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Comments 72351 to 72400:

72351. John Hartz at 05:13 AM on 19 October 2011
       SkS Weekly Digest #20
       Lest there be any confusion, the above Toon of the Week satirizes how Fox News and other like media outlets perpetuate the myth of scientific debate by giving equal weight to the findings of legitimate scientists and the opinions of non-scientists. The fact that the couch potato in the toon is named "Roger" has absolutely nothing to do with Dr. Roger Pielke Sr., a distinguished scientist.
72352. jg at 03:43 AM on 19 October 2011
       Comparing Global Temperature Predictions
       Bern, I will work on a variation of the animation that includes your suggestion. jg
72353. muoncounter at 03:43 AM on 19 October 2011
       Continued Lower Atmosphere Warming
       DM#82: "it is incorrect to assert that one trend IS different from another unless the difference in trends is statistically significant." Could not agree more with that statement. This is essentially a signal processing problem, that of extracting meaningful changes in trends from noise. As such, this working definition of statistical significance is relevant: Statistical significance can be considered to be the confidence one has in a given result. In a comparison study, it is dependent on the relative difference between the groups compared, the amount of measurement and the noise associated with the measurement. In other words, the confidence one has in a given result being non-random (i.e. it is not a consequence of chance) depends on the signal-to-noise ratio (SNR) and the sample size. If we cannot establish the significance of the supposed change in trend, then how can we say that we are confident in its existence? And if we are not confident in its existence, how can we base any conclusion on it?
72354. JMurphy at 03:07 AM on 19 October 2011
       OA not OK part 20: SUMMARY 2/2
       With regard to the Erl Happ fiasco (as mentioned by Philippe Chantreau), I think the result for WUWT was even more of a joke because Erl Happ seemed to suggest (in a tongue-in-cheek manner) that the cock-up might have been due to one of three possibilities : one of which being that he may have written it after having drunk a glass of wine. I can't remember the exact details (and I can't bare to return to WUWT to check - you have to wade through so much treacle to find what you want), but Watts used that supposed admission of drunkenness as a get-out clause to blame it all on the author, and to try to scrape back some credibility by banning Erl Happ from posting any more pieces. First Goddard, now Happ - how many more before even Watts's friends admit the denial-reality of his website ?
72355. Alexandre at 02:55 AM on 19 October 2011
       How Increasing Carbon Dioxide Heats The Ocean
       Harald Korneliussen at 22:10 PM on 18 October, 2011 There's an interesting series about this subject on ScienceOfDoom, beginning here: Does Back-Radiation “Heat” the Ocean? – Part One At some point into the series he explores some simple models to help understand the role of the upper turbulent layer you mentioned, that yes, also plays its role.
72356. Anne-Marie Blackburn at 02:44 AM on 19 October 2011
       How Increasing Carbon Dioxide Heats The Ocean
       Excellent post, Rob. Off to learn more about it.
72357. Albatross at 02:31 AM on 19 October 2011
       Continued Lower Atmosphere Warming
       Hello Dr. Pielke @77, "What I have reported on is the limited warming in the upper oceans in recent years (since 2004) which is clearly evident in http://oceans.pmel.noaa.gov/. If you (and the others) want to ignore the obvious you certainly can do that. " This is now getting very annoying Dr. Pielke. You may not realize it but you are making strawmen arguments. Also, I urge you (again) to please stop misrepresenting our position (this time on OHC) and going off topic. Anyone following our discussion with you knows that what you said above about us "ignoring the obvious" is simply not true. Additionally, you initially claimed on your blog that there has been zero accumulation of heat in the upper 700 m of the oceans since the beginning of 2003 (that error is still present on your blog for all to see), not "limited warming" since 2004. I am, sadly, beginning to have serious doubts that you are interesting in discussing the science in good faith.
72358. Philippe Chantreau at 02:29 AM on 19 October 2011
       OA not OK part 20: SUMMARY 2/2
       Funny how Watts uses a study that seems at first glance rather well done and then tries to argue for the opposite of what the study suggests. I note that he uses the term "weasel words" to qualify terminology used in the paper to communicate uncertainty. I wonder how Dr Pielke, for instance, would react to such vocabulary employed here. Funnily enough, "skeptics" have a habit of complaining that uncertainty is not plainly revealed in the litterature. Oh well. Compared to the recent Erl Happ fiasco, in which he was scolded by contributors for his gross igorance, and by Watts, for writing posts while drunk (and bragging about it), this one is rather tame. Voted best science blog, mind you.
72359. Dikran Marsupial at 02:11 AM on 19 October 2011
       Continued Lower Atmosphere Warming
       Eric (skeptic) I wouldn't agree or disagree, because without investigating the data I simply don't know. Fortunately there are methods for estimating the statistical power of a test, which can address such issues (although of course you also need to perform the test in collaboration with domain experts so you know what the issues are so the analysis is based on appropriate assumptions).
72360. Dikran Marsupial at 01:40 AM on 19 October 2011
       Continued Lower Atmosphere Warming
       pielkesr The problem with your revised statement is that it is incorrect to assert that one trend IS different from another unless the difference in trends is statistically significant. This is because the trend is a statistic that is only estimated from data, we don't know the true value of the trend, the best we can do is to compute a confidence interval that is indicative of the uncertainty of the estimate (loosely speaking if it is a frequentist confidence interval). So to assert that the trends actually are different you need to establish that the uncertainty in the estimation of the trends is sufficiently small that we can be confident that a difference actually exists. As for how long we need, the estimate of 17 years given by Santer et al sounds reasonable, and is consistent with other studies I have seen, though I haven't performed the calculation myself. In the case of your third hypothesis though, you only need to show that the difference is statistically significant, and don't need to consider the power of the test so much as you are arguing against the null hypothesis (the actual trends are the same). There is a complication due to the choice of the start point, but that is a finer point. We could perhaps agree that there was a difference in the estimated trends from 1979-2002 and 2002-2011, but that the difference was statistically insignificant, but that is a pretty bland statement and couldn't be used to support any statement about the climate.
72361. barry1487 at 01:29 AM on 19 October 2011
       How Increasing Carbon Dioxide Heats The Ocean
       Rob, thanks for this post. It's a bit of a missing link for lay people, I think. When you know that the average temperature of the ocean is warmer than that of the atmosphere, and that heat flows from a warmer body to a cooler one, the idea that a warming atmosphere can warm the oceans is not straightforwardly intuitive. You've clarified it well. Still have questions, though. When you say,

       "Indeed, climate models suggest that ocean warming will continue for at least a thousand years even if CO2 emissions were to completely stop."

       It makes me wonder why equilibrium is considered to be reached after 30 - 40 years of oceanic lag, rather than 1000. Why is the long tail not included in equilibrium climate sensitivity?
72362. Eric (skeptic) at 01:28 AM on 19 October 2011
       Continued Lower Atmosphere Warming
       Dikran, would you agree (or disagree) that the period required for statistical significance of a change in trend is shorter for ocean heat content than it is for GAT? IMO, it would be shorter for the reason that OHC is affected by fewer modes of natural variability than GAT, particularly the decadal ocean atmosphere cycles or quasi-cycles.
72363. pielkesr at 01:20 AM on 19 October 2011
       Continued Lower Atmosphere Warming
       Dikran Marsupial - Perhaps this will clarify, change "the trends during this time period [2002-present] are different than the trends earlier in the time period [1979-2002]." to "the 9 YEAR TREND during this time period [2002-present] IS different than the TREND FOR the time period [1979-2002]. THIS SHORT TERM TREND DIFFERENCE IS NOT LONG ENOUGH TO CONCLUDE THAT THE LONGER TERM TREND HAS BEEN CHANGED. HOWEVER, IT DOES PROVIDE US WITH A METRIC TO FOLLOW IN ORDER TO SEE HOW LONG THIS DIFFERENT TREND WOULD HAVE TO CONTINUE BEFORE WE CAN CONCLUDE THE LONGER TERM TREND HAS CHANGED IN TERMS OF STATISTICAL SIGNIFICANCE." Now, you are more of a statistics expert than I. Please tell us how many more years of the 2002 to 2011 trend would have to continue before one could conclude the long term trend has changed. This would be a diagnostic that both the SkS readers and the "skeptics" would agree on.
       Moderator Response: [Albatross] Please avoid using all CAPS. Thanks.
72364. adrian smits at 01:15 AM on 19 October 2011
       El Niño: Unaffected by climate change in the 21st century but its impacts may be more severe
       http://www.worldclimatereport.com/index.php/2011/10/17/no-change-in-storminess/ It would appear your press release has been trumped by peer reviewed scientific literature that has studied storm intensity over the last 5000 years with no indication of major change in storm intensity or quantity!
       Response:

       [DB] Actually, it would appear that your blog source inappropriately conflates:

       • a study of Holocene intense hurricane strikes in parts of the Gulf of Mexico (essentially local/regional conditions found during a time dissimilar to those expected during the 21st Century for the globe as a whole)
       • a study of extreme value statistics under modeled North Atlantic cyclones during winter conditions vs those in a warmer climate (again, a regional study; the primary finding was that in a warmer climate there was a more northern track followed by the cyclones; conclusions beyond that not possible due to the need for a larger sample size)

       So you would have readers here believe that a study looking at past, localized conditions in the Gulf of Mexico and another study of North Atlantic cyclone extreme value statistics (both with afore-detailed limitations) rule out future, global expected changes as detailed in the OP.  Seriously?

       A prudent "skeptic" would take the time to actually read the referenced studies for themselves before swallowing disinformation hook, line and sinker.

72365. Kevin C at 00:52 AM on 19 October 2011
       Lindzen Illusion #2: Lindzen vs. Hansen - the Sleek Veneer of the 1980s
       Oh yes, I see your point. (And I think you can also see how Charlie and I reached our conclusion?) Given the Lindzen's counterfactual picture of the temperature record, I guess Dana's line is as good as any. Sadly that's not a very satisfying criteria. I suppose presenting an ensemble of possible lines with Lindzen's gradient on the whole record might be more realistic, but that's ugly and arguably misleading too (and wouldn't fit on the graph for the new article). OK, I give up.
72366. Dikran Marsupial at 00:35 AM on 19 October 2011
       Continued Lower Atmosphere Warming
       Prof. Pielke I am somewhat reluctant to post on this topic again as you are merely repeating assertions that have already been addressed without further elaboration or justification. However I just want to make my position clear. I have already explicitly agreed with you on more than one occasion that the temperature trends in the UAH/RSS lower trophosphere datasets have not been significantly non-zero since 2002, and have been essentially flat. Indeed that is obvious. However, you have not established that this is meaningful, or even surprising. Such periods of little or no warming have occurred before in these datasets and undoubtedly will occurr again, they are also reproduced in model output (although for me this thread is largely about the observations rather than the models). As I have explained, the period is too short to be able to decide whether there has been a change in climate, or whether the flatness of the time-series is an artifact of natural variability. Both hypothesis remain plausible given the data from 2002-present, however there is no statistically significant evidence for a change in climate, and no physical reason has been suggested. So as far as I can see it is of little climatic relevance, but of great interest to those interested in the internal variability. It is interesting to refine our understanding of the redistribution of energy, but it says nothing about AGW. Now if you can demonstrate that there is statistically significant evidence for a change in the climate, or even just that the flatness of the trend is unusual or suprising, then you might generate some interest in your argument, but the onus is on you to demonstrate the evidence. Merely saying again and again that it is obvious is unconvincing when the statistical evidence tells a different story. The ball remains in your court.

       ---

       Just as a reminder, Prof. Pielke endorsed the folloing summary of scientific method: 1. Ask a Question 2. Do Background Research 3. Construct a Hypothesis 4. Test Your Hypothesis by Doing an Experiment 5. Analyze Your Data and Draw a Conclusion 6. Communicate Your Results" And he has explicitly stated an hypothesis "the trends during this time period [2002-present] are different than the trends earlier in the time period [1979-2002]." The periods in [] are inferred from the earlier content of that comment. However, as far as I can tell Prof. Pielke has not tested this hypothesis (other than to look at the data and claim that it is obvious), and has steadfastly refused to answer questions relating to statistical significance or the statistical power of the test. Thus he has not followed steps four or five in the summary of scientific method that he himself endorsed.
72367. victull at 00:34 AM on 19 October 2011
       Ocean Heat Poised To Come Back And Haunt Us?
       Jsquared @31 The planned deployment of 3000 Argo floats was reached in 2007 having started in 2001. 750 are released each year to maintain the system. I think a useful number for measurement of ocean heat was reached in 2004 - but would stand corrected on that date. The floats are nominally on a 300km spacing (presumably a 300km x 300km grid).
72368. Riccardo at 00:12 AM on 19 October 2011
       Continued Lower Atmosphere Warming
       Dr Pileke says "If you (and the others) want to ignore the obvious [...]" The obvious is not ignored, the point is what that means. It may be important for climate variability or for the warming trend. As apparently you agree that the short term trend is not statisticaly significant, I assume you're talking about variability, which is a completely different beast and as such it should be dealt with. and "I presume everyone will agree with is that from 2003 onward, the most appropriate diagnostic to monitor global warming is the ocean heat content changes." A lot of words has been said on the limitations of our knowledge of ocean heat content and that we need to consider many different metrics together. Why it should be otherwise is not clear to me.
72369. pielkesr at 23:47 PM on 18 October 2011
       Continued Lower Atmosphere Warming
       Bernard J. - You write "If Pielke Snr has the reference for the work that the planet has in fact not warmed since 1998 (or whenever) I would be most interested to read it." I have never said that. What I have reported on is the limited warming in the upper oceans in recent years (since 2004) which is clearly evident in http://oceans.pmel.noaa.gov/. If you (and the others) want to ignore the obvious you certainly can do that. Even Kevin Trenberth and Jim Hansen have not ignored this observation. The lower troposphere similarly has not warmed in recent years, nor has the lower stratosphere cooled. Stating the obvious should not be a source of disagreement. Your analogy to the ice baths is certainly unclear except I like your connection to heat (Joules) rather than temperature directly. What I presume everyone will agree with is that from 2003 onward, the most appropriate diagnostic to monitor global warming is the ocean heat content changes. If we can agree on that (and since you use the bath tub analogy which involves heat in Joules), than this thread and the others would have been time well spent debating. In terms of this thread, enough has been said. I will be posting my views on the experience on my weblog sometime this week.
72370. Paul D at 23:28 PM on 18 October 2011
       How Increasing Carbon Dioxide Heats The Ocean
       Logically wave energy should be small since it is third hand solar energy (Solar -> Wind -> Wave). Then you have the issue of how far it penetrates and causes any heating.
72371. Bob Lacatena at 23:12 PM on 18 October 2011
       Lindzen Illusion #2: Lindzen vs. Hansen - the Sleek Veneer of the 1980s
       Kevin, the text I find describing Lindzen's 1989 presentation goes on to say, after your quoted lines:

       He referred to MIT Professor Reginald Newell's work that suggests that between the 19th century and the present there appears to be no change in ocean surface temperatures. Moreover, the record for the 48 contiguous states shows no evidence for warming over the past century. "As far as the data goes, I would argue that we really don't have the basis for saying it's a half degree plus or minus 0.2. That is false use of science. What we have is data that says that maybe it occurs, but it's within the noise."

       Lindzen is clearly saying, here, that there has been no warming to speak of this century, and so his own baseline starts well below the actual warming we've seen, which is where Dana put it. It's Lindzen's prediction and Lindzen's interpretation of the observations that is being used. That Lindzen was so wildly in denial back in 1989 is his own fault and no one else's. Now some may consider this unfair, because Lindzen is being hit with a double whammy in his prediction, by both choosing a starting point far below reality (because he refused to believe there even was any warming) as well as choosing a climate sensitivity that precludes virtually any warming at all and in fact constrains everything within a very narrow range. So what Charlie A is really asking is that we excuse Lindzen's refusal in 1989 to accept the temperature record, and so now to let him hindcast himself back into reality... and then let his bad prediction go on from there, from a more accurate starting point (but one that was not a part of his very wrong 1989 view of the climate). As an aside, a discussion of Linzen's presentation from 1989 is a true Gish Gallop of unbelievable denial tripe. He was already laying the groundwork (a true climate pioneer!) of the denial arguments we see today. It's fun to see them in their early, less polished form. And it's overall pretty comical to read now, in 2011, knowing where things have gone, and what has and has not come to fruition since then.
72372. Rob Painting at 22:52 PM on 18 October 2011
       How Increasing Carbon Dioxide Heats The Ocean
       Harald - for sure mixing can vary significantly on short timescales - ocean temperatures would not be held constant in an "idealized" stable climate, they would still fluctuate, but without any long-term trend. The post only deals with one aspect of the ocean warming process, but perhaps the most important one, given the general confusion exhibited by some commenters on how the oceans warm. As for a series, I'll be covering some other aspects of the warming oceans, but have no intention of writing a series. Perhaps another SkS author might decide to do so, but I won't be holding my breath.
72373. DanaHicks at 22:15 PM on 18 October 2011
       El Niño: Unaffected by climate change in the 21st century but its impacts may be more severe
       Stevo, The following are ENSO plot for the past 130 years. The ENSO extremes have not changed during this timeframe. Oftentimes, it the timing of the ENSO events which have resulted in the extremes, rather than an extreme El Nino or La Nina. Link. Link. The followign shows the US record highs and lows for the past century. The oft-quoted trend is prdominantly a result of much fewer lows. The highs have also decreased, but not nearly as much as the lows. As skywatcher mentioned, warmer winters and nights, but there has been no noticeable change in high temperatures. Link. Link. Hope this helps.
       Moderator Response: [RH] Hot linked references to fix broken page formatting.
72374. Harald Korneliussen at 22:10 PM on 18 October 2011
       How Increasing Carbon Dioxide Heats The Ocean
       What about mixing from wave activity? Is it enough to matter? Does it vary significantly from year to year on a global scale? A series on this topic similar to your ocean salinization series, would be a great thing.
72375. Kevin C at 21:09 PM on 18 October 2011
       Lindzen Illusion #2: Lindzen vs. Hansen - the Sleek Veneer of the 1980s
       Well, I read the links to see if Charlie A was right in this thread or not. This paragraph seems to be the relevant:

       Nor, he said, was the temperature data collected in a very systematic and uniform way prior to 1880, so comparisons often begin with temperatures around 1880. "The trouble is that the earlier data suggest that one is starting at what probably was an anomalous minimum near 1880. The entire record would more likely be saying that the rise is 0.1 degree plus or minus 0.3 degree."

       If I read that correctly, Lindzen is claiming that the reason the ITR shows warming from 1880 is that 1880 was a local minima. 'The entire record' seems to refer to a fictitious but accurate temperature record going back rather further. His suggestion is therefore that the early 19th C temperatures were rather warmer, and that warming relative to the long term average is therefore rather smaller. My reading may be wrong, but it does look to me as though Charlie has a point: The reconstruction of Lindzen does not reflect what Lindzen is actually saying. Lindzen's claims may be confused and bizarre, they certainly contradict multiple sources of data, but I don't think he is claiming what the graph shows. (Sorry)
72376. Eric (skeptic) at 20:26 PM on 18 October 2011
       Continued Lower Atmosphere Warming
       ...this 'flattening' can be explained by increases in aerosol emissions, decreases in solar activity, and changes in ENSO (the former two of which are not 'natural variability,' but rather are forcings)... Dana, an even more precise description of those three examples is 1) a mostly anthropogenic, but partly natural (varying) forcing, 2) a naturally varying forcing in several modes and 3) a natural variation mostly resulting in ocean-atmosphere exchange but also some forcing. One could look at this paper ftp://128.95.176.42/pub/breth/CPT/cess_jcl01.pdf and conclude that cloud forcings from ENSO generally cancel so they can be disregarded. But the paper shows that over short periods they don't and that is what I and others would call a naturally varying forcing.
72377. Fran Barlow2 at 19:55 PM on 18 October 2011
       Correction to the True Cost of Coal Power - MMN11
       Basically, $50tCO2e gets you all the abatement that is cheaper than $50tCO2e. That's quite a bit, which is why a price on CO2e is a foundational measure and the cheapest way to do abatement. That of course isn't a measure of the true community cost of burning fossil HC, because as I said, the externalities go to much more than AGW. Really, we should err, if we must, on the high side. Let's make it clear that we are moving quickly to $100tCO2e (plus beyond if needed) and see what happens.
72378. adelady at 19:21 PM on 18 October 2011
       Ocean Heat Poised To Come Back And Haunt Us?
       alan - inconsistency is just a sign of immaturity. What does a three year old wear where they're allowed to dress themselves and choose whatever they want? They wear all their favourites. The rubber boots and the beach hat. The rainbow striped socks and the tartan pants. The party jacket over the pyjama top. No account of the obvious fact that there is no relationship of function, colour or pattern. They all look good on their own - so they all go on together. Bit like the intellectual and factual armoury of some rejectionists.
72379. GFW at 18:43 PM on 18 October 2011
       Correction to the True Cost of Coal Power - MMN11
       On the other hand, there'd be positive feedback (in the good sense) from a tax of say $50tCo2e. Because the price signal would affect consumption and push renewables into a very competitive position, many of the other costs associated with fossil fuels would go down (like the risks and costs of transporting the stuff long distances - local supplies would be used first, and be much closer to sufficient). I'm not saying that's the exact right price, but I think we could get to a safe sub-450 ppm peak without needing a price as high as Fran thinks. I'm far from an expert though.
72380. Bernard J. at 18:18 PM on 18 October 2011
       OA not OK part 20: SUMMARY 2/2
       To underscore my point above, Watts has (almost on cue) posted some dog-whistling nonsense that plays Dunning-Kruger bingo with every possible acid chemistry cannard - including the notion that a decrease of about half a pH unit over a century and a bit constitutes "a small change in ocean pH" to which "nature" should be able to adapt. It's enough to reduce to tears anyone with teritiary training in chemistry or biology...
72381. alan_marshall at 17:13 PM on 18 October 2011
       Ocean Heat Poised To Come Back And Haunt Us?
       Good post. The skeptics don’t understand that, like weather phenomena, the long term trend is modulated by shorter-term cycles. And deep ocean heat exchange isn’t the only one. There is also the modulation due to the average 11 year solar (sunspot) cycle – and we are presently at a solar minimum. It seems inconsistent that skeptics can maintain that the sun, rather than CO2, drives climate change, and yet when it suits them, maintain the climate is not changing by ignoring the modulation of the solar cycle. But then, consistency is only required if you want to follow the scientific method.
72382. Bernard J. at 15:31 PM on 18 October 2011
       Continued Lower Atmosphere Warming
       I find it bemusing that Pielke Snr can acknowledge that the post-1998 interval is too short an interval with which to determine (with statistical power) any trend, and then immediately - in the very same sentence, no less - claim that "the warming has halted". This is truly a bizarre stance, and one that implies the action of some sort of cognitive dissonance. Further, Pielke Snr seems to be confabulating planetary warming with perceived plateaux in planetary surface temperature*. The two are separate phenomena, correlated certainly, but not in lock-step. If Pielke Snr has the reference for the work that the planet has in fact not warmed since 1998 (or whenever) I would be most interested to read it. [* I perform a number of polar biology insulation experiments with my students that involve ice baths. These students understand that the ice baths are continuously warming as they sit on a bench, even as the temperature within the baths is not increasing...]
72383. Albatross at 15:11 PM on 18 October 2011
       Continued Lower Atmosphere Warming
       Dana @71, Re "Those who live in glass houses". I do not agree with that assessment of what is going on here as it suggests that SkS was indeed ridiculing Pielke. SkS was not doing so, in fact, John H. has said as much and I believe him. I will post more on that thread soon. As for these statements made by Dr. Pielke's post @69: "Your hypothesis that this is just part of the natural variability certain might be correct. It could also mean that the longer terms trend includes a larger natural component than you assume based on the model results. It could mean the other human climate forcings play a larger role than represented in the models. We need to explore each of these issues (and others) rather than being dogmatic and insist the models are faithfully replicating this aspect of the climate system. Also, "By ignoring the obvious (which is hardly "meaningless"), plays into the hands of those you call "skeptics"." It sadly seems that Dr. Pielke is intent on misrepresenting SkS's position, attributing to us positions that we do not hold and engaging in inflammatory rhetoric rather than objective science (e.g., "dogmatic"). Also, I fail to see how Dr. Pielke could have not seen the "flat" trend in the RSS data for 1998-present shown above. Note that the GISTEMP (NASA) surface data (land and ocean) for 1998-present shows a rate of warming of 0.11 C/decade for 1998-present (and we humans live near at the surface not the lower troposphere near 600 mb/14 000 ft). Although I have not tested the statistical significance of that particular trend-- it is still probably too short a period of time for which to derive a statistically significant trend, even for the GISTEMP data. But it does highlight again that one has to use a very particular dataset and for a very particular short-period of time to make the (very misleading) claim that the warming has 'halted'. Dr. Pielke has noted that we humans live on land and that "with respect to the global average surface temperature trend, the land portion makes up a significant portion of it". Well here is what has been happening at the land surface (from NASA)[we are aware of the limitations of the station data and Dr. Pielke has posted about that so there is no need to rehash them again here please]: [Source] Rather than SkS "ignoring the obvious" as Dr. Pielke falsely claims, I would argue that it is the "skeptics" (some who should know better) who are ignoring the obvious regarding the statistical relevance (and power) of their claims when they calculate trends for statistically insignificant periods of time and then make very definitive statements regarding the implications of that trend. Now while continuing arguing in circles may suite some who wish to create the impression that there is a debate, ignoring and dismissing inconvenient facts about statistical tests (and power) is not open for debate. There is a correct way to calculate a statistically meaningful and robust trends from noisy data. And to be quite candid, it was incorrect for Dr. Pielke to choose 1998, and worse yet 2002, as start dates for which to support the claim that "global warming has halted". There are no shades of gray on this. Had such a calculation and attendant claim that "global warming has halted", been been submitted for review in a reputable journal, that portion of the analysis and text would have received harsh criticism and the author/s would have been told to add a very clear caveat that the trend was not statistically significant, but far more likely they would have been instructed to remove the claim as it was not supported by the data in question.
72384. Stevo at 14:45 PM on 18 October 2011
       El Niño: Unaffected by climate change in the 21st century but its impacts may be more severe
       skywatcher, thanks for that. Am digesting Peterson et al 2008
72385. skywatcher at 14:10 PM on 18 October 2011
       El Niño: Unaffected by climate change in the 21st century but its impacts may be more severe
       I'm not sure I'm the one to try and answer that question. Certainly there seems to be trends in extremes, whether in the oft-quoted trend in US daily record highs over daily record lows, or in Peterson et al 2008. The temperature patterns are consistent with AGW as a cause, ie a rise in maxima, a rise in minima, and in many cases minima rising faster than maxima (along with winters warming faster than summer, nights faster than days) - see the relevant threads on human fingerprints of AGW.
72386. Stevo at 13:47 PM on 18 October 2011
       El Niño: Unaffected by climate change in the 21st century but its impacts may be more severe
       skywatcher, thankyou for your help. "A warmer atmosphere means that the ENSO extremes are made even more extreme, and relatively more records tuble as a result." Your disclaimer is also well noted. From what I've seen in recent years the extremes are certainly becoming more extreme. What are we looking for to be able to identify AGW as pushing these extremes? Is it a matter of waiting until our data of recorded events extend for long enough to be statistically valid?
72387. Tenney Naumer at 13:33 PM on 18 October 2011
       El Niño: Unaffected by climate change in the 21st century but its impacts may be more severe
       Reprint from 2011, not 2001.
       Moderator Response: [John Hartz]Thanks. Will correct.
72388. skywatcher at 13:20 PM on 18 October 2011
       El Niño: Unaffected by climate change in the 21st century but its impacts may be more severe
       Stevo, I think what you are missing is that a significant El Nino or La Nina represents a relatively extreme distribution of the energy in Earth's system. there's lots of heat in some places, less in others, some areas are particularly dry, others particularly wet. In a world with no warming trend, then extreme events related to heat, dry and wet might be expected to occur relatively more often when ENSO is at one particular end of its cycle, occasionally breaking records. Add in a warming trend, and the extreme events still occur quite often at the endpoints of ENSO, due to the (heterogeneous?) distribution of energy about the earth, conducive to local extremes of weather. However, the extra energy, heat, evaporation, precipitable water etc that is a physical product of a warmer atmosphere means that the ENSO extremes are made even more extreme, and relatively more records tumble as a result.* Not sure if that helps, but it's how I visualise it. For me, the increase in extremes are a product of global warming, but ENSO provides conditions in which you'll more likely see extremes. *disclaimer, I'm not saying all extremes are a consequence of ENSO, or all ENSOs produce large extremes.
72389. Stevo at 12:39 PM on 18 October 2011
       El Niño: Unaffected by climate change in the 21st century but its impacts may be more severe
       As has been demonstrated on other threads, the frequency and intensity of extreme weather events are on the rise and have been for 15 to 20 years. As some of you have pointed out to me the cause of many of these events can just as likely be sheeted home to ENSO as they can be to AGW. Can someone please help me out on this as I am getting a little confused? How can we explain the increase of extreme weather events if ENSO has not noticably intensified, but the extra water vapour and energy in the atmosphere due to warming can also be put down to effects of ENSO? Surely warming would be the culprit if ENSO is basically unchanged. What am I missing here?
72390. Bern at 11:56 AM on 18 October 2011
       Comparing Global Temperature Predictions
       Thanks for the article, Dana. And I love that animated GIF. Really tells the story. What would help, though, is to put that projected rise to 2100 in context - by, say, including the measured temps from 1900-2000 on the chart as well.
72391. skywatcher at 11:54 AM on 18 October 2011
       Continued Lower Atmosphere Warming
       Dr Pielke, I refer you back to my figure in #5. In 1985 (or 1994), or any of a number of low points in the record, could it honestly be said that "warming had halted", or that the trend was remotely likely to change, based on the available data? You lose a very great deal of credibility by concentrating on the noise rather than the signal.
72392. nealjking at 11:31 AM on 18 October 2011
       Continued Lower Atmosphere Warming
       Roger, You seem to be indulging in an abuse of terminology: - When you say, "The warming has halted," that implies that a warming trend has turned around. - But it has already been established quite clearly that no trend can be established over such short time intervals. So such a claim simply has no meaning. - By analogy, one doesn't claim that the local climate has gone into a local cooling period during the last quarter of the year: It's inappropriate to attempt to define a climate trend over such a short period.
72393. dana1981 at 11:29 AM on 18 October 2011
       Continued Lower Atmosphere Warming
       Dr. Pielke, several times we have noted that the TLT trend has been essentially flat over recent short periods (which are not statistically significant). We have also discussed that this 'flattening' can be explained by increases in aerosol emissions, decreases in solar activity, and changes in ENSO (the former two of which are not 'natural variability,' but rather are forcings). As for 'ridicule', this is not an activity SkS engages in. And those who live in glass houses should not throw stones.
72394. chrstoph at 10:48 AM on 18 October 2011
       Pielke Sr. and SkS Warming Estimates
       Well said @Rob Honeycutt, nicely distilled. Sometimes it's easy to miss the grain for all the chaff in the air. Was going to ask what the motivations were from Pielke Sr for arguing on such a point of contention - is it a need for correctness? It seems the motivations for SkS were summed up well by Rob HoneyCutt, though it seems in this thread they have been pretty nicely co-opted in creating more chaff for the doubters to point at (in my [admittedly] humble opinion).
72395. KR at 10:37 AM on 18 October 2011
       Continued Lower Atmosphere Warming
       Dr. Pielke - "Why not just state that you see this flatness in the data, but have concluded it is part of the natural variability as represented by the climate model predictions" With all due respect, that has been stated multiple times by multiple participants in this discussion, and in fact is a core conclusion of Santer et al. (2011), as linked and quoted in the opening post of this thread: "Because of the pronounced effect of interannual noise on decadal trends, a multi-model ensemble of anthropogenically-forced simulations displays many 10-year periods with little warming. A single decade of observational TLT data is therefore inadequate for identifying a slowly evolving anthropogenic warming signal. Our results show that temperature records of at least 17 years in length are required for identifying human effects on global-mean tropospheric temperature." (emphasis added) To be quite blunt, you are presenting a strawman argument by claiming that others do not recognize the effects of natural variability (they do, which is one of the major points of this discussion), and furthermore contradicting yourself when you "agree it is too short of a record" and then immediately claim "that the warming has halted". I find (IMO) this approach rather disingenuous.
72396. Jsquared at 10:14 AM on 18 October 2011
       Ocean Heat Poised To Come Back And Haunt Us?
       victull @29 Good question, but there's no way to tell without a lot more info than I have. There's no big change in the standard deviation in the data after about 2001, so whatever goes into that statistic (e.g., improved instrumentation) didn't change much. If they added a bunch of buoys in 2001, and that was it, there would have been a glitch at that point that went away the following year. If they kept adding a few buoys each year for several years, it might skew the data. But after the buoys are all planted, it should settle down again. So the question (to which I don't know the answer) is when they finished, not when they started.
72397. pielkesr at 09:33 AM on 18 October 2011
       Continued Lower Atmosphere Warming
       I see you have been busy commeting (and presenting q cartoon) while I was on travel and off of the internet. It seems SkS cannot get away without ridicule. :-) Nonetheless, in this first comment since my return, I want to make sure my perspective on the recent MSU lower tropospheric trends is clear. I keep getting asked in the comments why I do not complete a statistical evaluation of the data. The reason should be rather obvious but seems to still not be clear. So here it is. First, I am NOT saying anything about the effect of the lack of warming in the global-annual average surface temperature since 2002 or 1999 (or whatever start year) on the long term trend. I agree it is too short of a record. However, it is trivial in my view (and does not need any statistical evaluation) to see that the warming has halted, with this being clearly seen in the RSS Figure 7 in http://www.ssmi.com/msu/msu_data_description.html#channels. Whenever I show the RSS MSU data (including the lower stratospheric data which you have ingored in all of the comments), no one has raised the objection stating that the data is not ~flat in recent years. In my talks (and you soon will be able to hear the Waterloo talk if you chose) you will hear me highlight that this lack of warming does not tell us anything about the longer term trend. Your hypothesis that this is just part of the natural variability certain might be correct. It could also mean that the longer terms trend includes a larger natural component than you assume based on the model results. It could mean the other human climate forcings play a larger role than represented in the models. We need to explore each of these issues (and others) rather than being dogmatic and insist the models are faithfully replicating this aspect of the climate system. By ignoring the obvious (which is hardly "meaningless"), plays into the hands of those you call "skeptics". Why not just state that you see this flatness in the data, but have concluded it is part of the natural variability as represented by the climate model predictions. Then we can move on to other issues.
       Response:

       [DB] "I see you have been busy commeting (and presenting q cartoon) while I was on travel and off of the internet. It seems SkS cannot get away without ridicule. :-)"

       While it is appreciated that you partake of and enjoy the wide variety of threads available here at Skeptical Science it is recommended that you comment on the threads specific to the core of the above statement. 

       Thus, if you have a probelem with the subject matter of the cartoon in question, it is advised that you take that matter there instead of remonstrating about it here, where it is OT (indeed, please share with us - on the appropriate thread - just specifically how the cartoon in question is ridiculing anyone in specific).  After all, cartoons on blogs are hardly anything new...

       "...it is trivial in my view (and does not need any statistical evaluation) to see that the warming has halted, with this being clearly seen in the RSS Figure..."

       Again you repeat your mantra of the power of visual inspection in lieu of actual analysis.  In that case, I invite you to visually inspect the figures in this comment.

       As someone once said, "You do not need statistics to see the obvious."

72398. Dikran Marsupial at 09:11 AM on 18 October 2011
       El Niño: Unaffected by climate change in the 21st century but its impacts may be more severe
       tblakeslee Do not assume that just because a paper has appeared in a journal that it is correct. Be skeptical of all you read. First see if the paper has been cited, and by whom and where. If a paper has been in print for a while (or is one of a sequence of papers along the same lines) but nobody is citing it (other than self-citations) then there is probably a good reason for it. Second ask where it was published, was it published somewhere it would get a competent peer review. Look at the lines of evidence cited in the paper and see if they pan out, follow the references and see what they say. One should always be especialy skeptical of papers that are contraversial, big claims require big evidence. In this case, the paper cites the work of Friis-Christensen and Lassen (1991) on the link between solar-cycle length and northern hemisphere data. However, he doesn't cite the papers that show that the correllation was partially due to errors in the analysis and that as Lassen himself points out the correllation broke down soon after the Friss-Christensen paper was published. Now this was well known by the time Landscheidt wrote the paper, so you have to ask yourself (a) why he didn't mention this and (b) why the reviewers didn't pick it up if they were competent to review a paper on solar-climate links. The Friss-Christensen-Lassen paper is discussed here Secondly ISTR that you mentioned Landscheidt's work earlier and the statistical problems with his work were pointed out then, and yet you have not mentioned that caveat nor addressed them AFAICS. If you want to discuss this sort of solar-climate link, the thread concerned with the Friss-Christensen and Lassen paper would probably be more relevant.
72399. Robert Murphy at 09:11 AM on 18 October 2011
       El Niño: Unaffected by climate change in the 21st century but its impacts may be more severe
       tblakeslee, your links point to astrological theories about the movements of the planets causing solar cycles. Theodor Landscheidt for example had a book called "Sun, Earth, Man: A Mesh of Cosmic Oscillations - How Planets Regulate Solar Eruptions, Geomagnetic Storms, Conditions of Life and Economic Cycles". Those are the type of sources you think help your case? Really??
72400. KR at 09:09 AM on 18 October 2011
       Solar Cycle Length proves its the sun
       tblakeslee - In previous threads your hypothesis seemed to be that temperature was controlled by cosmic ray levels, not CO2. Now it's solar cycle length (Landscheidt) and momentum, not CO2? I hate to say it, but I'm seeing a certain lack of consistency here.

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