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Comments 41251 to 41300:

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

    Jubble @ 63,

    The scientific argument has clearly been won - there was never an argument in the first place.

    That's not true. Arrhenius' 1896 paper was thought to have been refuted for half a century due to a flawed experiment by J. Koch in 1900. (Interesting read.) It took a long time for the scientific community to come around.

    The irony, of course, is that "skeptics" now raise all the same objections that were raised and dealt with years ago by real scientists in forming the modern consensus view, all the while proclaiming that they are the ones fighting the closed-minded establishment that has "already made up its mind" oblivious to the fact that the "skeptics" actually represent the holdovers of the old estalishment view that took so long to overcome with scientific evidence!

    It's like Flat Earthers complaining that modern scientists are stuck in their ways and not considering new, alternative theories!

    This is also an interesting read that you might like.

    I have just posted the following on WUWT - let's see what sort of response I get:

    You may be surprised by what they think is convincing evidence. :-)

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

    MARoger @56 & JasonB @62: The scientific argument has clearly been won - there was never an argument in the first place.  

    The popular argument is very much up for grabs, though.  Throughout history, proving the science has only ever been the first important step of many before concerted action can be taken.  Examples are smog in London in the mid 20th century (4000 deaths in 4 days 1952 were initially blamed on influenza - it wasn't until 1956 that legislation was brought in) and of course tobacco.

    Climate contrarians (as they like to be known) will not produce the science, because it is not there.  They will instead try to denigrate the scientists, badging climate science as not a real science at all (other than those cherry-picked studies that can be woven into a superficially convincing argument for "natural variability"), and describing the IPCC as a corrupt group of inept close-knit non-scientists, rather than a panel summarising the work of 1000's of scientists.

    I have just posted the following on WUWT - let's see what sort of response I get:

    "I am looking to be convinced that AGW is a myth or not a problem. I admit that currently I believe that on balance it isn’t a myth and is a problem. My background is in science, with a joint hons undergraduate degree in Math and Physics from the University of Nottingham, England and a post-graduate in applied statistics (operational research) from the London School of Economics.

    Fire away – how can I be convinced? I’ve read “Climate – the Counter Consensus”, if that helps."

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

    Jubble @ 54:

    The main counter-AGW argument appears to be: The climate has changed before and no-one truly understands it, therefore there may be some other explanation of the current changes than anthropogenic that is not accounted for in the climate science and the models.

    That's an argument from ignorance, though. They may not truly understand it, but to say that no-one does asserts a level of knowledge on their part that they clearly lack.

    I think it's worth reiterating that AGW was not invented to explain "the current changes". The current changes were predicted long before they were observed — Svente Arrhenius' first computed a climate sensitivity of 4C in 1896!

    I would point those people to:

    1. Spencer Weart's "The Discovery of Global Warming", showing just how long the theory has been around and how it has evolved over time.

    2. Frank Capra's short film "The Unchained Goddess" from the 1950s talking about the possible consequences of mankind's CO2 emissions.

    3. Richard Alley's talk at AGU in 2009, "The Biggest Control Knob — Carbon Dioxide in Earth's Climate History", giving an excellent overview of the role CO2 has played in Earth's history.

    The fact that climate has changed before — and we know why — is one of the reasons we can predict what will happen this time!

    Thinking that, in spite of all this, the science might still be wrong and the problem may not be as bad as it currently seems, is wishful thinking for which there is no evidence and a bad risk management strategy. I think it's safe to say, as the OP essentially does, that a prima facie case has been made and the burden of proof has now shifted on to the other side if they wish to argue for inaction.

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

    SASM  @ 133,

    I think we all understand that this type of comparison isn’t meaningful in the initial stages of the forecast. But, as time advances forward the min/max trend lines become wider, and once they are as wide as the noisy temperature data, then the location of the origin really shouldn’t matter. For example, in your chart @126, you can see that the min/max trend lines are outside the 2.5%/97.5% model bands by 2013 or 2014.

    Nevertheless, in both my chart and yours, it is clear that global temperatures are at the very low end of the model projections. You show the +/-2.5% bands and the current HADCRUT4 data is touching the lower 2.5% band. I read that as there was only a 2.5% chance that the global temperature would reach this level.

    This is circular reasoning/begging the question. You're claiming that as time moves forward the min/max trend lines behave more and more like temperature bands, then use the observation that the temperature data is touching the lower 2.5% band to argue there is a problem.

    Tom's graph @ 126 very clearly showed the actual trend line that should be compared to the min/max trend lines. The actual trend line is about half way between the mean trend and the minimum trend. It is well within the range. QED.

    If you disagree, then how would any of you determine that the models are inaccurate? What is your method of testing and validation?

    Look at the second figure in the OP — Tamino's graph of projection trends and observation trends, together with their uncertainties.

    If they were disjoint — i.e. if the projected trends with their ranges did not overlap meaningfully with the observed trends plus their uncertainties, then we'd want to go back and figure out what we missed (or whether, instead, we had miscalculated something).

    We're a long way from that.

    BTW, as has already been pointed out, HADCRUT4 has a known systematic error because it omits the fastest-warming regions of the globe. The models have no such error in their temperature calculations. If you're getting close to showing there could be a problem (which you aren't, but at some point it's possible) then it's worth checking to see whether it's what you're using for observations that are the cause, rather than the models. (This has happened before, with UAH, for example.) Alternatively, you could apply HADCRUT4's algorithm to the model output to compare like-with-like.

    If your position is robust then it should stand up when using multiple data sets, not just the one data set that is known to underestimate warming. In other words, when you're right on the margin, you don't want to be accussed of cherry-picking the data set to prove your point.

    In this case, however, we're not right on the margin, but it's good to be prepared should we eventually be so.

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

    Leto @ 145,

    A professional poker player sits down with a novice. The hands and flow of money are totally unpredictable in the short term, but we know who is going to win by the end of the evening

    In fact, the entire casino industry is based on the fact that over a large number of games with a large number of people, a small bias in favour of the house will give them a profit even if they can't predict whether they will win or lose any particular game.

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

    Fossil fuel companies are not stupid and neither are they poor. They spend millions each year on research, scientists and technicians, Climate change is threatening their business and if it was a false science or if there was another way out they could easily spend the money on research and find it and prove it. Denying that is is happening is only wasting time and a lot of people are going to die.

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

    "You cannot have accurate long term forecasts and inaccurate short term forecasts."

    I just flipped 7 heads and 3 tails. The model that predicts very nearly 50%/50% distribution over 1000 coin flips, then, cannot be right.

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

    One other point for Elephant.

    "10 percent of children in the UK for example live in poverty. We also cannot provide our current energy needs."

    What is considered poverty is a rather relative measure. As is what you define as an energy "need"? You could also argue that poverty is actually a distribution problem and that having abundant energy isnt going to remove poverty. MacKay estimates UK consumption at 125kWh/p/d while USA manager 250kWh/p/d. By comparison Hong Kong manages on 80kWh/p/d and India on less than 20. I'd say there was scope to redefine "need" somewhat.

  9. Levitus et al. Find Global Warming Continues to Heat the Oceans

    Probably worth also have a scan of Von Schuckmann and La Traon 2011, "How well can we derive Global Ocean Indicators from Argo data?"

  10. SkS social experiment: using comment ratings to help moderation

    Jim Pettit, I'm well aware of the danger of denier gamification of the rating system (I read extensively on the topic before installing this system). Gamification is slightly more difficult at SkS because in order to rate, one needs to register a user account with a working email address. It's not impossible to register multiple accounts, by any means, but raising the bar does weed out a significant number of potential trolls. Because each rating is tracked, even if someone does gamify the system with multiple accounts, if they are detected, their ratings can be instantly removed. So there is very little return on investment for deniers wishing to undermine our rating system.

    But here's another interesting twist. There has been scholarly research into using social network analysis to detect sock puppets (multiple accounts by a single user) engaging in exactly this type of behaviour. If deniers do try sockpuppeting at SkS, they present a wonderful research opportunity. So bring it on :-)

  11. Ocean In Critical State from Cumulative Impacts

    Some interesting back and forth on this issue and lessons for the value of staying within one's boundary of expertise or at least being duly cautious can be followed here:

    Seattle Times series on local threats imposed by ocean acidification

    Respected local meteorology researcher Dr. Cliff Mass weighs in

    Author of Seattle Times piece Craig Welch responds to Dr. Mass

    An authoritative NOAA/Washington State report on the whole affair, "Scientific Summary of Ocean Acidification in Washington State Marine Waters" (pdf, 176 pages)

    Thanks for this article, John. We really do need to be more careful with the ocean and what's in it.

    (I should add that the NOAA/Washington item has includes truly excellent background information on the pH problem)

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

    Elephant.

    "I am entitled to that opinion and that is what I say."

    You are entitled to your own values and political opinions, but you cannot have your own version of reality. What you are saying is that your opinion is not based on any reasonable evidence so there is no basis for anyone else to be interested in what you think.

    "It is easy for everyone on here to talk about 'scientific evidence' when your view is the evidence of an army of climate scientists. Given that there is a distinct absence of investigation into the merits or not of climate science it will always be a one sided debate."

    As far as I can see all this statement means is that you dont believe the evidence therefore you must conclude that somehow the evidence is flawed, rather than question the basis by which you came to your own opinion instead. You are agreeing there is no evidence to support your view but you hold to that believe anyway?

    In fact, the army of scientists is constant investigating the merits of the science - one positive that came out of the climategate leaks is the robust nature of climate debate between climate scientists. If there is one group of people that have scientists, funding, resources and particularly the motivation to attack climate science, then it is the fossil fuel industry. Instead of doing the science they instead spend their money on disinformation. Why is that? Well because their own scientists tell them the science is solid so it would be a waste of money. This is my industry. I dont know of a single climate denier among colleague in my department.

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

    " The climate has changed before and no-one truly understands it,"

    Except of course that the current climate theory has no problem explaining past change. The problems with past climate change is that, depending on how far back you go, there are multiple possible explanation, all consistent with modern climate theory that can account for the observation. The problem is that is not easy to extract both accurate records for past climate and accurate forcings. However, as the IPCC chapter on paleoclimate shows, theory accounts very adequately for observation given those constraints. "nobody truly understands it" is simply willful ignorance and wishful thinking.

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

    Elephant #36. You waxed philosophical and weren't moderated. Here goes. As I move rapidly to my Final Rewards I'd like to think our bunch can strain enough against its natural powerful purpose, to provide sacks of flesh to aimlessly carry its genes around and do their bidding slavishly, to advance even to proper space ships (which we ain't gonna do by burning rotted vegetables). You have one foot assisting the 3-month time horizon of the fossil-fuel Corporate kings and the other foot planted firmly in the future when our sun blinks out, but you missed the potential fun stuff for future humans in-between. I'm for the fun thing of new ideas, innovation and whatnot, rather than the miserable philosophy you have of <paraphrasing> species come,  species go, so what, that I first heard on a David Suzuki CBC phone-in 15 years ago. I wonder who is with me and who is with you.

  15. Ocean In Critical State from Cumulative Impacts

    The article is a bit hysterical and becomes misleading as biases are intermingled with facts and hypothesis.

    For example: "Ensure effective implementation of community- and ecosystem-based management, favoring small-scale fisheries." implies that small-scale fisheries can't be/ aren't as destructive as "large scale" fisheries. This is a bias not supported by facts. The US gulf coast shrimp trawlers (small boats) clear cut almost the entire gulf every year and put ten times more phosphorous back into the water column than is contributed by the Mississippi River and all the upstream runoff and sewerage from the central part of the US. This impacts eutrophication and the hypoxic zone formation.

    Concepts like: "Build a global infrastructure for high seas governance that is fit-for-purpose" have to face the observational reality described in Public Choice theory that the behavior of that "global infrastructure" will be in the organizations self-interest. The problem is not "building the infrastructure", but designing such infrastructure in such a way that its organizational and individual self-interest aligns with the interest of the planet and humanity. In setting up such a structure, existing fishing interests will be well represented and they will create governance structures to prevent competition from unrepresented future "innovation" in offshore open ocean aquaculture that would put them out of business. 

  16. Levitus et al. Find Global Warming Continues to Heat the Oceans

    Eric (skeptic) - Again, I would refer you to the actual literature, Levitus et al 2012, and the appendix on error calculation. 

    They describe in considerable detail their use of irregularly sampled temperature measurements and resampling down to 1 degree fields - and in their analysis they discuss the standard deviation of temperatures over distance:

    "...showing supplemental Figures S12 and S13 which are maps of the number of temperature observations and standard deviation of all temperature observations used in this study at 700m depth (from Locarnini et al. [2010]). Figures S14 and S15 show the same statistics for 1750m depth. Examination of maps of the standard deviation demonstrate that this statistic is relatively homogenous and isotropic on the data averaging scales we use in our objective analyses for most of the world ocean." (emphasis added)

    Your concern would be valid only if there was sufficient short range variation in temperature anomaly, sufficient non-uniformity, to make the measurements unusable - and as Levitus et al have noted, that is not the case. Temperature anomaly data is sufficiently homogenous for irregular and relatively sparse sampling to track, and the uncertainties involved are part and parcel of their error bars. 

    Keep in mind that, like in atmospheric temperature anomalies (Hansen & Lebedeff 1987, while temperatures may vary over short spatial scales oceanic temperature anomalies have a far stronger correlation over distance. Lacking evidence contradicting the Levitus error calculations (and while you have expressed concerns, you have not presented either data or references supporting such), I would consider their data valid. 

     

  17. Eric (skeptic) at 01:08 AM on 14 October 2013
    Levitus et al. Find Global Warming Continues to Heat the Oceans

    KR and Dave123, thanks for the replies.  I had read a website a few months ago that explained the way Levitus et all assimilated the ARGO data into their climate model.  Basically the model would predict temperatures, they would compare those to the real temperature measurements, then adjust the model for a better fit in an iterative process.  The key point is that the model provided the energy change results not the measurements directly.  When I find that website again, I will read through it and post what I find here.

    I read through the appendix of Levitus et al 2012 and saw a process for estimating the error of a data smoothing algorithm.  I'm not sure how I can evaluate that yet.

    The crux of the issue is determining how much heat has percolated into the deeper ocean.  KR, do you mean that the "mass effect" allows the integration of many estimates of heat transfer to determine an aggregate heat transfer over large regions?  That's true as long as the factors and effects are somewhat uniform. I'm not sure that is true in cases where both heat transfer and heat accumulation vary over relatively small regions.  Nonuniformity seems to be the case looking at figures S5 (which  is averaged longitudinally) and S6 (which is not).

    And Dave123, a linear regression through data points will only work if there is a somewhat linear rise (or fall) in temperature.  That's true for some basins to some extent and true for the world, but is only true sometimes for individual floats.  A higher variance in any particular float means a higher standard deviation and uncertainty.

    But as I said above, I owe you a better answer once I find the web site (it was not a paper, but a NOAA website describing the assimilation process). 

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

    Jubble @54.
    If there is some theory that stands up to scrutiny which would relegate AGW to a non-threatening phenomenon as the contrarians insist, it is a simple question to ask - What is this theory? Do pray tell. I would not be alone in giving any serious suggestion the time of day. And the 3% climatologists who publish papers that do not fit the consensus - they are not very prolific so identifying such a theory shouldn't be too much of an ask as there is little enough literature in which such a theory can be hiding.

    But I don't hold my breath. The whole reason d'etre of this post is that such a theory does not exist. To the great unwashed, the contrarian "side" may appear the same as the scientific "side" but that similarity is an illusion promoted by contrarians and denialists. Scientifically, the difference is that the contrarians continually deny the veracity of whole swathes of science for no other reason than such science is inconvenient for their theorising.

    If the IPCC establish a 95% certainty that human influence has been the dominant cause of rising temperatures over the last 60 years, that does not mean the likes of Elephant In The Room can assume the remaining 5% is his to do with as he will, like some five quid note found lying on the pavement.
    If positive human forcings have been overestimated a bit and/or the negative ones & natural ones & the temperature rise underestimated a bit and the climate wobbles proved to be on the larger side, that presents a situation that would take up the lion's share of the 5%. So all there is lying on the pavement for contrarians to pick up is a bent penny piece. The remaining uncetrtainty gives no scope to deny AGW.

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

    Good article: Can you add Einstein to list of scientist as he showed that the geometry you choose is determing what physics you can measure? And for the Dutch: J.C. Lely, as designer and implementor of one of the biggest waterworks. Both had to wait and sit for 20 years before they were heard. Both had a lot of trouble getting their ideas across. Both needed a 'crisis' to get through the fog of 'common sense' beliefs from vested interest.     

  20. Andrew Mclaren at 22:41 PM on 13 October 2013
    2013 SkS Weekly News Roundup #41B

    As per the lead for the first article, methane offgassing from formerly frozen permafrost layers is a huge concern, but I was given to understand that it is mainly due to bacterial decomposition of organic material following the melt, rather than being spontaneously released from suspension (as with subsea methane clathrates). 

    Maybe I am nitpicking but the phrase "[Permafrost melt] also releases vast amounts of heat-trapping greenhouse gases" might be better qualified as 'indirectly releases'. Although the quantities involved are definitely massive.

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

    MA Roger @49: You may be right and it would be powerful to be able to say that there is no peer-reviewed scientific evidence that refutes AGW that hasn't since been found to be incorrect.  The point I was trying to make was that to a non-specialist both sides of the debate can look the same, as described by Elephant in the Room @50.

    Elephant in the Room @50: I'd be very interested in continuing the discussion with you as you make exactly the point I made in @43 - that both sides of the debate appear the same, meaning you need to make up your own mind what to believe.

    The main counter-AGW argument appears to be: The climate has changed before and no-one truly understands it, therefore there may be some other explanation of the current changes than anthropogenic that is not accounted for in the climate science and the models.  

    The IPCC would actually agree with that I think and put the chance that some other explanation is the dominant cause at 5%.

    Do you think there is a chance that they are right?

    For sake of argument, lets say that humanity is the dominant cause of climate change since 1950, but we don't yet know that it is for certain at the moment.  There would be a lot of scientists trying to find out, wouldn't there?  And most of the scientific results they came up with would support the currently unknown scientific truth, wouldn't it?

    The alternative hypothesis is that humanity is not the dominant cause, and we don't know that for certain at the moment.  In that situation, you would expect a lot of the science to support the view that humanity is not the dominant cause.  That not being the case, you would need to account for the 97% pro-AGW; 3% anti-AGW balance - the counter-consensus argument: there is a large scale confirmation bias among climate scientists, who are looking for evidence for their pre-conceived notions.  You would need to conclude that climate scientists are all bad at their job, or are corrupt in some way.  That seems incredible to me - if it were the case, surely there would be a few good climate scientists out there finding the evidence that refuted AGW?  More than a few?

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

    This is my response to the post by Elephant In The Room (#36).

    "As for scientific explanation - you seem to be laying down the gauntlet for people to refute with scientific evidence something that is currently theory".

    To be clear, I am insisting that the only way to challenge science is with better science. Opinions need to be validated, else they remain mere opinion – and as we’ll see, opinions do not – indeed cannot – add to our scientific knowledge. Only science itself does that.

    The threat of man-made climate change is a theory that currently the IPCC have a 95 percent certainty in (previously 90 percent). It's all semantics.

    No, it’s all statistics. The fact you confuse the two is revealing. (It reveals an agenda, to forestall the obvious question).

    100 percent, 90, 50. It is immaterial. We could all quote our 'out of 10' view on any given subject. It DOES NOT add weight to the argument.

    Nor does TYPING IN CAPITALS.

    Probability is hardly immaterial. Again, your comment reveals an agenda, a lack of understanding, or a refusal to do so. In short, inferential or observational science (where results cannot be tested against a ‘control’ Earth, for example) often relies on a statistical determination. Confidence levels are crucial to understanding the uncertainties, evaluating them, and how they are resolved.

    However, it is my belief, and it is a belief, that the effect of the Co2 that we as humans churn out is minimal compared to the amount produced through natural variation.

    Well, that’s true in a broad sense, (although it isn't natural variation that causes the effect - natural variation is a description of how the effect changes over time. Your misapplication of the term is also part of the sub-text of my article).

    Anyway, the pre-industrial greenhouse effect warms us by around 30 degrees C. Human contributions have added 0.8 degrees C. But since the system is non-linear, and highly reactive, it is a small increase that concerns us because its effect may have consequences far in excess of its proportion.

    To ask a person or persons to refute 'evidence' with 'science' is ludicrous in the same way that it would have been to ask people to challenge that the world was once deemed to be flat.

    This is a serious failure of logic, if you don’t mind me saying so. How else can one challenge scientific evidence, except with better scientific evidence? And your analogy is inappropriate. The belief that the world was flat – not widely held at any time since Ptolemy, by the way – was not a scientific view, but after the birth of Christ, largely a religious one. The appropriate analogy would be to suggest it would be ‘ludicrous’ to challenge the round Earth evidence by citing a religious belief that it wasn’t – exactly the point I made in the article.

    And I can assure you that our brief incursion here will have no effect on the long term future.

    And I can assure you that you have no way at all of knowing that. Your assurances are not remotely credible, since like the rest of us, you cannot predict the future. Attempts to do so smack of superstition, however.

    Are we complaining that we are returning [carbon] to the air after it had once been sequested?

    No, we are concerned about the speed at which we’re doing it, and the warming it's causing.

    Are we complaining about sea levels when we know full well that this is a natural event that occurs post Ice Epoch?

    No, we are concerned that the sea level will rise so fast we will not be able to adapt, and that massive amounts of damage will be done to fragile systems, including the human economy. (By the way, describing these issues as 'complaints' is tone-trolling. They are not complaints, and your attempts to dismiss them as such are more products of an agenda).

    Is it the planets fault that we as humans choose to build houses in coastal areas that will as history tells us become inundated again with water?

    Is it the Bangladeshi’s fault they live in Bangladesh? The Dutch in Holland? That mankind has settled along river deltas like the Indus, Ganges etc because the plains were fertile, and the rivers promoted transport, trade and exchange of ideas?

    Take a good look; there is enough history there to tell you what has been and what will be again.

    In other words, we’ll repeat history because we can’t learn from it. How fatalistic (and also a non-sequitur).

    Do you really wish to throw all your eggs in one basket for the sake of a global threat that isn't really a threat at all? [my emphasis]

    This closing remark serves to make the key point I raised in my article. You claim climate change ‘isn’t really a threat at all’.

    To which I say this: since you can't possibly know this - it's another claim to be able to read the future - in fact that’s just your opinion. To convince me, you’ll have to demonstrate a high probability for the claim – and you can’t. For that, you need science, and you don't have any.

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

    Yes, you do need to supply the details.  And you need to get to know the site.  Your argument has already been dealt with here:

    http://www.skepticalscience.com/co2-higher-in-past.htm

    Not referring to this indicates you're not really interested in much of anything but stopping discussion with 'gotcha's that work in your local pub.

  24. Elephant In The Room at 19:41 PM on 13 October 2013
    Why climate change contrarians owe us a (scientific) explanation

    Comments Policy

    No ad hominem attacks. Personally attacking other users gets us no closer to understanding the science. For example, comments containing the words 'religion' and 'conspiracy' tend to get moderated. Comments using labels like 'alarmist' and 'denier' as derogatory terms are usually skating on thin ice.

    Note: denier, contrarian and alarmist all used in the post by gpwayne . Or do the rules only apply to people that question the science? Just asking a valid  question here?

     

     

    Moderator Response:

    [PW] Moderation complaints/whining noted; move on to the topic of the thread. If you have solid scientific backup for your previously-unsupported assertionss, provide them. Otherwise, further detractive commentary *will* be moderated.

  25. Levitus et al. Find Global Warming Continues to Heat the Oceans

    Eric- So what you've said is that after I pointed out some gaps, you went back and tried to fix it.  That's good. If you truly aspire to be a compelling sceptic, you need to do this first, not as an afterthought.  And I'd suggest you should assume that the people writing those papers have done so.  Peer reviewers tend to be a little reactive when they see a paper than hasn't properly acknowledged prior work in a field.  It's one of the easiest things to 'ding' a paper for.

    Let me add one other point about accuracy that you seem to have missed and KR didn't discuss.  We are interested in the change of temperature in the deep oceans.  Thus the standard procedure of computing the temperature anamoly for each device and working range applies.  A given Argo Float measures a hypothetical temperature of 8.023 C at a depth of 1500 meters. The measurement is repeated on a regular basis of 5 years.  You can run a regression line through the temperatures, which does much the same thing as taking the average of all the temperatures and substracting that average from each data point.  Now you have the anamolies, and those are independent of whether the "true" temperature was 8.021 or 8.025.  If a given thermocouple reads a little high, it always reads a little high.  For a narrow (or not so narrow) range of temperatures you can treat that error as a constant offset.  Looking at the anomoly also allows us to pool data across multiple floats and thus create a statistic that represents the total ocean heat content change.

    Add this to the law of large numbers and you get a statistically sound measurement of an increase in heat going into the lower depths. 

     

     

  26. Elephant In The Room at 19:22 PM on 13 October 2013
    Why climate change contrarians owe us a (scientific) explanation

    @dave 123 (#37)

    Responsibility for details. I don't need to duplicate countless graphs on here to demonstrate our previous relationship with Co2. Now, if you want to tell me that the average global temperature isn't 22 degrees or that the current level of Co2 isn't the lowest it has been for 1 of 3 periods over the last 650 million years then I suppose I should go and find a graph for it. Do you really want me to do that?

    This thread is asking 'contrarians' to provide scientific evidence that something doesn't exist when there isn't irrefutible evidence that it does. There is more credibility in referring to (if that's not sufficient) our previous temperature record.

    We as humans are destroying this planet and everything else that lives on it. We cannot feed ourselves as it is. 10 percent of children in the UK for example live in poverty. We also cannot provide our current energy needs. Carbon dioxide emmissions follow from that because we currently need to and have to burn fossil fuels. There is no escaping it. I would rather Co2 wasn't coughed up into the atmosphere but that isn't going to happen. Furthermore I don't believe the net effect is as great as is being suggested. I am entitled to that opinion and that is what I say.

    It is easy for everyone on here to talk about 'scientific evidence' when your view is the evidence of an army of climate scientists. Given that there is a distinct absence of investigation into the merits or not of climate science it will always be a one sided debate. If by association that makes you right and me wrong then it is very sad state of affairs indeed as let's be honest the view of the IPCC has just upped its belief to 95 percent from 90 percent. While there is still that uncertainty people shall continue to question the a science.

    I am posting on a website that clearly supports the view that man made climate change is occurring. In the same way, if I had argued for man made climate change on a site that refutes man made climate change I would expect the same reaction. And here lies the problem. This is why there will never been any agreement.

    Can the moderators just clarify the posting rules. Is it a rule that you must provide a graph every time you want to question a given subject? It seems that I am receiving quite a bit of back lash for sharing my opinion on a subject matter?

    Also, would calling someone a tone troll also be an example of an ad hominen remark?

    Not a very friendly welcome I have to say. I wasn't rude to anyone was I? Or does offering alternative views automatically make you a troll. (-snip-)

     

    Moderator Response:

    [DB] "Is it a rule that you must provide a graph every time you want to question a given subject? It seems that I am receiving quite a bit of back lash for sharing my opinion on a subject matter?"

    This venue is based in the scienctific method and discusses the science of climate change, from the standpoint of what the primary literature has to say about it.  Every article here at SkS references the primary literature via hyperlinked text.  Discussion in the comment threads is based on increasing the level of understanding of that science, hence the participation of subject matter experts and other talented individuals.

    You will find that opinions are welcome here, but opinions that differ from the primary literature not themselves based on peer-reviewed articles themselves appearing in the primary literature are essentially caterwauling.  And will then be treated as such.  Repetitious behavior in this regard contravenes the "No Sloganeering" portion of the Comments Policy; which, based on your subsequent comment you have indeed read. 

    Future comments by you will be held to adherence to that policy with increasing rigor.

    "would calling someone a tone troll also be an example of an ad hominen remark"

    That would depend upon the context used.  If used verbatim as delineated by you, likely so.  Please provide a link to the specific instance you denote.  Generally, ad hominem refers to "to the man" instead of to the argumentation used by the person.  To call someone's behavior and comments an example of tone trolling might be unhelpful in improving the dialogue, but is not ad hominem.

    Tone trolling snipped.

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

    Jubble @43.

    I would strongly disagree with your statement that "there isn't as much genuine science to refer to" within the theorising on a contrarian site. I would suggest that on such sites there is actually no genuine science to refer to whatsoever.
    It is of course possible to point to scientific papers that appear to fit the bill. As an example of these, Wyatt's "Stadium Wave" hypothesis was referred to @18. But will this "Stadium Wave" hypothesis stand up to proper scrutiny? As I am a little familiar with the profiles of PDO & AMO before they have been converted into pretty harmonic waves, and also the post-2000 data, my answer is a definite "No it will not!"
    Because absolutely none of the hypotheses or analyses paraded on contrarian sites stand up to proper scrutiny, with such an asymmetry, how can this be a debate with two sides? It is not. It is better characterised as 'one side' refusing to accept the evidence presented by the other but unable to provide a reasonable argument for such a refusal.

    It would be good if there were a "third way" to address this impass but tackling AGW is not a straightforward task. (If it were, we would just tackle it, like we did CFCs.) Tackling AGW is going to require changes that many will not immediately consider desirable. So if you don't see AGW is a problem, you will resist such change rather than support it. And a large section of the public, of the media, of our politicians are still unable to see AGW as a problem. (An example of such change and resistance, local to me, planting 175 sq km of sea with wind turbines 20 km off shore has turned the county into a hot-bed of NIMBYs. To them cutting carbon emissions by 750KtC, equal to half the county's total carbon footprint, that counts for nothing.)

    This post argues that contrarians owe the world a genuine scientific explanation. To date they have presented no "genuine science" but instead make fools of the world by continually presenting forgeries.
    If you cannot make good a debt you owe, you can be declared bankrupt. I think the time is long overdue that contrarians are declared bankrupt. And that is why I brand them deniers.

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

    Stealth - "I’m just curious, what is your background?"

    An Argument from Authority is a logical fallacy - it's the strength of the evidence and argument that matters, not the credentials of the person presenting a position. And regardless of your background, you have not supported your posts

  29. Levitus et al. Find Global Warming Continues to Heat the Oceans

    Eric (skeptic) - There are, quite frankly, a number of misconceptions present in your last post. 

    "The latter paper also notes that the accuracy of temperature measurement was 0.002C so measuring a 0.002C change is problematic." - Incorrect. You seem not to understand how the margin of error changes with multiple measurements, the law of large numbers. Measurement error decreases with the number of samples, with the rough proportion of 1/sqrt(n). The uncertainty of a single measurement is a vast overstatement of the uncertainty of multple measurements. 

    WRT to sampling grid size, regardless of whether or not the sample spacing is fine enough to resolve individual 'salt fingers', the mass effect of heat transfer is quite measureable. And that holds whether or not the phenomena driving the mass transfer of energy is below the scale requiring parameterization in a model - if it has a significant effect, that will show up in the larger scale measurements. 

    The core of your post, however, appears to be a claim that there are inaccuracies not accounted for in Levitus et al and the literature in general, inaccuracies sufficient to invalidate the presented data. I would strongly suggest you actually read Levitus et al 2012, in particular the appendix labeled "Error Estimates of Objectively Analyzed Oceanographic Data", and if you have any serious objections to their methods point them out. Otherwise, you are simply making vague and unsupported insinuations of inaccuracies without evidence - and such statements without evidence can in turn be dismissed without evidence. 

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

    "You cannot have accurate long term forecasts and inaccurate short term forecasts."

    Um, I can forecast the average temperature for the month of May next year I suspect with greater accuracy than I can predict the average daily temperature for Sunday week times That is rather like the difference between weather and climate.

    As to background -  I program models for, among other things, thermal evolution of sedimentary basins and in particular the evolution of hydrocarbon geochemistry over time. This is to answer the questions like "does this basin produce hydrocarbons, and if so, when, how much and in what phases". More than most however, the problem is dominated by uncertainty and poor constraints.

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

    Stealth does not appear to understand the difference between boundary and initial value problems

    Consider as an example Los Angeles freeway traffic. Predicting exact volume even a few hours from now (initial value problem) would require exact numbers of cars on the road, perhaps some estimates of how aggressively they are being driven, detailed road conditions, etc. From that you could make detailed and relatively exact projections of how traffic might behave a few hours later. But not for a week down the line - there's too much that can occur in the meantime. 

    If, however, you wish to make long term projections of what traffic might be (boundary value problem) - given  information on population, predictions on neighborhood growth, planned on/off ramp construction, and perhaps the football schedule (for near-stadium effects), you can make an average traffic prediction years down the road. You won't be able to predict the exact number of cars passing a point on the road on a particular Tuesday five years ahead - but you can make excellent predictions of the averages. And in fact city planners do this all the time. 

    In terms of evaluating climate models, whose mean trends are a boundary value solution - the climate has many short term variations, and it is only to be expected that short term variations will indeed occur around energy bounded long term trends. Models are quite frankly doing very well right now:

    RealClimate model/observation comparison 2012

    [Source]

    In order for the models to be invalidated by observations, the long term trend would have to go beyond the boundaries - far enough that such a new trend +/- the range of variation departed from the model predictions +/- variations. That hasn't happened, not by a long shot - and (IMO) it won't, as we have a pretty good handle on the physics. 

    In the meantime, demanding impossible perfection from boundary condition models, in the presence of short term initial value variations, is just a logical fallacy. 

  32. SkS social experiment: using comment ratings to help moderation

    I think it would be a good idea to have a third option, maybe a grey thumb pointing sideways and would mean skeptical. And providing a dropdow of the voters names when you move your mouse over a icon may stop gaming and trolling

  33. Eric (skeptic) at 12:15 PM on 13 October 2013
    Why climate change contrarians owe us a (scientific) explanation

    Dave123, thanks for the critique.  The core of my alternative explanation follows after I comment on the ocean-has-missing-heat theory.  Obviously my critique of Levitus deserves a more thorough explanation which is here

  34. Eric (skeptic) at 12:14 PM on 13 October 2013
    Levitus et al. Find Global Warming Continues to Heat the Oceans

    In this thread I posted a link to Schmitt et al 2005 and stated that "The bottom line is we don't really know how much 'missing' atmospheric heat has wound up in the oceans."  Dave123 replied that "the paper makes the case that mixing was faster than anticipated" and quoted form the paper here.  He suggested checking cites so I did, although not all 71 of them.  Searching within the cites for GCM was dry, but searching for ARGO brought up this paper: website: scientiamarina.revistas.csic.es path: /index.php/scientiamarina/article/viewFile/1384/1488 that suggests that the Schmitt results were localized that were not present in the rest of their Atlantic ocean cross section.  I didn't pursue the cites further.

    But more apropos is the Levitus papers themselves such as this one: World ocean heat content and thermosteric sea level change (0–2000 m), 1955–2010  In order to fill in missing data for the 700-2000m depth they have to model how much heat flows down from the 0-700 depth which has good coverage.  The relatively small temperature changes that SASM asks about in post 28 is answered by Tom two posts later as being 0.1C over the period.  However the annual energy change is roughly 1022 Joules so the temperature change for 6 x 1023 cubic cm of seawater with 4 J/g/C is 0.002C per year.

    The answer to KR's reply a few posts later that the large number of sample points reduces the error: there are only 4 data points in each one degree grid square in the model in Levitus.  The mixing shown in the Schmitt paper and the other paper linked above requires simulation at the 1 degree cell resolution to simulate the mixing processes.

    The latter paper also notes that the accuracy of temperature measurement was 0.002C  so measuring a 0.002C change is problematic.  Also the ARGO network has about 3 degree spacing according to their website which makes it basically impossible to simulate the mixing, so it must be parameterized.

  35. Ocean In Critical State from Cumulative Impacts

    There is an additional threat to our oceans and that is the slowly increasing levels of mercury and other heavy metals. Heavy metals have been locked up (and away) for eons in coal reserves and when coal is burned, they aerosolise. Large amounts eventually settle in our oceans, are absorbed by biota such as algae and eventually make it up the food chain on to your dinner plate. Hence the limits on eating palargic fish such as sword fish no more than once a week. A recent three year study measuring tissue levels of heavy metals in 500 whales found alarmingly high levels. The study surmised that this was directly linked to a fall in whale fertility. and this would likely doom most whale populations within 100 years.

    Yet another reason to leave coal in the ground. Thankfully many countries have excellent plans showing a switch to 100% renewables is entirely possible within 10 years. (See Beyondzeroemmissions). 

  36. Bert from Eltham at 10:31 AM on 13 October 2013
    Why climate change contrarians owe us a (scientific) explanation

    Jubble this 'third way' you speak of used to be peer reviewed science. That is evidence based knowledge from experts in their field to influence the policy makers such as our political institutions and business leaders. This has been paralysed by very dark forces that continually throw doubt on the peer reviewed scientific evidence. This is in a time where the peanut gallery is a worldwide phenomena due to the web. This peanut gallery is louder than the worlds experts. They do not have to win arguments with any logic or evidence. Just put up a constant noise to drown out the message that they disagree with.

    I am sure that that these dark forces are somehow also exploiting a form of Poe's Law where the pseudo scientific sites on Global Warming are indistinguishable from the real scientific sites to the average layman. Bert

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

    Eric, your citation of Schmitt (2005) puzzles me.  First, the paper makes the case that mixing was faster than anticipated.  

    The significant vertical dispersion of tracer observed in this thermohaline staircase supports the idea that salt fingers significantly enhance mixing in certain parts of the main thermocline. Our derived salt diffusivity of 0.8j0.9 10j4 m2/s is an order of magnitude larger than that predicted for typical internal wave breaking within the mid-latitude thermocline. Indeed, for this low-latitude region, parameterization of mixing supported by the background internal wave field (32, 33) indicates that a diffusivity of only È0.02  10j4 m2/s should be expected. The tracer derived
    diffusivity is also larger than that implied by microstructure measurements previously
    made in this staircase (16, 25, 34). However, it is in agreement with the salt finger
    model applied to those dissipation data (35), as well as to our new observations. Notably, the diapycnal tracer mixing rate observed in the western tropical Atlantic is 5 times that observed in the eastern subtropical Atlantic during NATRE, because of the presence of the thermohaline staircase. The staircase appears to transform the T-S structure of the thermocline waters entering the Caribbean, increasing the salinity and density of Antarctic Intermediate Water (36) and preconditioning it for sinking at higher latitudes.  The efficient vertical transport within this strong tropical thermocline must be taken into account in oceanic and climate models, where the parameterization of diapycnal mixing continues to be a major uncertainty in assessing the ocean's ability tosequester heat, pollutants, and carbon dioxide.

    In otherwords, I don't think the paper can be read the way you're claiming.  Beyond that, this paper is 8 years old.  Did you do any work to check citations.  If this were a class paper, I'd certainly demand evidence that you'd followed the scholarly trail and were presenting an opinion grounded on more than one paper.  What work has been done since.

    Then there's this question.  There's instrumental data from the Argo floats.  You've made no mention of this, only models.  Why not?  If you don't like the data, wouldn't your exposition be sounder if you brought this up and disposed of it?

    If you want to create a synthesis, you need to do the work.  Especially here, where the aggregate of people do follow the literature, check citations, and routinely attempt sound scholarly syntheses.  Unless of course, you think picking a few papers is "good enough for a 'C'", in which case you'll not convince anyone here.

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

    Stealth, you wrote:

    I have noticed that no one has answered the question of their background. This leads me to speculate that you are unqualified to discuss software modeling and accuracy.

    This and similar comments, along with your login name, appear to be attempts to pull rank by virtue of your software 'expertise'.

    In fact, programming software is fairly easy for anyone with a basic sense of syntax and logic. The difficulty with software modelling is not really in the writing of the code, but in understanding the domain you are trying to model. You clearly have very little knowledge of the climate domain, and you seem resistant to the patient attempts of others to educate you.

    You also wrote:

    You cannot have accurate long term forecasts and inaccurate short term forecasts.

    This patently false comment reveals that you do not understand - even in the broadest terms - what the models are trying to achieve and how they relate to the real world, perhaps because you are drawing faulty analogies with the one domain you do understand (aviation modelling). There are countless situations where long-term projections are possible despite short-term unpredictability.

    For instance:

    • A hose is running into a half-empty backyard swimming pool at a constant rate. People are splashing about in the pool, so the water level near a monitor fluctuates wildly, but the rise is linear in the long term. (This example from some other SkS poster.)
    • Snow depth on a mountain increases in fits and starts during winter, and melts off in spring. The general rise and fall in snow depth over months is predictable, despite the poor predictability over days.
    • A professional poker player sits down with a novice. The hands and flow of money are totally unpredictable in the short term, but we know who is going to win by the end of the evening.

     

    Some systems are highly divergent, and small-short term effects propagate to create vastly different outcomes, like the proverbial butterfly flap. But others are highly convergent, and small short-term effects are swallowed up. This is particularly the case for climate modelling, when many of the short-term effects are merely moving heat around within the system, without substantially changing the cumulative and predictable heat imbalance due to GHGs.

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

     ANYWAY,   i meant

    Moderator Response:

    [PW] Extraneous characters trimmed off.

    Thanks for the kind words: As many have stated, moderation is a arduous and thankless job, and the commission of good, focused moderation is the hallmark of an excellent website. DB, JH, Ari, and JC himself, just to mention a  few, do yeoman work in making the place consistently good.

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

    I'm going to slip in a plug for the moderation hereabout, though it may be "offtopic".

    Whomever is doing it, it is outstanding.  To keep up with all the arcane "facts", their sources, tone, effect, and intent:  and the personas behind the sometimes sniping egos whose argumentation is occassionally specious..

    and provide a net effect of lucid edification for those who seek education..

    constitutes a great service.

     

    Sometimes when I encounter a self righteous "denier", I send them here to hoist their petard, and get it trimmed.

    ==============

     

    WTHell:  what if it was "natural fluctuation" ( which it ain't):

    if the biosphere is dying, we are all that CAN respond to support  it.

    =============

    We WILL get around to "direct air capture" eventually.

    ============

     

    Anywya, Good Work" moderator(s)!

     

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

    Why climate alarmists owe us a (scientific) explanation

    For a while now, I’ve considered AGW to be akin to superstition, which the Oxford Dictionaries site defines as “a widely held but irrational belief in supernatural influences.” I mention this because when challenged, alarmists often claim that the climate changes we are witnessing are not due to natural variability, but products of humanity. In this context, I find that 'humanity' appears to be a synonym for ‘supernatural influence’.

    Why? Because they can’t explain it. Not just that: many seem to believe they are not obliged to do so, which is suspiciously convenient, and all too reminiscent of those who would claim they don’t need to ‘explain’ God. In this, they share a view once expressed in a Daily Mail forum which, to this day, remains one of my favourite alarmist non-sequiturs. When challenged, a poster calling himself Romeo 4 insisted “I don’t need to prove climate change is caused by humanity. It just is.”

    ....

    The above could easily be the start of a blog post on WUWT or some other denial blog.  The point I am making here is that to someone who has not read extensively through the science with objectivity, it is very difficult to tell the difference and therefore it is very easy for confirmation bias to occur.

    The only difference would be that in a denial site there are fewer papers from which to choose, and more of the references would have to be to non-peer reviewed literature, because there isn't as much genuine science to which to refer.  That issue is easily dismissed by asserting that consensus science is not science at all - you can imagine a scientific consensus building up where in fact the truth lay in the minority view.

    As long as both sides of the debate look the same it will be difficult for the changes in attitude needed to cope with climate change to happen.

    What is needed is a "third way" - a way to avoid the constant to and fro wrangling; to find a different direction that takes everyone with it, rather than entrenching views.

    Could that be business realising that it is better to mitigate than adapt?  Could it be demonstrating the benefits of change rather than the reason for those changes?  Could it be discussion and quantification of risk?  Or could it be something else completely?

    Unfortunately I don't know - and I'll stop there to avoid getting off-topic.

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

    Stealth, for even more about initial values versus boundary conditions, see Steve Easterbrook's post.  While you're at it, go to RealClimate's Index, scroll down to the section "Climate Modelling," and read all of the posts listed there. For example, in the post "Is Climate Modelling Science?", there appears: 

    "I use the term validating not in the sense of ‘proving true’ (an impossibility), but in the sense of ‘being good enough to be useful’). In essence, the validation must be done for the whole system if we are to have any confidence in the predictions about the whole system in the future. This validation is what most climate modellers spend almost all their time doing."

    For the umpteenth time:  You need to read the Skeptical Science post "How Reliable Are Climate Models?", including both the Basic and the Advanced tabs.

    For a broader and deeper discussion of how climate models are verified and validated (V&Ved), read software professor and former NASA software quality assurance guy Steve Easterbrook's explanation.

    A good, short, essay on the role of computer models in science is in the journal Communications of the ACM, the September 2010 issue, page 5: Science Has Only Two Legs.

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

    Yes Stealth, your attempt to "not be a jerk" is failing.  You are vastly overestimating the breadth of your knowledge by making such ridiculous assertions as "That is hogwash. You cannot have accurate long term forecasts and inaccurate short term forecasts,"  when that has been explained to you over and over and over for weeks (months?).  Once more, for an explanation see "The Difference Between Weather and Climate."  For even more, see "Chaos Theory and Global Warming: Can Climate Be Predicted?"

    Moderator Response:

    "You are vastly overestimating the breadth of your knowledge by making such ridiculous assertions....when that has been explained to you over and over and over for weeks...."

     

    [PW[ Indeed, and from now on, a newly-coined parameter will be taken into account, when posters do this. It's called 'anterograde amnesia,' and continuing utilization of the technique will be considered obfuscatory, and will be appropriately moderated. Tom Curtis has patiently explained such things to you, Stealth, and you've consistently acted as if the news was...well, new. No more.

  44. StealthAircraftSoftwareModeler at 06:43 AM on 13 October 2013
    Why Curry, McIntyre, and Co. are Still Wrong about IPCC Climate Model Accuracy

    My bad. I asked for some background info and didn't see Tom's post that came in while I was typing. I'm really trying to have a good discussion and not be a jerk denier, because I'm not one. (-snip-). 

    Moderator Response:

    [DB] Sloganeering snipped.  You have been pointed to resources which countermand your position.  Unless you have new evidence, it is time to drop it.

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

    @JRT256 #18 You can do a 1st-order approximation to gain some credibility re "temperature rebound". I'm hoping to find time off work for it myself this Christmas/Festivus. Simply estimate linear trends over a few thousand years of the temperature last 18,000 years, then integrate temperature anomalies using stated ocean heat increases and whatever you can find re ocean current rates & quantities to get this 1st-order approximation of changes in ocean heat content the last 18,000 years. Demonstrate that the last few decades of ocean heat content increase are simply a re-balancing from the few hundred prior years. Good luck.

  46. StealthAircraftSoftwareModeler at 06:09 AM on 13 October 2013
    Why Curry, McIntyre, and Co. are Still Wrong about IPCC Climate Model Accuracy

    (-snip-). That is hogwash. You cannot have accurate long term forecasts and inaccurate short term forecasts.

    Rob @137 and @138: I may not be understanding the “boundary conditions” -- please explain what it is. And for the record I am referencing Tom Curtis’ chart @126. It does not, I believe, have any of the “initial conditions” you mention. The boundary in Tom’s chart @126 seems to be well defined edges of accuracy and unlikely to be crossed. But if it can be crossed and the model still be correct, then what has to happen to determine that the model is inaccurate?

    Moderator Response:

    [DB] Sloganeering snipped.

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

    There are some wonderful examples of denial on this comment thread. Elephant In The Room @36 certainly provides such an example.

    The main thrust of his argument is that natural variation is very large when considered over tens of millions of years. Thus an 8ºC increase in global temperature would do nothing but return the planet to the average temperature for such a time period. And over such timescales CO2 has been measured in parts per thousand rather than the present parts per million so the level of CO2 doubling or quadrupling through the burning of fossil fuels is nothing we should 'complain' about.
    "Humans are a brief visitor to this planet," he boldly tells us (I think he means "inhabitor" rather than "visitor", but whatever.) which presents a very fatalistic view of humanities future but these are large sweeping timescales being discussed. Let's be fatalistic.
    These ideas are presented by Elephant In The Room as "fact" which he tells us cannot be overturned by any "scientific explanation." I am sure many would agree with such argument within its proper place.
    So where is it that Elephant In The Room places this argument?

    It is used to objection to mitigation measures to combat AGW. This is particularly odd as AGW is a phenomenon that will act over decades and centuries, a miniscule timescale compared with the prior items of discussion.
    But that doesn't matter because AGW "is a global threat that isn't really a threat." It seems precipitating an 8ºC global temperature rise that could bring mankind's terestrial "visit" to an end is not "really a threat at all."
    The end of all human existence is not really a threat to humanity? I think Elephant In The Room is suffering denial and sorely needs a reality check.

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

    Please excuse the crudity but you are peeing agains the wind.  Most contrarians wouldn't know a scientific thought if it bit them on the behind.

  49. Eric (skeptic) at 05:05 AM on 13 October 2013
    Why climate change contrarians owe us a (scientific) explanation

    ...the change in energy levels – required to increase the global temperatures rapidly over three decades, to melt glaciers, to warm oceans...

    Referring to this diagram:

    Global heat content

    Glacier melting did and does not use much of the assumed change in energy levels.  The warming oceans are supposed to account for most of the recent lull in the atmospheric temperature rise, but is the heat transfer to the oceans adequately modeled?  This paper http://www.sciencemag.org/content/308/5722/685.full.pdf suggests it is not.  As they say in their conclusion, the mixing described in the paper is a major uncertainty in the parameterization of mixing (in climate models).  The bottom line is we don't really know how much "missing" atmospheric heat has wound up in the oceans.

    Here's a climate model that won't satisfy rader5:

    Lindzen E&E 2007 figure 2

    The key point in the diagram (which is from Lindzen 2007 Energy&Environment) is that the angle of the arrows representing latitudinal heat transfer is a function of parameters, not physics, in all climate models.  But AFAIK, Lindzen has not provided an alternative GCM with his own cherry-picked parameters to make that point.

    Matt Fitzpatrick leaves out of his list (ending with "pirates") the "weather", specifically weather that increases or decreases latitudinal heat transfer.  He probably leaves it out in the belief that it affects the short run and can't explain decades of change.  But I don't think that is completely correct.  I would suggest to Alexandre that a potential "magical negative feedback" is weather insofar as the increased in meridional flow and consequential increased in storminess (neither are true IMO) are supposed to be from Arctic Amplification.  But wouldn't that increase latitudinal heat transfer and slow global warming?

    But Alexandre is correct that we ought not believe "magical negative feedback" until we see some evidence for it.  I believe that long term increases and decreases in meridional flow and latitudinal heat transfer come from long term natural factors, mostly solar. 

    Here's a quantification of meridional heat flux journals.ametsoc.org/doi/pdf/10.1175/JCLI3539.1 (Carl Wunsch: The Total Meridional Heat Flux and Its Oceanic and Atmospheric Partition, 2005) of about 5 PW atmospheric.  Dana's diagram at the top of my post shows about 1022 Joules of increase per year.  5 PW equals about 1023 Joules per year.  Obviously only a small part of the 5 PW is going to be lost to space as Lindzen's simple climate model implies.  But the 5PW and fluctuations in that amount are clearly a factor in earth's energy balance.

    Here's an old paper showing adsabs.harvard.edu/full/1981SoPh...74..399B showing how variations in solar UV could influence climate by changing planetary waves through photochemical changes in the stratosphere.  The lower stratosphere has stopped cooling in the last 15-20 years:

    TLS graph from http://images.remss.com/msu/msu_time_series.html

    (Note: the middle stratosphere is still cooling substantially).  I believe these variations in the lower stratosphere are part of the explanation in the lull.  If I am correct we should see substantial warming in that TLS graph in the coming solar minimum as the high frequency solar UV decreases causing an overall ozone increase causing TLS warming.  The TLS warming is not a direct factor in the meridional heat flux, but it represents strong variations in stratospheric temperature which lead to greater meridional heat flux.

    Here's  a possible explanation of high sensitivity of early 2000's climate models: journals.ametsoc.org/doi/pdf/10.1175/1520-0442(2002)015%3C1659%3AIADVOP%3E2.0.CO%3B2 (Hu: Interannual and Decadal Variations of Planetary Wave Activity, Stratospheric Cooling, and Northern Hemisphere Annular Mode) which notes the stratospheric cooling to that point (paper is from 2001) potentially caused by GHG increases (plus ozone depletion) and asks whether the stratospheric cooling causes or is caused by an increase in NAM (Arctic Oscillation).  (Note that AO has been trending negative since the mid 2000's after this paper was written).

    Essentially high sensitivity in the models up to the early 2000's comes from a stronger polar jet which comes from a cooling stratosphere.   This decreases meridional flow and meridional heat flux and thus enhances global warming.  In more recent models the polar jet is weaker and consequently sensitivity is lower.  Whether Arctic Amplification plays a role in the strength of the polar jet (e.g. as explained by Jennifer Francis and others) is still undetermined.  My preferred theory is that external solar factors control it although the real answer is undoubtedly a mixture of external, internal natural and anthropogenic factors.

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

    Lei: "And the truth is, you would feel far more comfortable sitting at the same dining table with the skeptics who are millionaires, than these poor folks who might steal your wallets."

    Chuckle.  So all poor people are thieves, and no millionaires are thieves.  How medieval of you.  

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