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Comments 72551 to 72600:

72551. Utahn at 05:08 AM on 15 October 2011
       Continued Lower Atmosphere Warming
       Sorry should say "similar to perhaps slightly slower pace than the long term trend when assessed from 2006 to now?" Long term trend meaning the past 30 years...
72552. Utahn at 04:59 AM on 15 October 2011
       Continued Lower Atmosphere Warming
       Dr. Pielke, you wrote, speaking of 2002 to present: "While it shows that lower tropospheric warming has essetially halted in the last few years (which we seem to agree on), it tells us nothing about the future, nor the reasons for the lack of warming." Will you agree to the statement that, while not telling us anything about the future, or the long term trend, that clearly lower tropospheric warming has essentially resumed at a similar or slightly faster pace than the long term trend from 2006 to now?
72553. Daniel Bailey at 04:58 AM on 15 October 2011
       Climate 'Skeptics' are like Galileo
       @ saltspringson 1. If by "suppression" you mean some scientists trying to keep bad papers from being published in quality journals without being improved to minimal standards of quality, then yes. 2. You'd better keep your money & invest it in actually learning more about climate science. Five years is a blink of an eye to overturn centuries of research by the lifetimes of thousands of scientists. The remainder of this point is a Gish Gallop on models & generic "skeptic" talking points (buzzwords like "Trenberth's missing heat" are a giveaway). 3. Actually, temps peaked due to climate system equilibria being reached several thousand years ago during the Holocene Climatic Optimum and then started a long, slow decline (marked by periods of natural variability) until the effects of mankind's injection of fossil-fuel GHGs into the carbon cycle began to take their toll. Temps now have equaled and begun to surpass those of the HCO (at a time when natural forcings should be pointed towards a continued decline to a glaciated state millennia in the future). Thus "skeptics" insisting that AGW has been overturned reveal themselves to be deniers of the science. 4. When it comes to the world is warming, that is settled fact. That mankind is 90% likely responsible for the majority of the rise post-1970 follows. That mainstream media, politicians and the public at large can be mislead by counter-disinformation campaigns funded by fossil-fuel interests intent on prosecuting an agenda of dissembling and anti-science is clear. I advise listening less to the dissembling bloggers & conspiracy theorists and learn for yourself what the science of climate change actually says for yourself.

       "Pour the coppers of your pockets into your mind and your mind will line your pockets with gold."

72554. Chris G at 04:44 AM on 15 October 2011
       Continued Lower Atmosphere Warming
       Darn my OS upgrade and loss of all allow-bookmarks-from-these-sites policy settings. Repeating: Dikrans point at (21) about the null hypothesis test has been unanswered. Dr. Pielke, Sr. (24) has requested a significance test when he and everyone else has agreed that it would have no meaning. What is the point of that? OHC versus TLT and police making: Granted, OHC is a stronger metric than surface temps, but we have very scant information on OHC and multitudinous and long records of surface temps. Why would anyone advocate ignoring the bulk of the information available when making policy? Focusing on OHC only plays into the hands of those that profit from policies which do not change BAU, because there is not yet a great deal of information about OHC. Re: "I suggest you, and others, hurt the environmental movement by focusing so heavily on just one environmental issue. " Whenever you have multiple problems and limited resources, you have to focus primarily on getting the best return on your investment. The vast majority of climate researchers are convinced that reductions of CO2 production improves our future situation more than any other factor. Maybe that is where we have recognise that there is disagreement between Dr Pielke, Sr. and a handful of others, and the majority, and move on.
72555. Albatross at 04:40 AM on 15 October 2011
       Continued Lower Atmosphere Warming
       Hello Dr. Pielke @19, You say: "While it shows that lower tropospheric warming has essetially halted in the last few years (which we seem to agree on), it tells us nothing about the future, nor the reasons for the lack of warming" And "This short term trend does not tell us that the long term trend has been significantly changed (yet)." I do not wish to be pedantic, but this is not what you told readers on your blog. You said: "they did not recognize that the global average temperature trend in the lower troposphere has been nearly flat as shown, for example, in the figure below from the RSS MSU data...There has been NO long-term trend since the large El Nino in 1998. That’s 13 years." You were quite assertive that this was a noteworthy finding and went so far to underline the '13 years'. And as for your claim "lower tropospheric warming has essentially halted in the last few years". "Halted" is very definitive, and is not consistent with your observation that "This short term trend does not tell us that the long term trend has been significantly changed (yet)". The fact remains that trends for 2002-present is simply too short a period to draw any meaningful conclusions, especially if one does not consider all the data and the role of aerosol loading, solar minimum, ENSO etc. It is also not an accurate characterization of what is happening. A more accurate way of describing it would be a temporary slow down, because we know from observations (e.g., Hansen et al. 2011) that the climate system is still in a positive energy imbalance and has continued to accumulate energy since 2002, albeit at a slower rate. Earlier@10 you also made the claim that: "What one sees in the defense of SkS of the long term linear trend is an effort to explain away differences that occur whenever they (unexpectedly) appear." and "The only remaining two options are the deep ocean and/or out into space. We should be focusing on this issue instead of how long a data set is needed to ferret out a slow linear trend." I take strong exception to those characterizations. It is the 'skeptics' who are trying to explain away AGW by focusing on the noise in the system and ferreting out out windows of time when there was little or no warming. Also, applying statistical analysis correctly as we are doing here is not "defending" anything except the intergity of the scientific method and appropriate statistical analysis. That is something that I would have hoped that you would endorse. To suggest that we, or IPCC scientists, are trying to "explain away differences" is simply not true. A great amount of time is spent by climate scientists looking at climate variability and working towards improving our understanding the climate system, I provided but a few links to the literature in my previous post @2. As I mentioned earlier, it is 'skeptics' who are trying to hide the incline and disappear the warming. I find it very odd that "skeptic" scientists do not use short-term trends to highlight periods of more rapid warming, why are such periods of warming any less important or of less scientific interest than hiatus periods? That they don't just highlights their confirmation bias. Doing that is very harmful because if fabricates debate, fosters doubt and misleads people into a false sense of security that the warming is not as bad as expected-- all based on statistically meaningless trends. As for your characterization of the "slow long term" trend is inaccurate in my opinion. That is a subjective and relative term and what people should correctly understand by 'slow' very much depends on the context. We are currently warming much faster than during the PETM, for example.
72556. Tom Dayton at 04:35 AM on 15 October 2011
       Continued Lower Atmosphere Warming
       Jonathon, unfortunately there is no "the" moving average. You must choose the timeframe for it--the surrounding two data years, or the surrounding four years, or.... And you're not examining just the moving average at a point, but the trend in the moving average over some number of years. How many years should you use? 2002 until now? 2008 until now? 1979 until now? How do you judge whether that trend is representative of the underlying population's trend (the "real" trend, in some sense)? You've got to apply a statistical test of some sort, but choosing that test requires attending to Dikran's explanations and cautions. Computing moving averages is one way to smooth out the noise so you can see the signal, but it is not magic. There still is noise, so you still need to examine the trend over a long enough time to have the statistical power to detect the signal over that noise.
72557. Dikran Marsupial at 03:49 AM on 15 October 2011
       Continued Lower Atmosphere Warming
       Prof. Pielke wrote: "Regarding #21, we will just have to disagree and move on." No, I'm sorry Prof. Pielke but you cannot simply ignore correct statistical practice, it is a cornerstone of modern scientific method. If you cannnot demonstrate that an hypothesis is supported by the data then you should not use it as a basis for your arguments. If you continue to make such arguments there is a strong possibility that you will be misleading those who are listening to them. "You are asking if the recent data alters a longer term trend significantly. I ageee; it does not." So you would agree that your third hypothesis is not supported by the data then? If so, that is good, but one wonders in that case why you put the hypothesis forward? "But what I am asking is if you took the data since 2002, does it show a trend that is significantly different than zero." I have already said (here) that I agree that your first hypothesis is undoubtedly correct. However I have also pointed out at least three times that unless the hypothesis test has useful statistical power the fact that the trend is not significantly different from zero is essentially meaningless. You have made no attempt to address that issue whatsoever. Now I have asked you three times to state the statistical power of the test and have not recieved a direct answer on any of these occasions. This is not unreasonable question to ask a senior academic in a field that deals with the analysis of observational data, the proper interpretation of a statistical hypothesis test is something that every scientist should feel comfortable with. There is no point in asking again, so I won't, but will instead have to conclude that you are either unable or unwilling to answer the question. I find that rather troubling.
72558. Albatross at 03:48 AM on 15 October 2011
       Continued Lower Atmosphere Warming
       Hello Dr. Pielke, With all respect, you are going off topic and obfuscating. Normally off topic posts are deleted. This thread was written to address the choice (by you) of 1998 as a start date with which to calculate a short-term trend and then confidently assigning importance to the resulting trend. You now seem to have shifted your focus to 2002, but this all started with the curious choice of 1998. Trying to shift focus to 2002 looks to me like implicit acceptance by you that 1998 was not an appropriate start date for calculating a short-term trend. We have discussed OHC with you before, and readers will recall we agree with you and Hansen that OHC is an important metric (one of several), we have been very clear on this, so please don't try and suggest otherwise. SkepticalScience has numerous threads that speak to OHC and energy in the climate system. See here and here. But that is not what is at issue on this thread, so if you wish to discuss OHC please do so on the relevant thread or at our ongoing discussion about OHC here. Thank you. And Dikran's questions (and points) are actually very relevant to the topic of this thread and their implications are important, so I for one encourage you to look at the statistical power of your hypothesis tests for the stated time frames and to please let us know what you find. Thanks.
72559. Jonathon at 03:43 AM on 15 October 2011
       Continued Lower Atmosphere Warming
       Instead of selecting an arbitrary timeframe, which lends itself to statistical errors, why not examine the moving average. This eliminates the subjective error in the analysis. Using HadCRU monthly values (other datasets produce similar numbers), the 120-month moving average was generally increasing over the following timeframes: 1896-1903, 1914-1946,1957-1967, and 1979-2008. During the other timeframes it was decreasing: 1887-1896, 1903-1914, 1946-1957, 1967-1979, and 2008-present. Since the moving average had been increasing since 1979, it is not surprising than any start date chosen for analysis since then would show a positive slope. The moving average has only been decreasing for three years, so only a short timeframe would show a temperature decrease.
72560. pielkesr at 03:32 AM on 15 October 2011
       Continued Lower Atmosphere Warming
       dana1981 - You write "There are a lot of people who are looking for excuses not to take action on climate change, and they will gladly latch onto your "no warming since 1998" argument whilst ignoring your "we should focus on OHC" argument (Anthony Watts being one of them). Your strategy here gives the delayers the ammunition they need." Unfortunately, what you assume is a perspective of "climate change" that is a much narrower view than I and many of my colleagues have concluded. Moreover, you focus on "climate change" when the focus should be on "climate", including risks we face if past extreme events reoccur but with today's societal exposure. We discuss this approach in our paper Pielke Sr., R.A., R. Wilby, D. Niyogi, F. Hossain, K. Dairuku, J. Adegoke, G. Kallos, T. Seastedt, and K. Suding, 2011: Dealing with complexity and extreme events using a bottom-up, resource-based vulnerability perspective. AGU Monograph on Complexity and Extreme Events in Geosciences, in press. http://pielkeclimatesci.files.wordpress.com/2011/05/r-365.pdf Anthony Watts, and others, do not conclude there is no human role in the climate system, nor that we should not do things that are environmentally positive. You misstate this information. The disagreement, and I share this, is that the focus almost exclusively on added CO2 by itself, could prevent other important issues from being addressed. It also makes geoengineering, such as the dangerour idea of ejecting aerosols into the stratosphere, a proposed approach to mitigate the radiative effect of added CO2. This why the failure to accept a slowing down of the tropospheric warming, which seems so obvious to me, actually prevents a more constructive discussion with the so-called "skeptics". I suggest you, and others, hurt the environmental movement by focusing so heavily on just one environmental issue.
72561. WheelsOC at 03:30 AM on 15 October 2011
       Continued Lower Atmosphere Warming
       Dr. Pielke, I'm reading your comments on Santer et al. and here to the best of my abilities but I haven't yet seen an explanation for your use of short time scales in response to a paper that was explicit in calling this approach wrong-headed for easily understood statistical reasons. If using >17 years is insufficient to draw conclusions about the agreement between models and observations, why do you think it's appropriate to do exactly that? I also don't see an explanation for your use of RSS over UAH data when Santer et al. used both (RSS happens to give a flat slope for the same time period that UAH gives a positive one), and your explanation of picking 1998 as the starting point in a type of analysis which is well known to be sensitive to end-point selection is also unsatisfactory, especially in light of the short-term variability creating noise that makes it difficult to tease out all but the strongest trends into statistical significance. Yes, 1998 as a start makes a "flat" trend, but any year prior and several years after 1998 produce a positive trend. Could it be that this apparently flat trend is entirely a relic of 1998's status as an unusually warm year, and therefore an illusory trend that's not worth bothering with? To me, these are the main points of contention here and you are apparently not addressing them. It's especially disheartening because these exact same methods (selective use of end points, short time scales, and focusing only on data that produce low or no trends) have been abused extensively by people who argue that there's no anthropogenic warming, something I know you disagree with.
72562. muoncounter at 03:26 AM on 15 October 2011
       There is no consensus
       Jonathan, 'General agreement' was exactly how I defined consensus. You have added 'we all agree,' which requires unanimous consent - a goalpost shift if ever there was one. I doubt you will ever find that.
72563. pielkesr at 03:22 AM on 15 October 2011
       Continued Lower Atmosphere Warming
       dana1981 You wrote "However, we all agree that global warming is not measured only by TLT and upper ocean data." It is measured by all the reservoirs of heat in the climate system and is in units of Joules. The dominate resevoir is the ocean. Do you agree with this?
72564. pielkesr at 03:21 AM on 15 October 2011
       Continued Lower Atmosphere Warming
       Dikran Marsupial - Regarding #21, we will just have to disagree and move on. You are asking if the recent data alters a longer term trend significantly. I ageee; it does not. But what I am asking is if you took the data since 2002, does it show a trend that is significantly different than zero. To say the tropospheric heating has not been less in recent years, is like saying a car is still accelerating with the speedometer says it is at a nearly constant speed over the last few kilometers. But lets move to the next topic.
72565. dana1981 at 03:13 AM on 15 October 2011
       Pielke Sr. and SkS Disagreements and Open Questions
       Dr. Pielke:

       "to some, this does raise an issue with the claims of the dominance of the radiative effect of CO2 and a few other greenhouse gases in terms of climate change"

       Those "some" are wrong, and thus we seek to explain why they are wrong. We are trying to "refute the use of the shorter term temperature trend data" because forming conclusions based on short-term data is inappropriate. Yes, we are trying to refute something that is incorrect, and will continue to do so. However, TLT discussions should move to the TLT thread, and we should be moving on to the OHC point #3 in this thread. See the second link in my comment #110 for the latest on point #3.
72566. Jsquared at 02:58 AM on 15 October 2011
       The Earth continues to build up heat
       @JosHag Thanks. The Levitus 2000m time series at nodc.noaa.gov (mentioned in #7) doesn't have the error column. The file h22-w0-2000m.dat does (3rd column). And there are two of those graphs over at RealClimate - one wittout the error bars (mentioned in #7) and one with (mentioned in #24).
72567. dana1981 at 02:48 AM on 15 October 2011
       Continued Lower Atmosphere Warming
       Dr. Pielke, you say

       "Since 2002, as shown in the lower tropospheric plot and in the upper ocean data, little of that heat has accumulated there. There is not enough melt of sea ice or glaciers to account for it there. "Global warming" has nearly stopped using these two metrics, irrepsective of the long term trend and whether it is due to natural variations or an incomplete understanding of human climate forcings."

       However, we all agree that global warming is not measured only by TLT and upper ocean data.

       "What one sees in the defense of SkS of the long term linear trend is an effort to explain away differences that occur whenever they (unexpectedly) appear. This may provide encouragement for the convinced but, I suspect, is making a large number of others (e.g. including policymakers) suspicious of the claims."

       A main point of Santer et al. is that these short-term deviations from the long-term trend are not unexpected, and thus I strongly disgree with your characterization of our post. What I think makes policymakers suspicious are arguments like yours, when they are told that the lower atmosphere hasn't warmed since 1998 or 2002.

       "My recommendation is, that instead of spending the effort to show that 2002 to 2011 (or 1999 to 2011) is too short of a time to necessarily see the linear trned, if it is there, that you focus on reporting on the observed data without a pre-chosen view that you are trying to defend."

       Our "pre-chosen view" is simply that we must examine all available climate data, and not selectively omit certain pieces of it (like TLT temperatures prior to 2002 or 1998, or the entire UAH record, for example).

       "I agree with almost all of your comments about the issue with the use of short term trends. While it shows that lower tropospheric warming has essetially halted in the last few years (which we seem to agree on), it tells us nothing about the future, nor the reasons for the lack of warming. "

       I would agree that the trend in the short-term, very noisy TLT data has slowed the past few years (though Dikran, who has much more statistics expertise than me, might smack me for saying so), but this is not an unexpected result (and I would go so far as to call it an expected result, given changes in ENSO, aerosols, and solar activity over that period), and certainly agree this tells us nothing about the future.

       "Lets also agree, however, to focus on the actual best measure of global warming - the oceans."

       On this we don't agree, and I think your pursuit of this goal is doing much more harm than good. In order to convince others that we should focus on OHC, you have also made this argument that TLT has not increased since 1998 or 2002. There are a lot of people who are looking for excuses not to take action on climate change, and they will gladly latch onto your "no warming since 1998" argument whilst ignoring your "we should focus on OHC" argument (Anthony Watts being one of them). Your strategy here gives the delayers the ammunition they need. As we have said many many times, OHC is a very important metric, but there should not be a single metric. We should examine all metrics, including OHC, TLT, surface temps, ice mass, etc. And as noted above, my main concern is providing ammunition for those who seek to undermine any and all action to address climate change, which is what your argument here does. I suggest you re-evaluate your messaging strategy, because it is currently doing more harm than good.
72568. MA Rodger at 02:47 AM on 15 October 2011
       Pielke Sr. and SkS Warming Estimates
       @89 Pielke Sr listed forcings as being (i) direct radiative, (ii) indirect radiative & (iii) non-radiative giving examples of the second sort in the reference. I see no relevance in such distictions within the presented argument. AR4, NAP and Tom@37 all refer to changes in forcing (of whatever ilk). Where I lose the thread in @89 starts with the talk of "mixing" which I am not clear even whether to read as some philisophical or some climatical mixing. My confusion continues with the second from last sentence which appears to be missing some words and the final sentence is devoid of any mention of "immediate" forcing or the logic for a forcing not being a relative phenomenon. In all these replies, the nearest thing to an explanation is @42 where Pielke Sr states "ΔF is the change in forcing ... that does require a base year. The forcing does not and is instantaneous. One would never state that "acceleration requires a base time period." Acceleration is the derivative of the velocity at any time. Similarly, radiative forcing is at a specific time although one could time average (e.g. the yearly global averaged radiative forcing)." This is however muddled thinking. Acceleration represents a rate of change in velocity, velocity a rate of change in distance. Here we consider 'forcing' and 'change in forcing' not a rate of change. There must then surely be a datum to measure from.
72569. Alexandre at 02:38 AM on 15 October 2011
       Continued Lower Atmosphere Warming
       muoncounter at 14:02 PM on 14 October, 2011 A smoker friend of mine is proud of kowing everything about quitting smoking: he says he has quit over 50 times... Likewise, global warming ends almost every other year... then it ends again. And again.
72570. Dikran Marsupial at 02:37 AM on 15 October 2011
       Continued Lower Atmosphere Warming
       Prof. Pielke wrote "I agree with almost all of your comments about the issue with the use of short term trends. While it shows that lower tropospheric warming has essetially halted in the last few years (which we seem to agree on)" No, it shows nothing of the sort. The failure to reject the null hypothesis (flat trend) does not imply that the trend actually is flat, that is a classic misinterpretation of a statistical hypothesis test. If the the null hypothesis is not rejected, there are essentially two reasons why this can happen. The first is that the null hypothesis is correct. The second is that the period over which the trend is calculated is too short to reliably estimate a trend of the expected magnitude. To rule out the second possibility, you need to show that the test has sufficient statistical power to reliably reject the null hypothesis if it is false. You have yet to demonstrate this, and so you should not be claiming that "lower tropospheric warming has essetially halted in the last few years". So, I ask again, what is the statistical power of the test?
72571. Jonathon at 02:26 AM on 15 October 2011
       There is no consensus
       Muon, See posts #475, #470, #456, and #454 for your answer. Remember, it was the other posts here at SKS who came up with claims, not myself. You would also be wise to learn that Webster defines consensus as "general agreement." If posters here are defining consensus as something else, then that would be reason for confusion.
72572. Eric (skeptic) at 02:21 AM on 15 October 2011
       Continued Lower Atmosphere Warming
       Muoncounter, the real sidetrack is OHC. But regardless the unshakeable trend is 0.4 over 30 years (UAH). There's also a somewhat shakeable change in trend from 80's and 90's to the 00's although it's still clearly up. I would also note that 35 years places the starting point into the cooler 70's.
72573. pielkesr at 02:16 AM on 15 October 2011
       Continued Lower Atmosphere Warming
       In terms of how we separately view the global warming issue, we clearly differ in a fundamental perspective. I have concluded that the appropriate way to monitor multi-year (multi-decadal) global annual-average warming (or cooling) is in terms of heat accumulation in Joules, which is by far dominated by the oceans. Even Jim Hansen has agreed with this view. Here is one example of its value. If, for example, a large volcanic eruption caused a large loss of Joules, the global warming "clock" would be reset. In contrast, the use of a linear trend would see this cooling as a short term blip and the positive linear trend would be retained until (and unless) the cooler heat content persisted long enough. I have used the muted (lack) heating in the troposphere since 2002 to reinforce that we need to focus on the ocean. I agree with almost all of your comments about the issue with the use of short term trends. While it shows that lower tropospheric warming has essetially halted in the last few years (which we seem to agree on), it tells us nothing about the future, nor the reasons for the lack of warming. However, by not focusing on the ocean heat content issues, including the reported heating in the deeper ocean including how it got there, you are missing an opportunity to reach out to those you call (perjoratively in my view although some like this label) "climate skeptics". Lets agree that it is a short term flattening in the lower tropospheric temperatures (since 2002) that we will all follow to see if it persists in the coming months and years. This short term trend does not tell us that the long term trend has been significantly changed (yet). Lets also agree, however, to focus on the actual best measure of global warming - the oceans.
72574. JosHagelaars at 02:01 AM on 15 October 2011
       The Earth continues to build up heat
       @Jsquared You can find the original graph with the error bars from comment #3 on: http://www.realclimate.org/index.php/archives/2011/10/global-warming-and-ocean-heat-content/comment-page-3/#comment-216587 I don't think the graph is taken from an article but is probably build by Schmidt himself, he links in his comment to: ftp://ftp.nodc.noaa.gov/pub/data.nodc/woa/DATA_ANALYSIS/3M_HEAT_CONTENT/DATA/basin/yearly/ The monthly data are here: ftp://ftp.nodc.noaa.gov/pub/data.nodc/woa/DATA_ANALYSIS/3M_HEAT_CONTENT/DATA/basin/3month/ Also see my comment #7
72575. muoncounter at 01:58 AM on 15 October 2011
       There is no consensus
       Jonathan#478: Once again, this is not the thread for detailed sensitivity discussion. By disagreeing with 'claim number one,' are you suggesting that sensitivity is either 0 or negative? If so, you would do well to refer to a sensitivity thread. But you have created new goalposts in the other two of your three claims: 'we all agree.' There is no such specific language in the definition of consensus as 'general agreement.' This is similar to the artifice used by the petition project, which contrived this language: there is no convincing scientific evidence that human release of carbon dioxide will, in the forseeable future, cause catastrophic heating of the Earth's atmosphere" Such language as 'convincing,' 'forseeable,' and 'catastrophic' are non-scientific. And 'we all agree' is higher than most legal burdens of proof.
72576. muoncounter at 01:41 AM on 15 October 2011
       Continued Lower Atmosphere Warming
       Eric#15: Volcanoes and ENSO each have their own threads; let's not get sidetracked here. If the natural cycles counter-argument is to be taken seriously, these factors must be quantitatively removed from the temperature record, as tamino did; we have repeatedly posted the resulting graph (above Figure 4). The result of that analysis is the familiar 35 year trend of 0.18 deg C per decade, which seems unshakeable at this point.
72577. jyyh at 01:23 AM on 15 October 2011
       Continued Lower Atmosphere Warming
       #5 Skywatcher, selecting the years on shorter period trendlines so they begin when the solar cycle is rising to the max about 1/3 from the top (2-3 years before the actual maximum (sunspots)). Can't find the image now (possibly lost somewhere in Tamino archives), but that was the idea, to tease out the maximum effect of the sun in current conditions of GHGs. Needless to say, selecting the years the opposite way gives increasingly steepening trendlines.
72578. JMurphy at 00:53 AM on 15 October 2011
       Over 31,000 scientists signed the OISM Petition Project
       Tristan wrote : "The IPCC AR4 WG1 report was written and reviewed by approximately 2000 scientists." - needs a link... I haven't counted all the names in Annexes II and III : Contributors and Reviewers of the IPCC WGI Fourth Assessment Report, but there can't be too far off 2000 names there, can there ? Anyone care to count...?
72579. Don9000 at 00:46 AM on 15 October 2011
       Continued Lower Atmosphere Warming
       Prof. Pielke @10: I do not understand why you write with regard to Dana's piece that "It amazes me that with the diversity of human climate forcings, the newly recognized higher importance of solar forcing, of internal variations and other effects, that you persist in assuming that the slow forcing of added CO2 will dominate if we integrate over enough years. Perhaps you are right, but you will not be convincing unless, in my view, you adopt a different tact." Dana's key opening point was that skeptics are and have been using short runs of temperature data to claim that global warming has stopped or reversed. This point was illustrated by Dana and others who posted graphs illustrating just how easy it is to select a short run of years and show that for those short stretches of time the trend is negative, while over a slightly longer time frame the trend is positive. As brief trends are often reversed in the wider trend once a statistically suitable longer span of years is considered (17 years, according to Santer et al (2011), being the minimum required for statistical significance), and once we look at such a span of recent years the global temperature is seen to be rising, it seems to me your attempt to argue that short term trends are of more interest than the overall longer-term trend is flawed. Incidentally, the word you should have used in calling for Dana to change his course of inquiry is "tack" and not "tact": "tack" is a nautical term which has to do with a vessel's course or direction of movement and is of particular importance to sailing ships. A sailing ship crossing the Atlantic, for example, might tack many dozens of times in order to maximize its use of wind energy or to avoid storms and areas of calm winds. When plotted on a map, individual tacks (the term can describe the run of the ship along a particular short-term course) may well make it appear that a ship heading from Liverpool to New York is heading for either Greenland or South America or even at times back toward Europe, but extended over time the various tacks produce a directional trend that causes the ship to arrive at its intended destination. Metaphorically, it seems to me that you are trying to argue that an individual "tack" takes precedence over the overall course and that we do not know which overall course the global temperature is on.
72580. Jonathon at 00:33 AM on 15 October 2011
       There is no consensus
       Sphaerica, You are a little late to the party, so I will bring you up to date. 1. The claim has been made here that since atmospheric CO2 leads to increasing temperature that there is a consensus on climate sensitivity, and it is positive. 2. The claim has also been made that the actual range which makes up the climate sensitivity is irrelevant, as long as we all agree on the endpoints of that range. 3. The final claim is that we all agree on that range. I disagree with all three claims. The first two claims are simply ridiculous, as they have no real meaning. It is not enough to know that X influences Y, but we need to know how much X influence Y, and if the influence of X on Y is unlimited, then do we really know anything about X and Y? The third claim is the only one with any real meaning. It is not sufficient for a small group to agree on a range if others do not, and calling Link, Spencer, Pagani, and Hansen "fringe scientists" does not add to your credibility. If you wish to add anything further, I suggest you tone down your attitude and try to become scientific in this discussion.
       Response:

       [DB] "If you wish to add anything further, I suggest you tone down your attitude and try to become scientific in this discussion."

       Good advice; please embody it yourself so others may emulate your positive example.

72581. Eric (skeptic) at 23:57 PM on 14 October 2011
       Continued Lower Atmosphere Warming
       Muoncounter, you ask: "Where are those explanations in more depth than 'it's a natural cycle'?" There are two effects from natural cycles. First is ocean-atmosphere exchange, second is radiative balance changes from volcanoes, ENSO-induced clouds, etc. The most in-depth explanation would consider both simultaneously and show heat accumulating at varying rates. The rate, generally speaking, was higher in the 80's and 90's and lower but still positive in the past decade.
72582. Dikran Marsupial at 23:46 PM on 14 October 2011
       Continued Lower Atmosphere Warming
       Prof. Pielke wrote: "I assume you mean pre-2002 and 2002-2011. What is it?" Yes, that appeared to be your third hypothesis, the 2002 breakpoint was inferred from the reference to the other two hypotheses. Have you tested your third hypothesis to see whether it has statistically significant support from the data?
72583. muoncounter at 23:45 PM on 14 October 2011
       Continued Lower Atmosphere Warming
       pielkesr#10: "one sees in the defense of SkS of the long term linear trend is an effort to explain away differences that occur whenever they (unexpectedly) appear. " This philosophical argument cuts both ways. As warming continues, those who say 'warming stopped in ___ ' are also left to explain those differences. Where are those explanations in more depth than 'its a natural cycle'? "instead of spending the effort to show that 2002 to 2011 (or 1999 to 2011) is too short of a time to necessarily see the linear trned, if it is there, that you focus on reporting on the observed data without a pre-chosen view" Again, a question that must be asked on both sides. How is using the entire satellite dataset a pre-chosen view? How is choosing an arbitrary short time period not a pre-chosen view? What I find missing here is internal logical consistency. If trends from 5 year periods are considered significant, then any 5 year period is as good as any other -- and that must include the most recent. As far as effort is concerned, it is far more effort to explain these short period variations than to address the significance of the long term trend.
72584. Robert Murphy at 23:39 PM on 14 October 2011
       Continued Lower Atmosphere Warming
       One way to look at the temperature record is to look at how adding the years after 1998 affects the long term linear trends. I made a graph from WoodForTrees of the 4 main data sets, starting in 1979 (so I could use the entire satellite record), and comparing the trends from 1979 thru the end of 1998 with 1979 thru the present (I made the graph about a month ago so it isn't updated for the most recent months). For GISS and UAH, the trend actually got a little larger when the last 13 years are added; the trend just barely decreased for RSS and HadCrut. Overall it doesn't look like adding the "flat" years made much of an impact on the long term trend, which you would think would be the case if the warming ended in 1998.
72585. pielkesr at 23:32 PM on 14 October 2011
       Pielke Sr. and SkS Disagreements and Open Questions
       JMurphy - You write "But who do you (Dr Pielke) believe is doing the misleading" I do not subscribe to the thesis that anyone is deliberating misleading. Everyone I know on all sides of this issue are sincere in their views. This, of course, does not make them correct, but I suggest starting with that respect will go along way to determining what is agreed to and what is not agreed. Then find mutually agreed to ways to resolve the disagrements, or at least to clearly articulate them. I know SkS's goal is to do this. However, in my experience on SkS, as one example, you are seeking to refute the use of the shorter term temperature trend data, rather than accepting that to some, this does raise an issue with the claims of the dominance of the radiative effect of CO2 and a few other greenhouse gases in terms of climate change.
72586. pielkesr at 23:26 PM on 14 October 2011
       Pielke Sr. and SkS Disagreements and Open Questions
       Tom Curtis - If I look at the RSS MSU plot since 2002, it looks flat over the period 2002-2011. I do not know what it will be in 2012 and 2013. What is your expectation for the next, say, 5 years?
72587. pielkesr at 23:20 PM on 14 October 2011
       Continued Lower Atmosphere Warming
       Dikran Marsupial My question is: Is the difference in the trend prior to 2002 and post-2002 statistically significant at the usual 95% level of significance? I assume you mean pre-2002 and 2002-2011. What is it?
72588. pielkesr at 23:18 PM on 14 October 2011
       Continued Lower Atmosphere Warming
       dana1981 - In your analysis you miss, in my view, a fundamental issue. Jim Hansen has written "The Willis et al. measured heat storage of 0.62 W/m2 refers to the decadal mean for the upper 750 m of the ocean. Our simulated 1993-2003 heat storage rate was 0.6 W/m2 in the upper 750 m of the ocean. The decadal mean planetary energy imbalance, 0.75 W/m2, includes heat storage in the deeper ocean and energy used to melt ice and warm the air and land. 0.85 W/m2 is the imbalance at the end of the decade. Certainly the energy imbalance is less in earlier years, even negative, especially in years following large volcanic eruptions. Our analysis focused on the past decade because: (1) this is the period when it was predicted that, in the absence of a large volcanic eruption, the increasing greenhouse effect would cause the planetary energy imbalance and ocean heat storage to rise above the level of natural variability (Hansen et al., 1997), and (2) improved ocean temperature measurements and precise satellite altimetry yield an uncertainty in the ocean heat storage, ~15% of the observed value, smaller than that of earlier times when unsampled regions of the ocean created larger uncertainty." [http://pielkeclimatesci.files.wordpress.com/2009/09/1116592hansen.pdf] A rate of heating of 0.85 Watts per meter squared corresponds to 1.38 x 10^22 Joules per year. This a metric than can be evaluated on a yearly basis (with uncertainties) and tracked with time. Since 2002, as shown in the lower tropospheric plot and in the upper ocean data, little of that heat has accumulated there. There is not enough melt of sea ice or glaciers to account for it there. "Global warming" has nearly stopped using these two metrics, irrepsective of the long term trend and whether it is due to natural variations or an incomplete understanding of human climate forcings. The only remaining two options are the deep ocean and/or out into space. We should be focusing on this issue instead of how long a data set is needed to ferret out a slow linear trend. One other comment; you report "Tamino has also previously performed a multiple regression of temperature on various short-term effects, including the Multivariate ENSO Index (MEI), and confirms that TLT data are much more sensitive to ENSO than surface temperature data". However, as reported in CCSP 1.1, the surface and lower tropospheric temperature trends are supposed to be closely linked in terms of trends. [ http://www.climatescience.gov/Library/sap/sap1-1/finalreport/default.htm]. What one sees in the defense of SkS of the long term linear trend is an effort to explain away differences that occur whenever they (unexpectedly) appear. This may provide encouragement for the convinced but, I suspect, is making a large number of others (e.g. including policymakers) suspicious of the claims. Examples of the unanticipated (as illustrated by Jim Hansen's statement) include reported deep ocean heating as a source of the "missing heat", the disparity between trends in the lower troposphere and the oceans, and need to adjust the data to account for ENSO, etc. And yes, the absence of much of a trend since 2002 fits into the conclusion that the linear trend oversimplifies the actual behavior of the climate system. My recommendation is, that instead of spending the effort to show that 2002 to 2011 (or 1999 to 2011) is too short of a time to necessarily see the linear trned, if it is there, that you focus on reporting on the observed data without a pre-chosen view that you are trying to defend. It amazes me that with the diversity of human climate forcings, the newly recognized higher importance of solar forcing, of internal variations and other effects, that you persist in assuming that the slow forcing of added CO2 will dominate if we integrate over enough years. Perhaps you are right, but you will not be convincing unless, in my view, you adopt a different tact. That tact, I suggest, is to focus that too large of an increase of the atmospheric concentration of CO2 as unknown as we do not know its consequences in terms of biogeochemistry. A prudent behavoir would be to encourage limiting how much we put into the atmosphere. As an associated effect, its positive radiative forcing would be less.
72589. Bob Lacatena at 23:17 PM on 14 October 2011
       There is no consensus
       475, Jonathan, Your entire rant is simply muddying the waters of what a definition of consensus might mean. As has already been explained and discussed, science doesn't really ever bother with defining and delineating a consensus. The consensus simply is. It is whatever most people in the field understand and agree with. There are always some who agree with X but disagree with Y, or vice versa. There's always a Z that's so basic and given that everyone but crackpots agree with it, and a W that's so far out of the mainstream that no one takes it seriously. The point is that there is no structure. Scientists don't get together once a year at the annual consensus convention and vote on which parts of science will or will not be considered accepted. Scientists get up in the morning. They go to work. They study, research, think and publish, and read each other's papers. Over time, like a hive mind, a social network of understanding evolves. What you are doing with the range of climate sensitivities is to muddle that, by taking the simple idea that every scientist has what he believes is a likely range of sensitivities, and instead conjuring a world where each scientist picks a specific number, and then claiming that because there are so many different numbers, there cannot be a consensus. This is all typical denier nonsense, intended to confuse people and sew doubt. The bulk of scientists know what the likely range of sensitivities is. A small group of fringe scientists expect sensitivities outside of that range. This does not mean that scientists are at all confused on the issue (which is what you ultimately are trying to imply with your own personal redefinition and portrayal of a consensus).
72590. CBDunkerson at 22:55 PM on 14 October 2011
       Climate 'Skeptics' are like Galileo
       saltspringson wrote: "So, suppression of some scientists by other scientists is OK?" Yes. Quacks who claim that HIV does not cause AIDS (ditto smoking and asbestos not causing cancer), 'scientific' advocates of 'racial purity', homeopathic 'medicine' practitioners, and other such dangerous frauds absolutely should be 'suppressed'. 'Scientists' who endanger lives by spreading blatantly false claims to the general public need to be stopped.
72591. Dikran Marsupial at 22:52 PM on 14 October 2011
       There is no consensus
       Jonathon I note that you have not addressed either of my comments. However, the consensus view is not that the plausible range is all positive values, if you want to see what the range of plausible values is then lets discuss it on the thread devoted to that issue i.e. How sensitive is our climate?. There you can find peer-reviewed research on the plausible ranges according to different methods. Your argument is essentially a straw man, I don't particularly see any point in arguing about it either, but if you change your mind, please take it to a more appropriate thread.
72592. Jonathon at 22:45 PM on 14 October 2011
       There is no consensus
       Dikran, The argument that everyone is in agreement, because we all think that the value is positive, is nice, but does not tell us much. If that is the extent of the consensus, then we should just drop it altogether. Since no one wishes to go beyond that issue, there is really no point arguing any further.
72593. Dikran Marsupial at 22:38 PM on 14 October 2011
       There is no consensus
       Bibliovermis, 3 is on the high side of 3, but only for large values of 3 ;o)
72594. Jonathon at 22:37 PM on 14 October 2011
       There is no consensus
       Biblio. That is for equilibrium climate sensitivity. I though you were talking abobut transient sensitivity, which the first article states as 1-3, while the second says 1.3-2.6. In either case, 3 is on the high side for transient sensitivity. Please read more carefully.
72595. Sudden_Disillusion at 22:35 PM on 14 October 2011
       Climate 'Skeptics' are like Galileo
       @saltspringson 1. you really think the whole thing is a big conspiracy theory of tens of thousands of scientists around the world trying to suppress a couple of poor little fellas who own THE TRUTH? What do you think is more likely: AGW or your so-called "suppression"? 2. Sorry again: all of the evidence for AGW relies not on computer models but on, yeah right, observations in a vast array of different proxies. Regarding the Trenberth paper: you are just cherry-picking. This paper only shows that we do not understand everyhing yet. It does not prove your point at all. Classic denial behaviour. 3. And again a big sorry: CO2 = GHG, GHGs warm the atmosphere. Humans blast >5Gt CO2/yr into the atmosphere (CO2 stays there for like hundreds of years meaning we accumulate CO2 there). The-se are facts. It does not mean we are solely responsible for GW but we massively add to it. The only thing we don't know is how bad it's gonna be. 4. Why should Mann be dragged into court exactly? For saying what is instead of cherry-picking or misinterpretating data? Besides all your arguments are missing the most important point: It is not rational to disturb a highly complex and functioning (i.e. life-supporting) system (Earth's climate) as we do on a large scale be-cause if you do there will be consequences but you don't know what they are and how big their impact will be. Basically, you do not conduct an experiment on a global scale of which you do not know the outcome. Case closed tbh
72596. JMurphy at 22:34 PM on 14 October 2011
       Pielke Sr. and SkS Disagreements and Open Questions
       peilkesr wrote : "Policymakers, in my view, are being misled into believing that the climate should more-or-less monotonically warm when in reality both natural variability and the diversity of human climate forcings makes the issue of climate system heat content much more complex." Some examples have already been given as to the sort of people who are indeed trying to mislead policymakers (one of whom has recently actually published details for the picketing of a climate scientist; the other of whom has his own myth-making on this topic exposed and rebutted on SkS); and Albatross on another thread has given plenty of examples of SkS trying to make sure policy makers are indeed properly informed - another link here. In fact, the person who hosts the site at the first link I have given, has plenty of posts about cold, snow, everything-but-CO2-affects-the-climate, everything-is-going-to-be-OK-really, etc., but very little about heat records or explanations as to how temperatures do not rise monotonically - in fact, a recent post ("Breaking: A peer reviewed admission that “global surface temperatures did not rise between 1998 and 2008″ – Dr David Whitehouse on the PNAS paper Kaufmann et al. (2011)" - given over to a post by those 'unbiased' chaps at the GWPF) seemed designed specifically to mislead, and none of the commenters there were informed by the blog owner (who does regularly reply to those he believes are misinformed) that their comments were misleading, etc. But who do you (Dr Pielke) believe is doing the misleading ?
72597. Bibliovermis at 22:33 PM on 14 October 2011
       There is no consensus
       The article you posted states that the most likely climate sensitivity is 3 deg C. How is 3 on the high side of 3?
72598. Jsquared at 22:33 PM on 14 October 2011
       The Earth continues to build up heat
       About the graph at #3: the corresponding graph at RealClimate doesn't have the error bars (+ or - 1 sigma dotted lines). I think they are crucial to the figure: the data show that 0-2000m contains less heat than 0-700m from 1955-1975. I don't think that's possible, so it has to be noise in the measurements. The problem appears to go away when you look at the error bars. That makes it ewen more immportant to have the original source for that figure.
72599. Dikran Marsupial at 22:31 PM on 14 October 2011
       There is no consensus
       Jonathan wrote: "The disagreement is about what is that range," as far as I can see you have provided no evidence that there is substantial disagreement regarding the range of plausible values, just that there are point estimates that are not in close agreement.. "and is it narrow enough to constitute a consensus." The spread of the range of plausible values has no bearing whatsoever on whether there can be a concensus on what the range actually is. If we had some dimensionless quantity that physics constrained to be strictly positive, but otherwise we knew nothing about it, then it would be perfectly reasonable for the concensus to be that the plausible range were from 0 to +infinity.
72600. banana at 22:27 PM on 14 October 2011
       Continued Lower Atmosphere Warming
       Firstly, thanks for a well-written and informative post. Would it be possible to add uncertainties to the measured trends (e.g. 0.18C since 1999)? Presumably they are quite large for such short time-periods, and this would help emphasise how they are not particularly useful. Significance tests would serve the same purpose. I'm also interested in what sort of studies have been done regarding the linearity/non-linearity of various aspects of the climate system. Any references would be greatly appreciated - sorry if this request is too vague.

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