. Uselles. Change. Andreiii3213 (talk) 16:49, 7 september 2020 (UTC+2 [Polish summer time)

@Andreiii3213: I am sorry that it makes you mad that we have had to remove the list of Atlantic ACE, but it makes me mad to see such a big list of the ACE for the Atlantic. Especially when the list is unsourced, no consensus as to how it should be calculated and is used around the world by more than just NOAA. Jason Rees (talk) 17:22, 7 September 2020 (UTC)

This page is supposed to be an overview of ACE in a global stance and should not focus on specifics regarding each basin. There needs to be a point at where ACE is cut off here. It should only display the top years of each basin. The ACE for the past hundred years needs to be listed in each basin's overview page, not here. Noah^Talk 22:17, 7 September 2020 (UTC)

@Hurricane Noah: And where exactly is the top-list in the Atlantic basin's overview page? Yours, Ciciban (talk) 11:57, 20 September 2020 (UTC)

I would like to make a new section with the WPAC typhoon ACE data, but I’m lacking ACE calculations. For example, it says on the 2004 page that the ACE was 480, but where do you guys get the seasonal ACE total? DavidTheMeteorologist^Talk 12:29, 9 September, 2020 (EDT)

The problem with the ACE Index for the WPAC would that we have no evidence that the JMA has defined the ACE or uses it, which means that its OR imo. However, putting that to one side I wonder how valid that ACE figure in 2004 WPAC is - especially when you notice that the source was published in January 2005 before the JTWC publically released their BT.Jason Rees (talk) 18:42, 9 September 2020 (UTC)

We should not have any ACE information on the western Pacific, but you do not have consensus to outright remove all the ACE tables given the expressed opposition above, and by me below.--Jasper Deng (talk) 22:47, 19 September 2020 (UTC)

You need to cite what "extremely inactive season" is and where it is cited. 216.15.124.9 (talk) 18:04, 13 November 2020 (UTC)

WPAC / Southern Hemisphere totals

http://tropical.atmos.colostate.edu/Realtime/index.php have the ACE totals for two basins but the data is deleted at the end of every season. Thingofme (talk) 16:29, 19 February 2023 (UTC)

Yeah the other problem with using CSU's totals is that they are based on the JTWC's intensity estimates rather than the relevant RSMC/TCWC.Jason Rees (talk) 16:55, 19 February 2023 (UTC)

There are some problems with this, as ACE counts outside of EPAC/NATL are not well documented. Thingofme (talk) 14:07, 27 February 2023 (UTC)

Ioke record

I read many sources articles written that Ioke's record is 85~85.3, why is it only 82 here. Bóng Ma ^{- Talk} 21:49, 10 March 2023 (UTC)

It probably comes down to how you handle the JMAs winds for Ioke.Jason Rees (talk) 22:28, 10 March 2023 (UTC)

yep, and now, Freddy has reached 82.2 ACE points, has this record been surpassed or not? Vệ Thần ^{- Talk} 21:53, 11 March 2023 (UTC)

Let's wait and find out what BT and the WMO says. Jason Rees (talk) 22:28, 11 March 2023 (UTC)