Talk:Global warming hiatus/Archive 3

Archive 1

Archive 2

Archive 3

New Karl et al adjustments raise past temps, hence decrease overall GW

I added this bit to Karl et al, from Justin Gillis's NYT report on same, rather an eye-opener:

The corrected data set also "makes the temperature increase of the past century appear less severe than it does in the raw data", by about 0.42 °F (0.23 °C), according to NOAA climate scientist Russell S. Vose. Cited to Global Warming ‘Hiatus’ Challenged by NOAA Research , New York Times, June 4, 2015.

WMC reverted, commenting "perfectly reasonable edits if in a different article. This isn't the intrumental temperature record article."

I submit that it's perfectly reasonable for here, too. If the Karl 2015 adjustments are accepted, the overall GW since 1880 decreases by about 20%, a substantial effect. It would seriously mislead our readers to imply that the only effect of the new NOAA adjustments was to make the Pause go away.

I agree it should be added elsewhere as well. Has anyone seen a more formal writeup of this change? Preferably with a before & after graph, 1880 to 2014? We should add that chart here, too, under the current one in the lede.

Incidentally, our cite of the Karl paper currently omits the 8 et als. Cheers, Pete Tillman (talk) 18:08, 12 June 2015 (UTC)

It would seriously mislead our readers to imply that the only effect of the new NOAA adjustments was... - this page isn't about the paper. Its been edited in recently, but don't get confused. Arguably this page shouldn't really even exist; it should just be a subsection of the temperature record William M. Connolley (talk) 19:48, 12 June 2015 (UTC)

Fair enough -- we can certainly cross-ref (and should ).

But, in the here-and-now, the page DOES exist. So, if we are discussing Karl et al, we need the GW implications too. This is pretty straightforward, WMC. Pete Tillman (talk) 19:52, 12 June 2015 (UTC)

The urgency of the matter is tied to climate sensitivity, and the implication of actual temp increase being lower than anyone previously thought is that climate sensitivity is higher than we thought. After all, we have multiple lines of evidence of warming from Retreat of glaciers since 1850 to thawing of Ötzi the ice man to Extreme weather to many others. Wherever we talk about actual temp increase being lower than thought, we shoul also mention that the system is that much more sensitive than we thought. Presumably there's RS for this, but I haven't gone looking for them yet. NewsAndEventsGuy (talk) 20:02, 12 June 2015 (UTC)

WMC being well aware of the context, he may have missed PT's confusion and hence the unjustified excitement: the clue is that Russell S. Vose didn't say that the new correction "makes the temperature increase of the past century appear less severe than it does in the raw data". Careful reading of the NYT is needed. . . dave souza, talk 20:23, 12 June 2015 (UTC)

b.t.w. a handy before-and-after graph showing the effect of the adjustments on earlier years is Figure 2.4. Not completely up to date, but shows the same principle. . dave souza, talk 20:37, 12 June 2015 (UTC)

• From The NYT:

However, Russell S. Vose, chief of the climate science division at NOAA’s Asheville center, pointed out in an interview that while the corrections do eliminate the recent warming slowdown, the overall effect of the agency’s adjustments has long been to raise the reported global temperatures in the late 19th and early 20th centuries by a substantial margin. That makes the temperature increase of the past century appear less severe than it does in the raw data.

If you just wanted to release to the American public our uncorrected data set, it would say that the world has warmed up about 2.071 degrees Fahrenheit since 1880,” Dr. Vose said. “Our corrected data set says things have warmed up about 1.65 degrees Fahrenheit. Our corrections lower the rate of warming on a global scale.”

Seems pretty straightforward, Dave. If the past was warmer, delta-T (1880-2014) is less. Unpack your remark, please. Thanks, Pete Tillman (talk) 22:40, 12 June 2015 (UTC)

Vose is reported in the NYT to say, "the overall effect of the agency’s adjustments has long been to raise the reported global temperatures in the late 19th and early 20th centuries by a substantial margin" (my italics). NOAA has been making adjustments to raw data for a long time. Dave said, "Vose didn't say that the new correction "makes the temperature increase of the past century appear less severe..."" (again my italics) It seems pretty clear to me. You just have to read all the words. --Nigelj (talk) 23:41, 12 June 2015 (UTC

Thanks Nigelj, the RC gospel on this covers the point well in the caption to Figure 2 from Karl et al (2015). Fig 2A shows that the total effect of the recent improvements is very small, to my eye 2B showing relationship of corrected data to raw data is very similar to Figure 2.4 from TAR (2001), though of course the newer paper shows about 15 more years of warming. Note that the text of the TAR shows reasons for corrections which have been repeated in reports on Karl et al. . . . dave souza, talk 06:46, 13 June 2015 (UTC)

Another example why we should work harder at following FAQ twenty-one NewsAndEventsGuy (talk) 02:20, 13 June 2015 (UTC)

---

[convenience break]

Thanks to all for the comments. On carefully rereading it, Vose's statement is (to me) ambiguous, and who knows if the newspaper got all the details right. Bottom line: WMC was right that it doesn't belong here. It might be interesting to pursue in the history of adjustments to the temp record. Best, Pete Tillman (talk) 22:26, 13 June 2015 (UTC)

• Here's Zeke Hausfather at Yale Climate Connections on Karl et al 2015: Whither the pause? NOAA report shows no recent slowdown in warming , June 5, 2015.

Hausfather also quotes Vose, and helpfully includes the "before and after" chart of the new corrections from Karl et al, which I've just added to the article. Best, Pete Tillman (talk) 21:39, 3 July 2015 (UTC)

Thanks for uploading that graph, Fig 2B from Karl et al.. Don't know how long it'll stay available as non-free, pity it wasn't published by NOAA as it might them be public domain. As well as some reorganisation in progress, have clarified the caption to be consistent with the paper's description:
For the full period of record (1880–present) (Fig. 2), the new global analysis has essentially the same rate of warm- ing as the previous analysis (0.068°C dec−1 and 0.065°C dec−1 respectively; Table S1), reinforcing the point that the new corrections mainly have an impact in recent decades. How- ever, it is also clear that the long-term trend would be significantly higher (by 0.085°C dec−1; Fig. 2B) without corrections for other historical biases as described in (26). . . dave souza, talk 22:16, 3 July 2015 (UTC)

Thanks for cmts, Dave. I took the "bias" out of the cap, as this is likely to mislead general readers, who see bias as bad. Well it is, but technically so ;-] Otherwise, appreciate WIP, will chk back after I finish cleaning off aprrox 10,000 spider webs.... Pete Tillman (talk) 23:40, 3 July 2015 (UTC)

Ed Hawkins on Karl et al 2015

An interesting discussion at his Climate Lab Book: A spectrum of global temperature trends.

Karl et al.’s conclusion that the warming during the most recent 15 years compared to the second half of the 20th century ... is broadly correct, although I would suggest that ‘similar to’ is more appropriate than ‘at least as great as’.

But, there has clearly been a slowdown in the rate of warming when compared to other periods, e.g. those centred on the 1990s.

So, it's a criticism of detail, but then, it's pretty obvious that the timing of publication of Karl et al. had a political element. Good discussion, too.--Pete Tillman (talk) 02:32, 29 June 2015 (UTC)

Pete, once again this is your own political interpretation and doesn't follow the WP:TALK guideline, or indeed WP:NOTAFORUM policy: the blog isn't a reliable source, and the comments even less so. Got any reliably sourced proposals for article improvement? . . dave souza, talk 06:26, 29 June 2015 (UTC)

Hawkins is certainly RS under the expert exemption, as you know, Dave. And your postings are always so pure and ideology-free, right? Pete Tillman (talk) 17:31, 29 June 2015 (UTC)

I've not used RealClimate as a source here, but given your support for expert opinion in blogs I'll reconsider that. As for this brief post by Hawkins, you seem to be taking part out of context, and the "political element" is your speculation with no reliable source. As for ideology, you seem to be getting very WP:BATTLEFIELD: try to comply both with conduct policy and with policy on giving due weight to mainstream science. . . dave souza, talk 18:23, 29 June 2015 (UTC)

I'm fine with RC as a source, depending on the author, of course. Often see it used elsewhere in CC area. I used a snippet from Ed H to tweak the caption of our Fig 2. Cheers, Pete Tillman (talk) 19:39, 6 July 2015 (UTC)

I removed that; it wasn't obvious why it was better than the paper William M. Connolley (talk) 20:20, 6 July 2015 (UTC)

Pete seems to have misread the blog post, that could have been clarified by looking at the paper. Note that the corrections for bias pre 1940, which result in higher temps and so a slower rate of warmign than the raw data, are as described in T. M. Smith, R. W. Reynolds, Extended reconstruction of global sea surface temperatures based on COADS data (1854-1997). J. Clim. 16, 1495–1510 (2003). doi:10.1175/1520-0442-16.10.1495 – in other words, corrections made 12 years ago.
As Vose said, "the overall effect of the agency’s adjustments has long been to raise the reported global temperatures in the late 19th and early 20th centuries by a substantial margin." [assuming Pete's copy and paste didn't introduce errors] Bolding added to point out that this isn't an effect of "the new corrections" as Pete wrote in the caption. . . dave souza, talk 21:06, 6 July 2015 (UTC)

If I misread it, so did Hawkins. More likely, we are both correct. Vose's "long" is (apparently) Karl et al's "new corrections" on our Fig.2. Or something like it. Dave, would you care to comment? Pete Tillman (talk) 17:27, 8 July 2015 (UTC)

I've re-read the blog post by Hawkins, and can't see any mention of the pre-1940 period. Blog comments are never a r.s. dave souza, talk 20:39, 8 July 2015 (UTC)

WMC, you have strenuously resisted any reference to criticisms of this new and controversial paper. Why is that? You've already reverted out refs to LA Times, Curry and NY Times accounts, ims. Now Hawkins too. Seems to verge on contentious editing. Pete Tillman (talk) 17:27, 8 July 2015 (UTC)

I don't think the paper is controversial; quite the contrary, its been widely accepted, often with "meh" William M. Connolley (talk) 19:03, 8 July 2015 (UTC)

• [OD] your personal opinion is noted. Nevertheless, you have reverted out multiple RS crits of the article, and I haven't even tried with the political stuff ... What, youhadn't noticed the politics of CC? Best, Pete Tillman (talk) 20:21, 8 July 2015 (UTC)

Global warming pause myth

• John Abraham (September 18, 2015). "In a blind test, economists reject the notion of a global warming pause". The Guardian. Retrieved September 18, 2015. Quote: "Four separate studies have now demolished the myth of a global warming ‘pause’"

Perhaps this source can be worked into the article as a secondary source. Are we now at the point the article can more strongly assert there has been no pause? It appears to be unequivocal, among the science community. -- GreenC 14:51, 18 September 2015 (UTC)

NOAA undue weight

The NOAA paper that is given undue weight is titled. "Possible artifacts of data biases in the recent global surface warming hiatus" So first of all this is purely theoretical and is not in any way "corrections" or the "new data". It is instead "possible" Second. The title of the paper also admits that the raw data shows the hiatus. The IPCC agrees. As do all the data sets. The NOAA paper is by definition an out-liar and contradicts the climate data. The whole article needs an overhual

Have you considered reading the paper, rather than just the title? William M. Connolley (talk) 07:51, 9 November 2015 (UTC)

It looks like this article will need something of an overhaul in a month or so. It seems that 2015's global mean temperature might be interesting.[1] --Nigelj (talk) 15:46, 18 November 2015 (UTC)

But... that's a bias source, as a semi-skeptic in charge of a science body would tell you, an “infinitesimal” amount of human-produced carbon dioxide can't be blamed for the planet heating up, and anyway "The data is skewed. The data is biased. That’s not good science. When I see government agencies skewing the data, that makes me very suspicious.” Not only that, but even if this is a record year, that means it's the start of a new hiatus. . . . dave souza, talk 17:33, 18 November 2015 (UTC)

Still undue weight from this NOAA speculative paper. The "Hiatus" is in the measured data. That's the subject of teh article. The NOAA stuff should be in a little subsection. The hiatus is sourced many times already. Here are a few more.

http://www.nature.com/news/climate-change-the-case-of-the-missing-heat-1.14525 http://www.latimes.com/science/la-sci-sn-global-warming-hiatus-20150603-story.html http://www.reuters.com/article/us-climatechange-summit-britain-idUSKCN0RD0YN20150914 http://www.bbc.com/news/science-environment-24173504 — Preceding unsigned comment added by 24.207.135.183 (talk) 21:49, 5 December 2015 (UTC)

Rename article to Global Warming Hiatus Myth

Folks, I guess you really tried to write an unbiased article about legitimate conclusions that the current period is actually non-warming, but you couldn't do it. This article only serves to discredit those interpretations of the data. Please change the title to reflect the true purpose of the article. — Preceding unsigned comment added by Wmjohn6217 (talk • contribs) 05:35, 19 November 2015 (UTC)

Correction, we tried to write an unbiased article about periods of slower but continuing warming, in accord with IPCC and other sources. But I hear what you're saying. Can you point to high level RSs that use variants of "myth", "misconception", etc? Personally, I'm not too excited about referencing scientific misconceptions as "myths", since "myth" as so susceptible to being understood as an evidence-free metaphorical interpretation of casual observation. That isn't the case with the professional literature's discussion of this subject.NewsAndEventsGuy (talk) 06:39, 19 November 2015 (UTC)

It's still an issue that the naming of this article doesn't distinguish between /A/ "global warming hiatus" (of which there seem to have been several, uncontroversially) versus "THE pause", this controversy where the argument for a hiatus is recently losing out to better data. The lede for an article on "global warming pause" might start, "The global warming pause is/(was?) a hypothesized global warming hiatus ...." and would go into some detail about the controversies, leaving most of the technical details to global warming hiatus. Yakushima (talk) 04:42, 24 December 2015 (UTC)

POV language -- "corrections"

I'm struggling to come up with the right language here. The word "corrections" is indeed used in the source. The problem is that it appears to be unproven whether or not the corrections are, in fact, correct. The source makes that clear, too, with its discussion of debate about whether or not to adopt the "corrections" more broadly. If someone had managed to (say) add 2 and 2 and come up with 5, calling it a "correction" would be clearly advisable. I don't want to say "changes" or "modifications", as that would tend to imply the opposite -- that the numbers are being fudged.

What about using the word "reinterpretations"? Any better ideas? CometEncke (talk) 17:35, 29 January 2016 (UTC)

• As this reliable source states, scientists rely on a process called “homogenization.” – Johnson, Scott K. (24 January 2016). "Thorough, not thoroughly fabricated: The truth about global temperature data". Ars Technica UK. Retrieved 29 January 2016. {{cite web}}: Invalid |ref=harv (help) Suggest adding this as a source, it specifically discusses the claims that there has been "no significant global warming for the past 18 years" as stated by Ted Cruz, and Lamar Smith's campaign with his attempt to subpoena NOAA scientists for their e-mails. That's an aspect of this topic the article should mention. . dave souza, talk 17:54, 29 January 2016 (UTC)

Sorry, my note could have been more clear. I was referring to the chart at the right of the article, which discusses "corrections" to the temperatures from approximately 1880-1940. CometEncke (talk) 16:16, 30 January 2016 (UTC)

There is no requirement nor expectation that "corrections" result in something "correct" - corrections are attempts to reduce known problems with the data, not to reach data heaven, a state of perfect and flawless grace. Also see Nirvana fallacy. --Stephan Schulz (talk) 14:43, 1 February 2016 (UTC)

Hello again, and welcome to the party! Thanks for making things a bit more obvious. I have to confess they are still not entirely so, at least not to me. The NYT source in particular used the word "adjustments" when it was not directly quoting -- the same word I am drawing so much flack for switching to. CometEncke (talk) 17:47, 1 February 2016 (UTC)

There are two separate points here - one is if "adjustments" or "corrections" is better, and one where you changed a literal quote. Regardless of the first point, the second has a clear answer: Don't. --Stephan Schulz (talk) 18:31, 1 February 2016 (UTC)

OK, got it, the one about "pointed out in an interview . . ." is actually a quote; I missed that. Sorry. The first two, if I'm not mistaken, are up to our editorial discretion. CometEncke (talk) 20:04, 1 February 2016 (UTC)

Very good, I appreciate it. Now, what's your take on my comment above? Why do you think "adjustments" - which can be any arbitrary change - is better than "corrections" - changes made to correct specific problems? The NYT, btw, uses both terms in the editorial voice. The peer-reviewed article in Science uses "corrections" exclusively, as far as I can see. --Stephan Schulz (talk) 22:46, 1 February 2016 (UTC)

There are actually two questions there: why not "corrections" and why "adjustments"? I'll start with the second one -- I don't actually have a strong opinion about it. I've been struggling to find a word that best describes what is going on, without prejudging the correctness. The only two I've come up with so far are "adjustments" and "reinterpretations". It is actually possible that "reinterpretations" is better as it suggests that he same data are being used, but are being looked at in a different way. In the end, I'd be fine with either of those words, or perhaps with a third word no one has come up with yet.

Now, for "corrections". I don't think we know which interpretation is truly correct. Many RS use "corrections", maybe even a majority, but Wikipedia has a tradition of using more neutral language when not quoting. In thinking about the issue, one also has to consider that the authors of peer-reviewed articles are still going to have biasses. If they want the corrections to be adopted, they are more likely to use the word "corrections". And that brings me to my next point -- the NYT source talks about a discussion of whether or not the "corrections" should be "adopted more broadly." But if they were truly just corrections, that would be an absurd discussion. A true correction would of course be adopted. That suggests to me that "correction" is not an accurate description of what is really going on. CometEncke (talk) 06:05, 2 February 2016 (UTC)

Odd spin in your sentence "one also has to consider that the authors of peer-reviewed articles are still going to have biasses". The whole point is that the data has biases, and corrections for these biases are needed for Homogenization (climate) when relating data points in a dataset. The correction methodology is published in peer-reviewed papers. . . dave souza, talk 09:52, 2 February 2016 (UTC)

To clarify the point, I've amended the lead and relevant section to be clear that we're discussing homogenization corrections. . . . dave souza, talk 10:41, 2 February 2016 (UTC)

Two comments, I'll start with the change itself. I have no POV objections to "Homogenization." I tried to look at the sourcing but stopped when it asked for registration. I'll assume you've done your homework in that regard. Secondly, about "spin." Can we avoid that type of characterization when it's unclear if it's true and it is clear that it's not even necessary. Characterizing my words that way does not help come to an agreement and does make the environment a little less friendly. So please don't. CometEncke (talk) 07:36, 3 February 2016 (UTC)

Thanks for your appreciation of "homogenisation", the linked article is quite informative. As for the allegation that "the authors of peer-reviewed articles are still going to have biasses", glad it's not your characterisation of the work of scientists who clearly are trying to overcome biases in the data, irrespective of the overall effect of showing less warming than the raw data indicates. I'm sure a friendly environment will be enhanced by assuming good faith and avoiding unsourced allegations about the integrity of scientists. . . dave souza, talk 18:47, 3 February 2016 (UTC)

I didn't question their integrity. I said they have biases too. Which I would also say about every person on the planet. "Allegation" my ass. CometEncke (talk) 22:27, 3 February 2016 (UTC)

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"Ending" "Scientific credibility"

No, I don't think that's fair. Scientific credibility of what? The fact that there were some years where y/y growth was lowered or negative? Obviously not. The idea that recent lower or negative y/y growth was permanent? It certainly lessened the credibility of that, at a minimum; I still would not say "ended"; not clear to me that it had much credibility in the first place, and to the extent that it did, I would not say that any single year would "end" or even "largely end" it. The idea that the years of lower growth suggest that relatively higher growth seen from roughly 1970-1998 was actually greater than the long-term trend line? Certainly it lessened the credibility of that, but I'd suggest that particular notion should still be considered credible. Just as there are down periods, there are also up periods; nothing surprising about that. CometEncke (talk) 06:58, 1 February 2016 (UTC)

I would further note that the statement itself is vague as it doesn't explain which notion's credibility it thinks is ending. CometEncke (talk) 07:06, 1 February 2016 (UTC)

It is hard to give anything precise; but the intent is clear I think. That the concept is no longer credible William M. Connolley (talk) 10:32, 1 February 2016 (UTC)

But that's exactly the problem. In science, if one says a concept has no credibility, one has to say what the concept is. Otherwise, one is no longer doing science.CometEncke (talk) 12:47, 1 February 2016 (UTC)

I'm going to comment on a meta level on this one, then try my best to leave well enough alone. Science, as I'm sure you know, deals with observable facts, and models, theories, hypotheses, etc. to explain those facts. But in AGW and related fields, there is a political side that gets mixed in with it. So, perhaps a statement such as "the hiatus has no credibility" is intended to be understood on a political level, to make AGW opponents look bad. For some readers, it may indeed have that effect. But, for a reader who understands science and is used to thinking logically, the effect will actually be the opposite. A reader like that will understand that the statement is too vague to have any scientific meaning, and also that it must come from an AGW supporter. Therefore, that reader is likely to actually be pushed a little bit in the direction of thinking that AGW supporters have a tendency to push their case beyond what facts actually show. That's how it comes across to me. That said, I hope I can restrain myself from rewriting, reverting, etc. this particular sentence. In the end, it comes across exactly as I described above. But I think I can do more good by explaining that than I can by fighting over it. So that's where I'll try to stop. CometEncke (talk) 13:05, 1 February 2016 (UTC)

Matthew 7:3 seems appropriate here... --Stephan Schulz (talk) 14:46, 1 February 2016 (UTC)

To clarify the point, I've expanded the sentence to say "The warmth of 2015 largely ended any remaining scientific credibility of claims that the supposed "hiatus" since 1998 had any significance for the long term warming trend." Hope that helps. . dave souza, talk 10:38, 2 February 2016 (UTC)

I still don't think that's accurate. There were different types of such claims -- claims that there was no long-term warming, which IMO never had any cred in the first place, and claims that the lower warming of 1998-2014 showed that any estimates based on the 1970-1998 trend line were overestimates. Such claims always were credible and still are. To illustrate the point, recent adjustments, homogenization, or whatever you want to call them that result in no hiatus also result in lower 1970-1998 warming. That said, I will continue trying not to edit this particular passage. CometEncke (talk) 07:58, 3 February 2016 (UTC)

Were there any estimates of a warming trend based on "the 1970-1998" trend line? Please cite a source. The 2001 IPCC Third Assessment Report Chapter 2 discussed warming over the century, in which "The two main periods of warming in all three series are between about 1910 to 1945 and between 1976 to 2000", while cautioning that "trends over such short periods are very susceptible to end effects so the values in Table 2.1, and Table 2.2 below, should be viewed with caution for these periods." While 1998 was the warmest year, on smoothed curves it appears as an outlier. . dave souza, talk 18:40, 3 February 2016 (UTC)

Look, this is a talk page. I gave my opinion. As I said, I am going to try my best not to edit that passage. The claim in the passage makes no sense under any reasonable interpretation, for reasons I've explained. But if you want it in there, I'm not stopping you. CometEncke (talk) 22:24, 3 February 2016 (UTC)

Fyfe, Meehl, et al (including Mann) settled on a 1972 to 2001 baseline and concluded ″we find that the surface warming from 2001 to 2014 is significantly smaller than the baseline warming rate.″ and ″that Research into the nature and causes of the slowdown has triggered improved understanding of observational biases, radiative forcing and internal variability.″ ... ″The legacy of this new understanding will certainly outlive the recent warming slowdown.″ [2] Poodleboy (talk) 08:59, 15 July 2016 (UTC)

Fyfe, et al does dispute Karl

Fyfe,et al, very specifically and pointedly does dispute Karl's attempts to dispute the pause ″It has been claimed that the early-2000s global warming slowdown or hiatus, characterized by a reduced rate of global surface warming, has been overstated, lacks sound scientific basis, or is unsupported by observations. The evidence presented here contradicts these claims.″ [3] And they do so, using Karl's data. Poodleboy (talk) 09:51, 15 July 2016 (UTC)

They're already covered in the article. In the paper, they reject the idea that warming has "paused" as "unfortunate" wording, and propose that it's better described as " 'reduced rate of warming', 'decadal fluctuation' or 'temporary slowdown' — all try to convey the primary mechanism involved, which in the recent example is likely to be internal decadal variability." So, no pause. . dave souza, talk 11:31, 15 July 2016 (UTC)

The hiatus has always been in the trend, not in the warming, because heat was still being stored into the oceans, although apparently at a lower rate. There has been no convincing report of the missing heat. The phenomenon is real, and the leading hypotheses account for the mid-century cool period/hiatus as well. Even in the new Karl data, the trend in the hiatus is not distinguishable from zero, unless, of course, you relax the standard of statistical significance from 0.05 to 0.1. Fyfe, et al, explain that Karl included the mid-century cooling in the baseline, and that they consider that physically unjustified. Fyfe, Meehl, England, Mann, Santer, Flato, Hawkins, Gillett, Xie, Kosaka and Swart could hardly have been more specific than "the evidence presented here contradicts those claims" without personally attacking the integrity of the Karl. Karl improved his data without materially changing the evidence of the pause and then put forward an argument that was little more than spin, and parlor tricks against a straw man.

The generous interpretation is that believers in the community simply panicked, because even though the warming is still continuing, real questions are involved, as Fyfe, et al, point out: "The recent decadal slowdown, on the other hand, is unique in having occurred during a time of strongly increasing anthropogenic radiative forcing of the climate system. This raises interesting science questions: are we living in a world less sensitive to GHG forcing than previously thought, or are negative forcings playing a larger role than expected? Or is the recent slowdown a natural decadal modulation of the long-term GMST trend? If the latter is the case, we might expect a 'surge' back to the forced trend when internal variability flips phase." In a couple years, it might be clear that the pause has ended and we are in another the positive phase of the decadal ocean modes, but the significance of the questions raised by the pause will remain. Poodleboy (talk) 16:53, 15 July 2016 (UTC)

How about the 'generous' interpretation that two groups of scientists disagreed with each other other over the their interpretation of the figures? And that we'll probably need a couple more years yet to see a few other studies as well and the matter is fully settled? No assumption that one side is right and the other wrong. No assumption that one group had some existential fear that requires them to believe falsehoods and try and propagate them, and the other holds the sword of light and are marching forward into the bright future like workers in some soviet poster. Just a disagreement which is documented in the article in accord with neutral point of view. Dmcq (talk) 20:41, 15 July 2016 (UTC)

And no assumption that one side is funded by oil. There was a considerable mainstream literature on the hiatus/pause and multi-decade ocean modes, plus a lot of government funding was tied to studying it. Thus the quick response and the pointers on how to properly interpret the data Poodleboy (talk) 20:49, 15 July 2016 (UTC)

Wikipedia is not a forum for your own thoughts and this page is for discussion on improvements to the article. If you have some citation from a reliable source which asserts that one side was unduly influenced in some way, or even that such effects have been acting in any way in the scientific debate, then produce it. If you have no evidence for something then just leave it out. Dmcq (talk) 21:08, 15 July 2016 (UTC)

citatation needed: many such periods

A citation is needed and unlikely to be found for

"In the current episode of global warming many such periods appear in the surface temperature record,"

The current episode of global warming is usually taken to be the 20th century or the latter half of the 20th century when anthropogenic CO2 become important. So there is one other period, the mid-century cool period, "one" is not usually considered many. Poodleboy (talk) 01:23, 16 July 2016 (UTC)

As cited, "Fifteen-year-long hiatus periods are common in both the observed and CMIP5 historical GMST time series", "Box TS.3: Climate Models and the Hiatus in Global Mean Surface Warming of the Past 15 Years", IPCC, Climate Change 2013". . dave souza, talk 03:08, 16 July 2016 (UTC)

The CIMP5 are models and not part of the surface temperature record. The GMST time series is much longer than "the current episode of global warming". How long are you arguing the current episode of global warming is? Poodleboy (talk) 03:20, 16 July 2016 (UTC)

IPCC AR5 actually discusses the GMST of the pliocene, what evidence is there that there are many rather than just one 15 year hiatus during the current episode of global warming. Poodleboy (talk) 08:40, 16 July 2016 (UTC)

Also cited, p. 37 "Despite the robust multi-decadal warming, there exists substantial interannual to decadal variability in the rate of warming, with several periods exhibiting weaker trends (including the warming hiatus since 1998) (Figure TS.1)." That figure covers at most 1850 to 2012. Chapter 2 pp. 192–193 has "Much interest has focussed on the period since 1998 and an observed reduction in warming trend, most marked in NH winter (Cohen et al., 2012). Various investigators have pointed out the limitations of such short-term trend analysis in the presence of auto-correlated series var- iability and that several other similar length phases of no warming exist in all the observational records and in climate model simulations (Easterling and Wehner, 2009; Peterson et al., 2009; Liebmann et al., 2010; Foster and Rahmstorf, 2011; Santer et al., 2011)." As it happens, SkS, which points out multiple short term "slowdowns", cites Santer et al., 2011 which says their "results show that temperature records of at least 17 years in length are required for identifying human effects on global-mean tropospheric temperature." Remarkably prescient considering the 2014 jump back on track for warming, which continues...... dave souza, talk 09:16, 16 July 2016 (UTC)

The do appear to be stretching for that claim. Although I don't see how they can fit many 15 year periods of lesser warming in the 1850 to 1900 range of natural warming. I withdraw the citation needed, can you put some of this specific support in the existing citation? The pause may have ended, we shouldn't call it until after we see the response to the next la Nina's. Poodleboy (talk) 18:36, 16 July 2016 (UTC)

citation needed for PDO being neutral from 1971 to 2000 and all the warming being due to human causes.

A citation is needed for:

It had last been neutral between 1971 and 2000 when temperatures increased due to human cause

Two issues, the ocean models, including the PDO are considered to have usually been positive during this period, not neutral. The leading hypotheses have these ocean modes being responsible for the rapid warming. Human's are causing the long term trend, but internal variation is considered responsible for the periods of rapid warming and the slowdowns. Here is just one of the results coming to terms with the midcentury cooling and the recent pause in the journal Science. Its hiatus hypothesis argues for a heat sink and cyclic modes in the Atlantic rather than the Pacific. The press release contained these two statements:

"Rapid warming in the last three decades of the 20th century, they found, was roughly half due to global warming and half to the natural Atlantic Ocean cycle that kept more heat near the surface."

"The authors dug up historical data to show that the cooling in the three decades between 1945 to 1975 – which caused people to worry about the start of an Ice Age – was during a cooling phase. (It was thought to be caused by air pollution.)"

Here are the press release and paper. [4] [5] Poodleboy (talk) 01:41, 16 July 2016 (UTC)

That's under the outline of the Karl et al. findings, and the citation says "The only time the PDO was neutral in recent history was between 1971 and 2000, Fyfe said. In that case, the temperature record reflects the response to human-caused climate change, he said." You're citing a different paper, if you want to add that then you're welcome to add a summary referring to it. . dave souza, talk 03:20, 16 July 2016 (UTC)

Strangely, you may be right about that source supporting that statement. I would argue that Climate Wire must have misunderstood Fyfe, because they didn't quote him. Here is the pertinent part of the Fyfe's peer review paper, quoting the whole paragraph for context (emphasis mine):

The big hiatus and warming slowdown periods correspond to times during which the dominant mode of decadal variability in the Pacific — the IPO — was in its negative phase. In the intervening period the IPO was in its positive phase. Recent modelling and observationally based studies indicate an important role for Pacific decadal variability in modulating temporal changes in GMST. Based on both of these factors — the relatively steady increase in net anthropogenic forcing over the period 1972 to 2001, and the consistent sign of the IPO during this time — we argue that as a baseline for evaluating whether the surface warming rate is unchanged in the early twenty-first century, 1972–2001 is a preferable choice to 1950–1999. Using this more physically interpretable 1972–2001 baseline, we find that the surface warming from 2001to 2014 is significantly smaller than the baseline warming rate. [6]

unless Fyfe is out of sync with his own paper, Climate Wire must have gotten it wrong. Fyfe must have been referring to the long term trend as reflecting the response to human caused climate change. We probably should go with the peer review source. Poodleboy (talk) 04:07, 16 July 2016 (UTC)

PDO ≠ IPO, so looks like you're doing some original research.... . dave souza, talk 09:25, 16 July 2016 (UTC)

No, I am just understanding the range of terms used in the literature for the same phenomena. Just like the big hiatus is the mid century cool period. What Fyfe actual wrote should take precedence over Climate Wire didn't quote.Poodleboy (talk) 18:15, 16 July 2016 (UTC)

Interdecadal Pacific Oscillation vs. Pacific decadal oscillation strongly suggests that the two are different if related phenomena. --Stephan Schulz (talk) 19:42, 16 July 2016 (UTC)

It doesn't appear that the PDO could be neutral while the IPO is positive. The latter encompassing the former. Poodleboy (talk) 23:17, 16 July 2016 (UTC)

Per Trenberth in the journal Science There is also a strong decadal variability is the Pacific Ocean, part of which is the Pacific Decadal Oscillation (PDO). The PDO is closely related to the Interdecadal Pacific Oscillation (IPO) but has a more Northern Hemisphere focus. Observations and models show that the PDO is a key player in the two recent hiatus periods. His A Staircase of Rising Temperatures figure shows that the PDO was in its positive phase.[7]Poodleboy (talk) 23:36, 16 July 2016 (UTC)

Well, first, do we now agree on not the same phenomenon? And secondly, you now seem to be saying that 0+X=1 can't have a solution, because the sum is "strongly linked" to both components, and the first one is neutral... --Stephan Schulz (talk) 05:16, 17 July 2016 (UTC)

It is clear there is something erroneous about the source and the statement in the article that was supported by it. The PDO was in its positive phase over nearly all the 1972 to 2000 period, and all the warming being due to human causes is not true for that period since much of the warming over that period is being attributed to natural internal variation. Nearly all the longer term trend is anthropogenic, but that is not the implication of the statement.Poodleboy (talk) 07:03, 17 July 2016 (UTC)

citation needed: misleading narrative, as in the Reuters headline

The Mother Jones mentions "piling on", but does not support that this statement:

"There was a surge in media interest setting a misleading narrative, as in the Reuters headline "Climate scientists struggle to explain warming slowdown"

Mother Jones does not say that the Reuters headline was misleading, and frankly it isn't. Even 2016 publications such as Fyfe, Meehl, et al, still refer to the slowdown, and several publications in the last couple years present hypotheses to explain or dispute the hiatus. Poodleboy (talk) 01:29, 16 July 2016 (UTC)

As Mooney says, it's a misleading narrative: "At the time, many critics pointed out that these assertions were scientifically misleading", and he quotes Dennis Hartmann of the University of Washington, "the trend over a 15-year record is not really very meaningful, because of the natural interannual variability of the climate system". Which is pretty much what Fyfe et al. say, Against that, you're putting your own interpretation, which is original research at best. . dave souza, talk 03:04, 16 July 2016 (UTC)

Actually Fyfe, et al, point out: "The recent decadal slowdown, on the other hand, is unique in having occurred during a time of strongly increasing anthropogenic radiative forcing of the climate system. This raises interesting science questions: are we living in a world less sensitive to GHG forcing than previously thought, or are negative forcings playing a larger role than expected? Or is the recent slowdown a natural decadal modulation of the long-term GMST trend? If the latter is the case, we might expect a 'surge' back to the forced trend when internal variability flips phase."Poodleboy (talk) 04:12, 16 July 2016 (UTC)

Indeed this small scale fluctuation raises interesting questions, which Fjfe et al. are right to highlight. At the same time, as they state at the outset, "A large body of scientific evidence — amassed before and since the Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC AR5)1 — indicates that the so-called surface warming slowdown, also sometimes referred to in the literature as the hiatus, was due to the combined effects of internal decadal variability and natural forcing (volcanic and solar) superimposed on human- caused warming2. Given the intense political and public scrutiny that global climate change now receives, it has been imperative for scientists to provide a timely explanation of the warming slowdown, and to place it in the context of ongoing anthropogenic warming. Despite recently voiced concerns, we believe this has largely been accomplished." The "struggle to explain" was part of the misleading "pause" narrative, which you seem to be reiterating. . .dave souza, talk 10:07, 16 July 2016 (UTC)

Except that the headline uses the "slowdown" narrative, which isn't misleading, and Chris Mooney doesn't say that it is, just that the major news service was part of "piling on". It is not clear what the actual quote is, a headline or something from an article. The Mooney article isn't sourced. Poodleboy (talk) 18:25, 16 July 2016 (UTC)

There's the point that by the time of that headline there were multiple explanations of the "slowdown", so hardly a "struggle to explain", more a question of the normal debates in science over a short term phenomenon subject to considerable measured variability. As cited in AR5. . . dave souza, talk 19:53, 16 July 2016 (UTC)

No, it was still a struggle, even in late 2014 there is a search for the "missing heat", and even a question as to whether it has been found today. Key hypotheses were published in 2015. Finding the truth is always a struggle.Poodleboy (talk) 23:57, 16 July 2016 (UTC)

Since "Finding the truth is always a struggle", why should it be headline news? See dogwhistle and man bites dog. . . dave souza, talk 08:07, 17 July 2016 (UTC)

That wasn't the news, the news was where the struggle was, i.e., about the slowdown, a phenomenon that drew considerable interest, and that helped advance the science and will improve the models in the future. When I search google scholar on climate change and struggle, nearlly all the references are about the climate models struggling to reproduce this or that. Is it the models struggling or is it the modelers, the model scientists? Our social intelligence does tend to anthropomorphize. Poodleboy (talk) 21:13, 17 July 2016 (UTC)

Your original research is irrelevant. . . dave souza, talk 21:33, 17 July 2016 (UTC)

What makes your original research so relevant? Poodleboy (talk) 21:46, 17 July 2016 (UTC)

no, not with that data set -- WMC

Fyfe, et al. used that data set and the parts relevant to the hiatus haven't changed, so the studies of all those authors are still valid. The trend during the hiatus still is still not significantly different from zero. It is just not statistically different from the long term trend either. Perhaps you didn't notice: "We obtain 1972 as the end year of the big hiatus (the period of near-zero trend in the mid-twentieth century) by constructing an optimal piece-wise bilinear fit to the NOAA-Karl data over the period 1950 to 2001." [8] Poodleboy (talk) 17:22, 22 July 2016 (UTC)

@Isambard Kingdom: edits as if he was unaware of Fyfe (Feb. 2016) perhaps because some how it hasn't officially been cited in the article. It has a rather distinguished set of consensus authors, many who have been lead authors for the IPCC Working Group I, John C. Fyfe, Gerald A. Meehl, Matthew H. England, Michael E. Mann, Benjamin D. Santer, Gregory M. Flato, Ed Hawkins, Nathan P. Gillett, Shang-Ping Xie, Yu Kosaka & Neil C. Swart. The title is "Making sense of the early-2000s warming slowdown"[9]. He has restored the claim about the NOAA-Karl data that they reject, and done so inappropriately in a figure, as if it were fact somehow obvious from the data and not mere opinion supported by the Karl argument that these authors and Trenberth [10] reject. The sentence should be removed from the figure, and if it is to be discussed and disputed, it should be in the article proper. Poodleboy (talk) 08:43, 25 July 2016 (UTC)

I added the Fyfe et al. citation that you suggested (thank you). It is similar to the Dai et al. citation that I added yesterday (and on which Fyfe is a co-author). I hope that helps. Note that Fyfe et al. don't reject the data, which they refer to it as of "high scientific value". instead Fyfe et al. seek an interpretation of the hiatus. Isambard Kingdom (talk) 13:02, 25 July 2016 (UTC)

Agreed, thanx, but this statement you restored to the figure Temperature anomalies in the updated NOAA dataset show no evidence of a slowdown in the rate of warming post 1998 is not quite right, is it? Fyfe, et al, had no problem finding the slowdown, using the NOAA-Karl data depicted. Poodleboy (talk) 20:14, 25 July 2016 (UTC)

Is that a caption taken from the source of the figure? To avoid OR and our own subjective analysis, I suggest paraphrasing the caption of the source of the figure. Isambard Kingdom (talk) 20:34, 25 July 2016 (UTC)

The figure is 2b in the Karl paper. The caption in this article is not the fig 2 caption, but the argument that the recent hiatus is within the 90% confidence range of the long term trend and thus not statistically significant is from that same Karl paper. Of course there are papers which use the more classical 95% confidence range like the IPCC AR5 did, and find that a trend of zero can not be ruled out. It is strange to associate the hiatus conclusion with a figure depicting the NOAA-Karl date that doesn't even depict the trends. That doesn't seem the place to start bringing in other result and figures that actually show the trends.Poodleboy (talk) 21:09, 25 July 2016 (UTC)

I've tried to fix up the caption. I think it is possible you've been misinterpreting what Karl et al. say. They find a slower upward trend in T since 1880 than was previous estimated. This slower trend is in line with the recent trend since 1998. This means, among other things, that there has been "no hiatus" or slow down in the recent trend. I hope that helps. Isambard Kingdom (talk) 21:31, 25 July 2016 (UTC)

You correctly summarize the Karl, et al, argument, but the figure is a strange place to be doing it, because other more prominent authors still see a hiatus in more recent publications based upon this same data, so it is not just a matter of eyeballing it. If this article is to be just a summary of a primary source, the Karl paper, doesn't WP:SECONDARY require us to defer to the reliable, published secondary source, Frye (2016) to interpret this data? "Wikipedia articles usually rely on material from reliable secondary sources. Articles may make an analytic, evaluative, interpretive, or synthetic claim only if that has been published by a reliable secondary source." Poodleboy (talk) 04:11, 26 July 2016 (UTC)

I would describe the Karl et al., the Fyfe et al., and the Dai et al. articles as primary (though Nature and Science articles have a special status, since those journals are widely read by the broader scientific community). The Trenberth commentary (which you suggested), however, is what I would call secondary. Anyway, I don't see a major problem, here, at least not compared to other Wikiarticles. Isambard Kingdom (talk) 13:08, 26 July 2016 (UTC)

Fyfe would be primary for Fyfe, but secondary for the Karl data. Let's not dip to the general wiki standard.Poodleboy (talk) 15:06, 26 July 2016 (UTC)

I've added citations to sources that interested you. Of course, you are welcome to add more. Thank you. Isambard Kingdom (talk) 15:11, 26 July 2016 (UTC)