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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Comments 41301 to 41350:

  1. ONLY HOURS Left to Be Part of a New Collaborative Approach to Media Coverage of Climate

    Let alone climate science coverage, more and more as a public we're expected to offer useful guidance on policy hinging on science in general.  Without the help of competent science journalism we may as well be making decisions by throwing darts over our shoulders. As Stephen says, tragically for all of us science journalism is a vanishing species of news content, even as it is more necessary than ever before.

    The project Stephen describes will help provide a vital breath of life to science journalism in general, beyond the topic of climate change; fostering and encouraging young journalists to cover scientific topics will be richly rewarding for us all as we try to shape our future in a properly informed manner.

    So go forth and multiply! Don't look left, don't look right, just go. 

  2. Why climate change contrarians owe us a (scientific) explanation

    Andrew, further to that - accurate prediction is about understanding what is happening and why. Quantification means being able to model the process with well-understood physics.

  3. Why climate change contrarians owe us a (scientific) explanation

    Andrew, the question is why is the bottle of beer warming. If you postulate that say it is warming because the air temperature around it is warmer than the beer, then you could determine things like thermal properties of glass and beer, and then see whether observed warming was consistant with Fourier law. That doesnt mean hypothesis is proved - there could be a say a chemical reaction due to an additive to beer and an masking refridgerator element to give rates consistant with Fourier law - but it does give you some confidence in then using simple heat transfer to predict the future state of the bottle temperature.

    However, if you had a network of very accurate thermometers within the beer, then you would observe more complex temperatures changes going on within the fluid because of internal convective currents within the bottle. Predicting the evolution of temperature on these thermometers would be a very complex task with a lower degree of predictability. However, if the beer is cold and room is warm, you have little difficulty in predicting the average temperature of the beer  over say 10 minute intervals and how fast it will warm to room temperature.

  4. Why climate change contrarians owe us a (scientific) explanation

    Andrew7x8, no.  Analysis of the physical situation is required.  Simply extrapolating a trend in that way can leave one literally dead.  If I stand in the middle of the street and am not hit by a car for 10 minutes, does it mean that I will never be hit by a car?  If we know why the bottle is warming, we can assess how long the conditions are likely to persist.  We know why the climate system is warming, and that--not the surface trend--tells us that it's likely to persist for centuries.

  5. Does the global warming 'pause' mean what you think it means?

    Michael M - didn't they have a higher confidence level above 4.5 C than they had for less than 1.5?

  6. Why climate change contrarians owe us a (scientific) explanation

    If a scientist observed a bottle of beer warming on a table, and noted how the temperature changed over some time interval, could they make a scientific statement about the warming, and/or predict the future temperature?

  7. It's waste heat

    And just a more realistic calculation:

    With average surface temperature at 288K you have surface heat flux of 390W/m2 (see Keihl and Trenberth for measurement details - but matches Stefan-Boltzmann law pretty well - try it yourself). Increase heatflux by 0.028W/m2 and you get a temperature increase from S-B law of 0.0052, with emissivity of 1. A very long way from 1/10 degree.

  8. 2013 SkS Weekly Digest #42

    First-person views of adaptation to climate change, via Australian firefighter helmet cameras. 

    Adaptation is a deceptively soft word. 

  9. It's waste heat

    "Given that waste heat is readily shown to equate to warming the entire mass of the atmosphere by some 1/10 deg p.a."

    No it doesnt. Perhaps if you show us your working, it might help pinpoint your misunderstanding but you seem to be missing the very basics of physical understanding here. You cant just turn bits of physics off (like Planck's law) and try an compartmentalize things by looking at only part of the processes at work.

  10. It's waste heat

    Old Sage,

    You need to go back to High School. In my High School AP Chemistry class, the students learn that heat is heat.  It does not matter if it comes from the sun or from waste heat, it is the same once it gets into the atmosphere.  When you say absurd things like: 

    "Waste heat is almost entirely applied to the kinetic heat of atmospheric gases and it is trapped until transported by mass transfer down prevailing winds to cooler regions. It cannot get out by radiation."

    and

    "Gases under the conditions applying to the vast bulk of the atmosphere do not convert their kinetic energy into e-m radiation."

    everyone else  knows that you have no idea what you are talking about.  Please provide scientific references for your wild claims.  I note that you have provided no references, only unsupported assertions of fact.  In fact, like all the rest of matter in the universe, the atmosphere radiates black body radiation.  The energy from waste heat is radiated into space like the much greater amount of energy that is received from the sun.  What possible mechanism could differentiate the heat from the sun and the heat from waste heat?  Heat is heat.

    Keep in mind that this is a scientific board.  Other people know what they are talking about even if you do not.   

  11. 2013 SkS Weekly Digest #42

    An interesting news on the NSW fires worth pondering on.

    state of emergency declared as bushfire conditions worsen

    Extraordinary precaution policy have been activated by the premier - forced evacuation by police and demolition of buildings if necessary. That's what he said inexplanation:

    "I'm sure it will be [controversial]. There isn't much in the fire-management business that isn't controversial … But I'd rather be copping criticism in two or three days' time for what didn't occur."

    Note that this is the same person who denies the necessity to address global warming (essntially repeats the talking of his federal counterpart and colleage Tony Abbott) thus does not make a connection between those two issues. Obviously, he may not be facing the consequences of the related issue yet, but his successor definitely will.

  12. IPCC model global warming projections have done much better than you think

    John Hartz @114, the Summaries for Policy Makers are "approved" by the IPCC, ie, subject to line by line debate and voted on, line by line.  In contrast, the reports themselves are only "accepted", ie, they are voted on to be accepted as a block.  Consequently, while box 9.2 (the discussion of the hiatus) may have been composed with the comments of non-scientists in mind, it was composed by scientists and not subject to individual veto as to its wording.  I am unsure as to whether the government representatives would have had to reject all of chapter nine, or all of the WG1 assessment in order to reject the wording in box 9.2, but their failure to do either cannot be regarded as constituting specific editorial control over the wording of the box.

  13. It's waste heat

    I haven't replied to my various critics here before because I despair of the disconnect between the various scientific principles others have cited and the context in which they haver been applied. What makes Physics a difficult subject for some is that what is true under some conditions can be just the opposite under others.

    For instance a factor of 100 is argued above as the difference between waste heat and GHG forcing so the former is therefore irrelevant to global warming. Given that waste heat is readily shown to equate to warming the entire mass of the atmosphere by some 1/10 deg p.a., the two numbers must be describing totally different things. Waste heat is almost entirely applied to the kinetic heat of atmospheric gases and it is trapped until transported by mass transfer down prevailing winds to cooler regions. It cannot get out by radiation. If GHG forcing is supposed to measure the rate at which GHG's are heating the atmosphere, then I'd like to know where it is going because at 100 times waste heat it is unsupportable. Gases under the conditions applying to the vast bulk of the atmosphere do not convert their kinetic energy into e-m radiation.

    The energy balance of the earth's atmosphere has been exactly zero to all intents and purposes for thousands of millions of years. The perturbation represented by waste heat applies to scales in balance by natural processes and it is large incomparison with zero. It is moreover, bang on quantum for the scale of consequences observed. 

    The emphasis on CO2 by the IPCC is tantamount to saying the carbon cycle governs Earth's temperature. In that case, how did it get to support life in the first place?  Earth has an extremely robust set of physical properties which have returned equilibrium after cataclysmic events. It could even be argued that the burning of fossil fuels by increasing CO2 and reducing O2 would cause more sunlight to be sequestered by photosynthesis according to proven chemistry principles thus tending to lower energy available for heating - given we had not swapped vegetation for concrete.

    We might understand the warming better if we took account of the physical stabilisers. Stefan and T^4 applies to the huge inertia of the global surface. Any perturbation due to an atmospheric source - eg CO2 - of tiny inertia would have to be seriously amplified before any correction kicked in from Stefan.

    An exception is water which vapourises relatively easily. Far and away the most responsive physical property to a warmer globe is more vapour. That means more condensate higher up absorbing and re-radiating near the TOA so reducing takeup of solar energy.

    Another property is the vigour of the atmosphere related to which will be activity in the plasma which floats upon it and in the earth's field. That will act as a generator as will violent electrical storms and they emit energy in the visible spectrum as well as longer. More than half of that will escape earth due to geometry.


    So the CO2 argument is a simplification which buys time for those who worship the totem of economic growth- mostly from population increase - the real source of mans climate impact. It is far more multi-faceted than that but then the drive to claw back energy from sun and wind does indicate that despite the apparent lack of economic justification someone has worked it out.

  14. Does the global warming 'pause' mean what you think it means?

    Vroomi, yes, I also have the problem with the tingly anntennas....

    Dean, you may have a problem regarding uncertainty: There is a likelihood, that the equilibrium sensitivity is as low or lower than 1.5  - but you forget that uncertainty is not or friend! Because there ist just (or nearly) the same chance, that the equilibrium sensitivity is as high or higher than 4.5°C.  On my part the best message in the whole sensitivity discussion ist that it is very unlikely to be higher than 6 degrees.  (Judith Curry once, pushing uncertainties as always, claimed the ES may be up to 10 degrees .... that was the scariest "argument" I ever heard, let alone from a "sceptic")

    A discussion to ES, in german: IPCC 5 - Uneinigkeit zur Klimasensitivität

    Discussion with AR5 , graphs pages 172(ES) and 173(TS)


    PS: Dana, with your Enigo Montoya reference you made my day! :-D

  15. Does the global warming 'pause' mean what you think it means?

    vrooomie and Matt, I don't think that there is anything particularly wrong with main stream climate science and I respect the IPCC reports as goldmines of scientific information.  But I have spent a fair amount of time arguing with "skeptics" and would like to have a consistent understanding of the current state of knowledge.

    As I wrote, I cannot reconcile the lowered equilibrium sensitivity (lower end)  with Dana's explanations about the "pause", At least one expert has claimed:  "The lowering is based on one narrow line of evidence: the slowing of surface warming during the past decade".

    But if the "pause" has nothing to do with weaker feedback mechanisms, this a contradiction. Larger natural variations even points to stronger positive feedbacks.

    Reading through the report there is quite a lot of mentioning about the period 1998-2012. But there is no systematic scientific reason for this, it is cherry-picking. As a non-expert I don't really want to claim that the IPCC authors are wrong, but lets say I'm rather skeptical against some of their assessments and would like to have confirmation that the lowering wasn't just due to the massmedia/politically driven pressure.

  16. IPCC model global warming projections have done much better than you think

    @VeryTallGuy #112:

    Also keep in mind that non-scientists had a hand in crafting the final wording of the WG1 summary report. 

  17. Does the global warming 'pause' mean what you think it means?

    "Was he not just asking that, given the ocean's ever-increasing heat content (as per the article) and despite the cool sun/La Nina dominance slowing surface temps very little, how could the IPCC possibly extend the lower bound of projected ECS down to 1.5degC? "

     

    Not sure, and it's why I asked. As a long-time veteran of seeing deniers creep into conversations here and across the Web--and I am NOT asserting Dean is one--I have 'tingly antennae' about curious questions like that, ergo, why I asked, Dean hopefully will lean in and elucidate further on his intent, and I'm happy to hear it out.

     

    Remember that the IPCC bases it reports on the severe side of 'least drama,' given the makeup of its constituent membership: their downgrading CS may or may be a function of that, or, perhaps more likely, is a function of science doing as it always does, and should: consider ALL rational, data-driven conclusions.

  18. Does the global warming 'pause' mean what you think it means?
    vrooomie,I'm sure he'll correct me if I'm wrong but I didn't read the second part of Dean's post as questioning the science, as you appear to have potentially identified it?... Was he not just asking that, given the ocean's ever-increasing heat content (as per the article) and despite the cool sun/La Nina dominance slowing surface temps very little, how could the IPCC possibly extend the lower bound of projected ECS down to 1.5degC? Oncologists aside, doesn't he agree with you that this seems an unlikely scenario?
  19. 2013 SkS Weekly News Roundup #42B

    jyushchyshyn, it's a sad fact that human nature dictates we respond better in aggregate to price signals than common sense. Of course you're technically speaking correct in saying we can solve this problem by ending demand for hydrocarbons as fuel, but  in reality we won't do so without encouragement in the form of our wallets deflating more quickly.

    Let alone the awesomely nasty nature of Canada's own Mordor, each and every source of petroleum that is removed from our imperfect accounting system helps to contribute a little bit to our price signaling. 

  20. 2013 SkS Weekly News Roundup #42B

    re Canada’s efforts accelerate a global tragedy of the climate commons

    Let's stop one pipeline and call the problem of global warming solved, and continue to burn coal, drive SUVs and import OPEC oil.

    If you want to stop new pipelines from being built, cut them off at the source. Switch to the new energy sources and there will be no demand for the oil which new pipelines would deliver.

  21. Does the global warming 'pause' mean what you think it means?

    Dean, not sure how to answer your question at 16, but your post certainly does raise my antennae..suppose a team of *extremely* well-educated experts in a given field--say, oncologists--have studied my files, data, and extensive and comprehensive collection of CT scans and arrives at an opinion--a consensus, if you will--of my having an 83% chance of dying from an aggressive cancer.

    How would it be rational, for me, to exclaim, "Well, shootfire, boys! That means I have a fair 17% chance of all of you, being wrong!" I'm asking the question because the final part of your post made me twig at the rest. would it be rational for me to proceed with the experts' 83% estimate of my mortality, or to run with the slim chance that 17% of them felt there was no worry?

    I am sure the brainiacs among the SkS team can certainly address the first part of your post, and I am also interested in that, given how bad I am at stats.

  22. Dikran Marsupial at 00:39 AM on 20 October 2013
    IPCC model global warming projections have done much better than you think

    Conventional statistical regression cannot be used to make reliable caual inferences as they are based on correllations, and correllation is not causation.  They can be use to show that X can explain Y, but we cannot say that X does explain Y as there may be some other cause that is not represented in the model, or there may be confounding variables, etc.  If this were not the case, we could regress GMSTs on the surface area of ladies undergarments and conclude that CO2 does not cause climate change

    Underwear (to some extent) can explain global warming, but that does not mean that to any extend underwear does cause global warming.  Likewise, the fact that including ENSO in a regression model add explanatory power, that does not mean that ENSO is the cause of the variability it explains. 

    The use of models similarly shows that ENSO can explain the variability in GMSTs, but it doesn't establish that it actually has caused the hiatus.  The reason it does not is because we cannot be absolutely sure that it explains it for the right reason (note constraining SSTs means that the transfer of energy between the air and ocean does not obey the laws of physics correctly).

    Now the fact that we cannot obtain certain knowledge from observations means that in practice we need to use other criterion, such as theory, to arrive at the best explanation of the data.  Thus I have no problem at all if someone finds the regression models sufficiently convincing to be sure that ENSO is the cause of the hiatus (which is actually fairly close to my position - I'm pretty confident that it is just ENSO), but the regression model itself does not establish a causal link.

    VeryTallGuy - generally the IPCCs comments are well thought through, provided they are interpreted as clear statements of the scientific position, expressed by scientists who know the issues well, intended as statements for the record.  They are not however generally well worded as statements intended to resolve misunderstandings in the blog debate on climate, nor are they expressed in terms that prevent any possibly (even willfull) misunderstanding.  I think the IPCC are doing the right thing in expressing the science in a manner designed for a primarily scientific audience.

  23. Why Curry, McIntyre, and Co. are Still Wrong about IPCC Climate Model Accuracy

    Tom Curtis,

    Healthy skepticism is warranted. I have more info here on the general approach:

    http://contextearth.com/2013/10/04/climate-variability-and-inferring-global-warming/

    The October 1943 spike is the single anthro effect I added apart from CO2. You can turn that off by checking off anthro aerosols. I added that because since the overall agreement is so good, one can really start to look at particular points in time for further evaluation.

    All the lags can be modified by the user. You can turn all of them off by setting the lags to zero. The agreement is still good.

    The application of the LOD (length of day) is crucial as a proxy for multidecadal oscillations. This ensures conservation of energy and conservation of momentum according to work by Dickey et al at NASA JPL [1]. The fluctuations in kinetic energy have to go somewhere and of course changes in temperature are one place for this dissipation.

    As far as volcanic disturbances, I took the significant ones from the BEST spreadsheet of Muller. If you can point me to the volcanic fording data from GISS, I can use that instead. Thanks !

    [1]  J. O. Dickey, S. L. Marcus, and O. de Viron, “Air Temperature and Anthropogenic Forcing: Insights from the Solid Earth,” Journal of Climate, vol. 24, no. 2, pp. 569–574, 2011.

  24. Does the global warming 'pause' mean what you think it means?

    There is one thing that I don't understand. It said that the IPCC lowered their likely equilibrium sensitivity interval from 2-4.5 to 1.5-4.5 due to the "pause" (or rather due to simplified models that were very sensible to this kind of short term variability). Independent paleo data, GCM:s and observations of feedbacks does not support any (likely) values <2.

    But if the climate system even accumulated more heat during the "pause", as claimed in the blog post, despite weaker sun and (probably) stronger negative aeorosol forcing, how can this be consistent with the IPCC assessment update, including a fair chance (17%) of sensitivity being even <1.5?

  25. IPCC model global warming projections have done much better than you think

    Dikran, Tom,
    thanks for the perspectives, very interesting and appreciated.  I must admit, compared to much of the IPCC output the bit on the "hiatus" comes across as not particularly well thought through.

  26. 2013 SkS Weekly News Roundup #42B

    Re the mess caused by the shutdown, I'd like to see a clearinghouse set up for researchers to describe the impact on their work.

    I know of a major meeting here in Seattle to do with earthquake resilience that was thrown into chaos thanks to the GOP's psychotic clown posse. Researchers coming in from New Zealand and other places at great expense arrived to find that their USGS counterparts could technically face fine and imprisonment* for meeting as agreed, ages ago. Not only were we wasting our own time but that of others. We're also destroying our credibility as reliable partners. 

    Other people I know faced similar absurd problems. Seeing all of this waste summarized in one place would be helpful and instructive. 

     

  27. Does the global warming 'pause' mean what you think it means?

    Maybe I missed it but claiming something about a change in the slope of global warming is nonsense. Now if the sign of the slope changed, I'd be interested but to quibble about the value of the slope?

    The honorable global warming deniers are face with some hard, undenible facts. Arctic shipping through the NorthEast and NorthWest passage exceeded 1 million tons in 2013. It was 1.2 million tons in 2012 and similar numbers of ships,  tonnage unknown, in 2011. The practical effect, the business effect, is Arctic shipping is open for the third year in a row.

    So if this is just a slope problem and not a sign, hammer them away with "Is it cooling now?"

    Bob Wilson

  28. Does the global warming 'pause' mean what you think it means?

    I just rebutted a piece by a local TV meteorologist here in Toronto, and I used an "office building analogy" to explain the pause in global warming.

    See what you think of it. I'm wondering if I subconciously "borrowed" it from someone here at SKS...

    The scientists understand how “temperature” is not the same thing as “heat”. They have a good understanding of how surface temperatures are coupled to global heat content and how ocean currents affect surface temperatures. Farnell’s point is false because surface temperatures can drop while the Earth still warms (over short time periods). The folly of point 1) can be illustrated with this example:
    Imagine an office building with 10 floors. Now picture yourself sitting on the 10th floor of the building and making this claim,
    “No one must be entering this building since the number of people on the 10th floor has not gone up.”
    Imagine making that statement above while simultaneously looking out the window and noticing the number of people entering the building is greater than the number of people leaving the building. Point 1) is like that. Its conclusion does not follow from its premise, and it is observably wrong.

  29. Does the global warming 'pause' mean what you think it means?

    caroza @12

    hmmh, an analogy may be a bedroom: the person in bed is the heat source, the blanket the top layer of the ocean, the air in the room all deeper layers; the bedroom is thermally well insolated. Findings, with heat source constant:

    • the blanket heats up quickly but then stays at equilibrium Temp., the air in the room will heat up more slowly over time although the blanket does not change Temp. any more
    • if you shake out the blanket regularly (ENSO), then put it back in place, it will cool a little temporarily while the room keeps heating
  30. IPCC model global warming projections have done much better than you think

    VeryTallGuy, first (and with all respect), Dikran Marsupial has misinterpreted me.  I do say that ENSO is the dominant cause of the "hiatus" (better, slowdown), not that it could explain it.  Of course, it is always possible that I am over interpreting the evidence, and that Dikran's claim is more accurate given the evidence.  That would be the case if global warming would have accelerated absent all factors contributing to the slowdown.  In that case, the contribution of ENSO could be sufficient to almost completely explain the reduction in short term observed trend relative to the long term observed trend, but changes of forcings could likewise explain a similar amount.  In that case, temperatures without these short term influences would have accelerated to an approx 0.25 C per decade warming trend.

    With respect to my actual claim, however, it is not inconsistent with that in the IPCC.  To be specific, my claim is that, when compared to all other individual factors influencing the slow down in global temperature rise, ENSO has a significantly larger influence than any other individual factor; and that the influence of ENSO is not much smaller (if smaller at all) then the sum of all other factors.  That is what is mean by "dominant".  In contrast, the IPCC claims that the sum of the influence of natural variability is not much different from the sum of the influence of changes in forcing.  Thus, there may exist natural variability of opposite sign to the ENSO influence, reducing the net impact of natural variability relative to the net impact of changes of forcings.  Or the influence of ENSO based natural variability may be greater than the combined influence of changes in forcing, with the two individual factors contributing to change in forcing each individually being significantly smaller than the ENSO influence.  In both these cases, both my claim and that of the IPCC would be correct.

    A third possibility is that the IPCC understates the influence of natural variability.  Given that the IPCC did not have access to Kosaka and Xie (published online in late Aug 2013, and not included in the IPCC references), that is plausible.  Equally plausibly, a new study may come out showing Kosaka and Xie's result to not be reproducible, or to have overstated the influence of ENSO (in which case my opinion would revise back towards that of Dikran Marsupial and the IPCC).

    So, to summarize:

    1)  My claim, which assumes a linear base trend in global temperatures, may be incorrect and the IPCC's correct because global temperatures would have shown an accelerating trend absent both the ENSO influence and the reduced forcings;

    2)  We could both be correct, with the ENSO influence on the lower end of what I expect based on the evidence but still the dominant influence (ie, greater than 50% and >> than any other individual influence);

    3)  Either I or the IPCC could be wrong, they because they present a snapshot of the science as it existed 6 months ago; or I because the most recent evidence (on which I rely) is overstated in some way.

    Finally, I note that the IPCC discuss the influence of the PDO rather than ENSO.  That is not a difference between us in that the two are closely related, with PDO states causing dominant influences of La Nina or El Nino (depending on whether the PDO is +ve or -ve) in ENSO; or because the PDO is just a filtered effect of ENSO on the north Pacific.  (SFAIK, it is not as yet clear which of these is the case.)

  31. Why Curry, McIntyre, and Co. are Still Wrong about IPCC Climate Model Accuracy

    WebHubTelescope @190, can you direct me to documentation justifying the SALT model method, because on a casual perusal I am far from impressed.  

    My initial concerns were raised by the tunable, and different lags for different forcings.  If you allow yourself to tune lags, I am sure you can get some very good fits between models and observations, but a physical explanation as to why solar forcings should have half the lag of anthropogenic forcings, and nearly one sixth that of volcanic forcings is decidedly lacking.

    On closer inspection, I am even more perplexed.  The "fluctuation components" show a very large, unexplained "linear" adjustment peaking at 0.396 in Nov 1943, and apart for its rapid fall off, is essentially zero at all other times.  That is by far the largest single fluctuation value on the chart, and has no apparent physical basis.  The lod adjustment is also unexplained (what does lod stand for?) and is certainly not a component of the GISS model forcings.  Further, the volcanic "fluctuation component" does not match the GISS model forcings from the 1920s to 1940s.

    Without documentation, it appears from the "fluctuation components" chart that arbitrary "fluctuations" are added as necessary to ensure a fit between model and observations.  If so, we should be less than impressed that a fit is then found.

  32. Does the global warming 'pause' mean what you think it means?

    dana @ #5, would it make sense that as the oceans warm overall, upper layers might cool?  I remember reading years ago (can't remember where, sorry) that as the ocean warms it mixes better and becomes less stratified.  I assume that's still true although I don't know what sort of temperature increment results in what sort of degree of mixing.  But it occurred to me at the time that as the deeper ocean warmed, if it mixed better with the layer above 2000m then that might cool the upper layer (for a while), given that the volume of water below 2000m is so huge by comparison to the thin upper layer, and relatively cold, so a tendency in the direction of thermal equilibrium might reduce upper layer temperatures..  Is that a possibility?  Sort of analogous to the weakening jet stream resulting in weather which is warm by Arctic standards but very cold by British or European standards dumping snow and ice all over Britain and Scotland and making the deniers happy because of the snow in their back garden. 

  33. Does the global warming 'pause' mean what you think it means?

    Sou at Hot Whopper has posted a pleasingly concise explanation of the major fallacy of Bob Tisdale's attempt to reply to Dana:

    Bob Tisdale rejects the greenhouse effect

    The seemingly rude title of the piece is unavoidable due to Tisdale's conclusions; the title is not impolite but is neutrally descriptive of the logical box Tisdale has constructed around himself. 

  34. IPCC model global warming projections have done much better than you think

    Perhaps the best way of showing the effect of removing *some* of the more or less known "internal variables" is... well, show it:

    Foster & Rahmstorf

    Foster and Rahmstorf (2011)

  35. Why Curry, McIntyre, and Co. are Still Wrong about IPCC Climate Model Accuracy

    For SteathGuy, I would recommend looking at energy balance models first. Go over to this web site that generates model-based fits to various temperature series and intereract with the graphs:

    http://entroplet.com/context_salt_model/navigate

    I spend too much time at Curry's site tryin to reason with the skeptics and I at least give you credit for trying to construct a somewhat methodical argument.  I just suggest that instead of looking at the GCMs at first, that you try to pull apart the possible independent factors that give rise to subdecadal and decadal climate variability. The snaphot below is a view of an interface that you can play with and see how the various lags have an effect on volcanic disturbances, TSI, etc.

    model explanation for AGW

  36. Does the global warming 'pause' mean what you think it means?

    Here's Tamino's take on one of Tisdale's recent posts: 

    http://tamino.wordpress.com/2013/10/05/bob-tisdale-pisses-on-leg-claims-its-raining/

    Moderator Response:

    [Sph]  This is a borderline violation of the Comments Policy (no links without context).  As it clearly relates directly to an analysis of Tisdale it is applicable (although, too, the whole Tisdale thing is in in danger of wandering off-topic), but in the future, please provide your own (better clarified) context around such a link.

  37. Does the global warming 'pause' mean what you think it means?

    garethman - That's a very good point, rhetorically "plausible" often has little connection with "likely" or "reasonable". Folks like Monckton make it a way of life, sounding entirely plausible while under closer examination what they are saying is utter nonsense. (Sounds great - just don't think about it...)

    General items that jumped out at me in Tisdale's piece, which I've come to associate with unsupportable 'skeptic' nonsense:

    • Short time frames, focus on small regions of the oceans/world (cherry-picking)
    • No statistical analysis of trend(s) versus variation (i.e., math), just rhetoric that any statistical analysis would show invalid
    • Claims that 'models fail', ignoring the physics basis
    • Red herrings - for example, going on about models when the article under discussion is about observations
    • Claims that the variable of interest isn't measureable (when that actually invalidates their own argument(s) as well)
    • And "Buy my book", when said book has no peer-reviewed support

    I may have have missed a few bits of nonsense - I didn't bother to check every assertion. But when there are so many red flags, I consider it safe to conclude that the article containing those errors isn't saying much worth reading. 

  38. Does the global warming 'pause' mean what you think it means?

    Thanks KR, I did indeed write that, but that is from a lay persons perspective. I wanted to check how accurate his essay was and a useful way of doing that is to get the experts here to dig a bit deeper and explain any mistakes in a way that I, as a lay person will be able to make sense of. The word interesting by the way can be applied to many things, they do not have to be correct! In some ways it is really difficult and long winded to check out all the facts in any essay item by item on both sides, thats why it is really helpful to have critical appraisals in this way by people who have previous experience.

  39. Dikran Marsupial at 00:48 AM on 19 October 2013
    IPCC model global warming projections have done much better than you think

    VeryTallGuy, I would say Tom's arguments show that most if not all of the hiatus can be explained by ENSO, but cannot show that it is caused by ENSO.  Thus both Tom and the IPCC are right AFAICS, looking for other causes of the hiatus is just part of normal science (keeping an open mind), however Tom is right in suggesting that there is no pressing need for an alternative explanation as it is already quite well explained by ENSO.  This sort of thing is a limitation of science, it is very difficult to show that X caused Y, only that Y can be explained by X.

    The way science works is that if you can't show that the existing explanation doesn't explain the observations, or that your hypothesis provides a better explanation, then you probably shouldn't put much confidence in it.  At the moment ENSO (i.e. internal variability) is a sensible null hypothesis, and it explains the observations pretty well, without ruling out alternatives.

    Personally as a statistician, I am still waiting for statistically significant evidence that there actually has been a hiatus (i.e. a change in the underlying rate of warming).  It is possible that there is actually nothing that needs to be explained in the first place! ;o)

  40. Science of Climate Change online class starting next week on Coursera

    I'm teaching a section on climate change and the censoring of science in my Theater and Justice Class at John College of Criminal Justice: dramatic readings An Enemy of the People, my play Extreme Whether about climate change scientists and deniers, and Euripides The Bacchae.  I've gathered some basic readings about climate change, but wonder  if you have suggestions.  I would also hope to see climate change and global warming integrated more broadly into (what is left of) The Humanities.

  41. Science of Climate Change online class starting next week on Coursera

    I have watched David Archers original videos of his lectures based on his book.
    I found them very useful in understanding the basics, so I imagine the new course will be just as good with the new materials and additional learning facilities that Coursera enables.

  42. Does the global warming 'pause' mean what you think it means?

    Tisdale also dismisses peer-review, claiming his data is from peer-reviewed sources (although certainly not his statistically unsupportable conclusions), and that the post here isn't peer-reviewed. 

    The SkS post isn't peer-reviewed, of course - but it's reporting peer-reviewed conclusions (IPCC AR5, not to mention a more direct reference to Nuccitelli et al 2012). And that's the major difference - the conclusions regarding OHC described in the IPCC are supported by science and good practice, while Tisdale's conclusions are based on cherry-picking, misunderstandings of statistics, and confirmation bias towards his personal "it's all ENSO and climate shifts" framework. 

    garethman - Over on WUWT you wrote "I suppose Dana’s essay and Bob’s both seem pretty plausible...". I would have to disagree. 

  43. IPCC model global warming projections have done much better than you think

    KR, I think you misunderstand me.  I wasn't trying to suggest that ENSO isn't part of natural variability.

    Tom presents a view that ENSO explains most if not all of the hiatus (using IPCC terminology)

    AR5 seems to focus on volcanoes and solar, and does not split out natural variability at all.

    So I wonder if I'm missing something, and Tom seems well informed to comment.

  44. Does the global warming 'pause' mean what you think it means?

    I'm confused how Tisdale's response could possibly be qualified as "interesting" -- he has already written the same before, Nuccitelli here is pointing out Tisdale (among others) is wrong in several ways, Tisdale responds by ... making exactly the mistakes that Nuccitelli is pointing out in this article?!

  45. Does the global warming 'pause' mean what you think it means?

    As usual Tisdsale is still focusing on surface temperatures and ignoring ocean temperatures.  He does have a valid point that 0-700m ocean warming has slowed a bit, but only because 700-2000m ocean warming has accelerated.  He's guilty of the same type of cherry picking I discussed above, just regarding surface ocean temps in addition to surface air temps.

  46. Does the global warming 'pause' mean what you think it means?

    Many Thanks for your response KR.

  47. IPCC model global warming projections have done much better than you think

    VeryTallGuy - "...from internal variability..." includes the ENSO, one of the primary and in fact easily identified internal variations of the climate. It's hardly unattributable. 

  48. Does the global warming 'pause' mean what you think it means?

    garethman - "Interesting", in the Bob Tisdale sense. Or nonsense, really. 

    Tisdale, as usual, focuses on extremely short time periods (2005-2013 for ocean temps, 2000-2013 for air temps, neither of which has statistical significance), on small regions of the world oceans rather than the globe as a whole (cherry-picking), on surface sea temps only while seemingly dismissing the energy accumulation in the volume (2D vs. 3D cherry-picking), disses the satellite temps while ignoring their agreement with surface temperature data sets, tosses out the old 'can't trust the models' myth, etc.

    He even attempts to toss all of the ocean heat content data by inappropriate scale comparisons - yes, the energy throughput of the climate is very large, but no, that doesn't block our ability to measure changes in temperatures. 

    Quite frankly, having looked at Tisdale's writings before, I would consider this one more (and rather boring) Gish Gallop of myths and misunderstandings. 

  49. Does the global warming 'pause' mean what you think it means?

    Bob Tisdale has written an interesting response to this as published in the Guardian. http://wattsupwiththat.com/2013/10/18/dana-nuccitelli-cant-come-to-terms-with-the-death-of-the-agw-hypothesis/#comment-1452081  I would be really interested to see how Dana views this response and whether he feels it is valid.

  50. Dikran Marsupial at 21:46 PM on 18 October 2013
    CO2 lags temperature

    dvaytw, yes the rate of warming per unit CO2 does indeed decrease with increasing CO2 concentration, which is why equilibrium climate sensitivity is usually presented as the temperature rise for a doubling of CO2, rather than for a fixed increment.

    CO2 solubility in the oceans is sensitive to both temperature and the difference in partial pressure of CO2 between surface ocean and atmosphere (Henry's law).  Fortunately the difference in partial pressure is currently a stronger influence than temperature, which is largely why atmospheric CO2 has only been rising at half the rate of anthropogenic emissions.

    David Archer is a top scientist working on the carbon cycle, and has some lectures etc. on his website that are well worth watching.  He has also written a nice primer on the carbon cycle (see also his papers via google scholar).

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