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cloa513 at 00:22 AM on 15 April 2011Christy Crock #3: Internal Variability
Yet according to IPCC models that tiny addition from volcanoes (Kroatoa particularly) should have caused a massive temperature change- the temperature change is barely noticeable. -
cloa513 at 00:20 AM on 15 April 2011Christy Crock #3: Internal Variability
Impossible to post on most other threads. e.g. models are unreliable thread does not accept posts.Moderator Response: The climate models thread absolutely accepts posts, as does every thread on this site. If you would like to discuss climate model reliability in general, you are encouraged to take your discussion there. -
logicman at 00:00 AM on 15 April 2011Monckton Myth #16: Bizarro World Sea Level
Morner's trick: Taken from the WUWT page recommended by daniel. Can you spot the trick, boys and girls?
Note also the use of a stock rhetorical trick: "X was done by unspecified members of group Y". "The Reichstag was burned down by Jews." Pace Godwin and the SkS moderators.
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Arkadiusz Semczyszak at 23:52 PM on 14 April 2011Solar Hockey Stick
Sorry , my fault, A few citations, which recently I put on this site: Sub-Milankovitch solar forcing of past climates: Mid and late Holocene perspectives, Helama et al., 2010.: “The observed variations may have occurred in association with internal climate amplification (likely, thermohaline circulation and El Niño–Southern Oscillation activity). THE NEAR-CENTENNIAL DELAY in climate in responding to sunspots indicates that the Sun's influence on climate arising from the current episode of high sunspot numbers may not yet have manifested itself fully in climate trends. Testing solar forcing of pervasive Holocene climate cycles, Turney et al., 2005. : “The cycles, however, are not coherent with changes in solar activity (both being on the same absolute timescale), indicating that Holocene North Atlantic climate variability at the millennial and centennial scale is not driven by a linear response to changes in solar activity.” Cyclic variation and solar forcing of Holocene climate in the Alaskan subarctic, Hu et al., 2003.: “Our results imply that small variations in solar irradiance induced pronounced cyclic changes in northern high-latitude environments. They also provide evidence that centennial-scale shifts in the Holocene climate were similar between the subpolar regions of the North Atlantic and North Pacific, possibly because of Sun-ocean-climate linkages.” Response of Norwegian Sea temperature to solar forcing since 1000 A.D., Sejrup,2010.: “The correlations are synchronous to within the timescale uncertainties of the ocean and solar proxy records, which vary among the records and in time with a range of about 5–30 years. The observed ocean temperature response is larger than expected based on simple thermodynamic considerations, indicating that there is dynamical response of the high‐latitude ocean to the Sun.” Swingedouwet al., 2010. lag TSI - temperature - 40-50 years - regional NH. The influence of the de Vries (∼200-year) solar cycle on climate variations: Results from the Central Asian Mountains and their global link, Raspopov et al. 2006.: “An appreciable delay in the climate response to the solar signal can occur (up to 150 years). In addition, the sign of the climate response can differ from the solar signal sign. The climate response to long-term solar activity variations (from 10s to 1000s years) manifests itself in different climatic parameters, such as temperature, precipitation and atmospheric and oceanic circulation.” Mid- to Late Holocene climate change: an overview Wanner et al., 2008: „On decadal to multi-century timescales, a worldwide coincidence between solar irradiance minima, tropical volcanic eruptions and decadal to multi-century scale cooling events was not found..” Medieval Climate Anomaly to Little Ice Age transition as simulated by current climate models, González-Rouco et al., 2011.: “Therefore, under both high and low TSI change scenarios, it is possible that the MCA–LIA reconstructed anomalies would have been largely influenced by internal variability. ” Climate change and solar variability: What's new under the sun?, Bard and Frank, 2006.: “Overall, the role of solar activity in climate changes — such as the Quaternary glaciations or the present global warming — remains unproven and most probably represents a second-order effect.” -
Monckton Myth #16: Bizarro World Sea Level
Dikran Marsupial, Moderators - Many of the hyperlinks in this post don't work as formatted; they all have www.skepticalscience.com appended at the beginning.Moderator Response: [Dikran Marsupial] Many thanks, I have fixed them now. -
Daniel Bailey at 23:49 PM on 14 April 2011It's not bad
It's only a negative if you want your beer cold:
Climatologists: "We drink beer because we care"
The Yooper
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poptart at 23:44 PM on 14 April 2011Monckton Myth #16: Bizarro World Sea Level
I believe Lord Monckton is a "peer". Therefore, anything he peruses is "peer reviewed".With that in mind, I bet we can get poptech's list up to 1000! -
Alec Cowan at 23:44 PM on 14 April 2011The e-mail 'scandal' travesty in misquoting Trenberth on
@Ken Lambert #110 Interesting, but no. There are a lot of problems in that argumentation -and in your conclusion-, for instance the down-dwelling being restricted by BP's ukase to polar iceshelves borders. The matter here is quitting the fallacy of the 0-700m layer being "the oceans" and repeating the same analysis for 0-300m layer, 0-500m layer and 0-1000m layer. You also can present the 0-700m layer analysis by sublayers of 100m. Once that done -and it has being done- just observe if all layers follow a similar trend or there are a lot of heat relocations -to avoid the term "transfer"-. The technique of the bullsphere 2.0 has been so far a lidocaine one: just pounding on the outer layer for 2004-2008, trying to keep the previous +10 years in shadows and 75% of the ocean dark as it is, and then, once the anaesthetic effect is obtained, add some wishful thinking disguised as a conclusion, for instance "So not only ..., we might have had little for the 17 years 1993-2010 shown on the charts." Really!? Ah! "we might"! the everlasting use of a modal auxiliary verb as an epistemological resource. -
les at 23:08 PM on 14 April 20112nd law of thermodynamics contradicts greenhouse theory
Fred, congratulations on post No. 1000 - although it may as well be 1000 mod 1. No amount of the written word, nor bean counting, can substitute for some good solid physics. No one has yet given the equations which demonstrates that the introduction of a some particular gas, when placed between two radiating bodies at different temperatures, can cause the 2nd law of thermodynamic to brake down. On the other hand, we have perfectly good illustrative physics models of the target system showing the 2nd law in good shape. Equally we have perfectly good physics models showing how the above arrangement of certain gases can reduce the rate of cooling of body at the lower temperatures. Thus far, the thesis of this blog post holds good. IMHO 1001 posts is more than adequate to establish that! -
Dennis at 23:04 PM on 14 April 2011Monckton Myth #16: Bizarro World Sea Level
"Instead you send me off to read hundreds of pages of scientific analysis." This is how science works, Daniel. Those who choose to present scientific "findings" (such as the WUWT writers) and do not do that have no standing to criticise those who do. Those who do not have the skills or time (and I include myself in this group) to perform such analyses should respect the research of those who have. -
Arkadiusz Semczyszak at 22:59 PM on 14 April 2011Christy Crock #3: Internal Variability
Internal variability ... - let's look into the paper 2010 UKCP09. : „Uncertainties remain in estimates of natural internal climate. Internal variability is difficult to estimate from available observational records since these are influenced by external forcing, and because records are not long enough in the case of instrumental data, or precise enough in the case of proxy reconstructions, to provide complete descriptions of variability on decadal and longer time scales.” Of course you can cite the paper: A Significant Component of Unforced Multidecadal Variability in the Recent Acceleration of Global Warming, DelSole, Tippett and Shukla, 2010. : “While the IMP can contribute significantly to trends for periods of 30 years or less, it cannot account for the 0.8 o C warming trend that has been observed in the twentieth century spatially averaged SST.” However, I would recommend NIPCC comment to this paper: “In considering the latter portion of the record (1946-2008), results indicated that the internal variability component of climate change (the IMP) operated in a cooling mode between 1946 and 1977, but switched to a warming mode thereafter (between 1977 and 2008), suggesting that the IMP is strong enough to overwhelm any anthropogenic signal.” Does the past - the Holocene - we had a strong global changes, that are difficult to explain simply the influence of external factors? Mid-Holocene regional reorganization of climate variability, Wirtz et al. 2009. : “We integrate 130 globally distributed proxy time series to refine the understanding of climate variability during the Holocene.” “Secondly, at most sites, irreversible change occured in the Mid-Holocene. We suggest that altered ocean circulation together with slightly modified coupling intensity between regional climate subsystems around the 5.5 kyr BP event (termination of the African Humid Period) were responsible for the shift.” “It seems likely [comparison n 250, 550, 900 and 1450 yr cycles] that altered ocean circulation together with slightly modified coupling intensity between subsystems (regional interplay of ice, ocean, atmosphere and vegetation) after the 5.5 kyr BP event made these subsystems either more or less prone to oscillations. The discussion of possible mechanisms behind changed climate variability, however, has to be substantiated by future modelling studies.” The same we can said of the MCA - LIA. Medieval Climate Anomaly to Little Ice Age transition as simulated by current climate models, González-Rouco et al., 2011.: “Most models have used relatively high TSI variations from the MCA to the LIA and their pattern of response is typically a uniform warming in the earlier period. In spite of this, there are considerable differences among the simulations that highlight a feasible influence of initial conditions and internal variability. Furthermore, if reduced levels of past TSI are given more credit, as in the MPI-ESM-E1 ensemble, the temperature response for the MCA–LIA is less uniform in sign and visibly more influenced by internal variability. Therefore, under both high and low TSI change scenarios, it is possible that the MCA–LIA reconstructed anomalies would have been largely influenced by INTERNAL VARIABILITY. [...]” -
Alec Cowan at 22:57 PM on 14 April 2011The e-mail 'scandal' travesty in misquoting Trenberth on
@logicman #100 Both, paper and graphic refer to the same ocean layer, not to the whole oceans. As an interesting exercise for students, take some typical ocean temperature profile, for instance, this, and estimate how much you have to move it downwards -repeating the same temperature in the surface- to hide 1023J throughly distributed. You will be surprised by the answer. -
Dikran Marsupial at 22:52 PM on 14 April 2011Christy Crock #3: Internal Variability
Giles: I postulated no such thing, it is purely your own invention. A chaotic system can have more than one attractor, nowhere did I suggest that is not the case of the weather (which means that is is possible natural variability could result in long term changes - e.g. snowball Earth). The primary interest though is in the responses to forcings. If all of the model runs agree on the long term hindcast, that is reasonable grounds to think it is probably forcings, if some fall into one cluster and others fall into another, that would suggest more than one "attractor" (not sure that actually happens though), that would be an indication that it was not only forcings. In both cases, we don't know anything for certain, we just know the consequences of what out current knowledge of suggests is plausible, nothing more. As I have repeatedly said, (paleo)climatologists know that perfectly well. You will notice I used a lot of probabilistic qualifiers in that paragraph, there is a good reason for that, which is that any knowledge we gain from any observation is necessarily uncertain. I can't believe you are still going on about proving a hypothesis to be true. This shows a complete lack of understanding of the philosophy of science, an hypothesis regarding objective reality can never be proven, only disproved. This is central to the writings of Karl Popper, which IIRC you claimed you understood. My reasoning is not circular, the models are used to determine the consequences of a set of assumptions, nothing more. Nobody assumes the models are correct (in fact as GEP Box suggests, we know they are not correct, but that doesn't mean they are not useful). -
Ken Lambert at 22:52 PM on 14 April 2011The e-mail 'scandal' travesty in misquoting Trenberth on
Gilles #105 Your numbers are right Gilles. Dr Trenberth's number for a global imbalance of 0.9W/sq.m is 145E20 Joules/year. The only place this heat can be stored (over 90%) is in the oceans. Therefore the rise in OHC must be the integral of the net forcing (the area under the forcing curve) between time T1 and T2. Check out this thread: http://www.skepticalscience.com/news.php?p=2&t=78&&n=202 BP does a pretty good job of explaining why the 'step jump' in OHC in the 2001-3 period is an artefact of the XBT-Argo transition. So not only do we not have an increase in OHC content 2004-present, we might have had little for the 17 years 1993-2010 shown on the charts. -
Alec Cowan at 22:48 PM on 14 April 2011The e-mail 'scandal' travesty in misquoting Trenberth on
@Gilles #105 At last! You're in track now. Just some clarifications: - "this means X what's exactly what I meant here" only means "I'm saying it twice", not that the conclusion is right. - You present part of the body of your argumentation again: one hand there, one leg that way ... - You continue to mix up OHC with the total ocean heat content. If you don't get it yet, you're simply echoing the set of data that seem to fit. It may sound good for uneducated people -and unfortunately the world is full of uneducated people-, but it's obvious that you are taking heat content of a layer for a period and saying "it's cooling" without bothering to explain why the same layer warmed during the previous decade at a rate above the 25 to 90 you quoted and without bothering to explain what happened with that 75% of the oceans outside that layer and ...no, not yet. Keep it going. I suppose that if you make one or two more of your comments you can get it your way: I or another person will explain you what the travesty is without you having to do an effort to understand it. -
muoncounter at 22:43 PM on 14 April 2011The e-mail 'scandal' travesty in misquoting Trenberth on
Gilles#99: "the leveling off since 2004 and perfectly visible - and continuing. " Yes, just as visible as the 'leveling off' was in 1960, 1970, 1984, 1987, 1993, 1997 and 2001. And yet the overall trend from 1970-2010 is persistently up. #102: "Of course natural noise can superimpose to long term trend and give for some time an apparent absence of warming - ... A noise can obviously go in both directions." In this case, it appears the noise is the 'leveling off.' You seem unusually sensitive to this particular noise; so much so that you cannot see the signal? -
Gilles at 22:38 PM on 14 April 2011Christy Crock #3: Internal Variability
" The point of paleoclimate studies is to help us understand past climate. The interest is largely in the forcings, not the variability as the variability is essentially paleoweather not paleoclimate." I think I see your epistemological problem - you *postulate* that the climate cannot change spontaneously over centuries without change of forcings - and you *deduce* that the changes can only be due to forcings. Do you understand that my own point is that we have neither experimental evidence, nor theoretical proof (even with computer simulations) that your first hypothesis is true ? and so that your way of reasoning is totally circular ? -
Dikran Marsupial at 22:36 PM on 14 April 2011Monckton Myth #16: Bizarro World Sea Level
Daniel Maris Yes I have read these papers, but a long time ago now. I read them when I first ran into Morner's work, it is what is called "skepticism" as opposed to "denial", which means not taking things as face value, but checking up on the facts to find out if the assertions are reasonable. You appear not to bother with that. If you think pointing out relevant papers and pointing out errors is "reverse trolling", then I have to tell you "reverse trolling" is an important part of science. Almost all papers have a sections called "references" which gives pointers to other relevant work, and where a paper argues with some existing theory or result, the errors in the previous work are pointed out in the introductory sections. Sure I could just point out some errors in the Maldives issue for you but what good would that do. I gave a detailed analysis of the false claims in the Telegraph article, but what good did that do? Have you agreed that the claims in the Telegraph artcile are false? No. Have you defended them? No. Why should I expect you to respond any differently in this case? The price of having an informed opinion on these matters is the willingness to go to the sources and sift through the facts for yourself. If you can't do that, then take on board what is said by those that do. The fact you still are unwilling to talk about the Telegraph, howevrer suggests that you are a denialist and not actually interested in the truth. Until you comment on what I have written about the Telegraph article and whether you still accept the claims made by Morner in it, I am going to assume that any further posts are just trolling. Sorry if that sounds harsh, but it is your actions that have brought it on yourself. -
Gilles at 22:31 PM on 14 April 2011The e-mail 'scandal' travesty in misquoting Trenberth on
Sorry, DB, but I don't see where I've been incorrect. I'm only answering Alec's remarks directed to me. -
Gilles at 22:21 PM on 14 April 2011The e-mail 'scandal' travesty in misquoting Trenberth on
Alec#104. Again , what are you're arguing? that energy must be conserved? of course it must ! did I deny that ? I said that when Trenberth said that they couldn't explain the lack of warming, he meant that there was a lack of warming, and that he couldn't explain it. Again, it's extremely simple : he said what he meant. Now you're saying : oh but other people have suggested that it could be due to heat storage in the deep ocean - well of course this is a *possible* explanation. But to my knowledge, there isn't precise measurements of the heat content of deep oceans. So it is only one of the possible explanation - another obvious one being that the global imbalance used is wrong. You seem to mix up suggestions with explanations. ( -Snip- )Moderator Response: [DB] Cease with making things personal. You are simply incorrect, yet incapable of admitting so. Most would regard that flaw as a failing. -
daniel maris at 22:17 PM on 14 April 2011Monckton Myth #16: Bizarro World Sea Level
Dikran, I am a little suspicious of your approach - it seems like reverse trolling. Presumably you have read these papers that you recommend I take the time to read, although I have never claimed to be trained in this area. Presumably you could sum things up pretty pithily. Presumably you could say some specific things like "That tree in Morner's photograph is no evidence because..." But you choose not to. Instead you send me off to read hundreds of pages of scientific analysis. My view of the subject is based on (1) Knowing that any effects of sea level rise in the south of the UK (which in any case is sinking) have been manageable (2) As far as I know, no one has been able to point to an island in a stable area (i.e. not an area where the land is sinking or in a delta) that has gone under water in the last 100 years. I'd be interested to hear if anyone claims there is one. (3) Dire consequences in the Maldives and elsewhere are always being predicted but never seem to happen. (4) There are clearly significant numbers of scientists who don't agree with the consensus. (5) The consensus is not the same as the extreme rises forecast by some people here - who are therefore just as guilty as denialists in ignoring scientific evidence. I've never claimed to be able to take part in a peer review of papers in this subject area. But I do think we can see given such statements as the IPCC Chair's claim about glaciers melting that there is a good degree of misinformation floating about. Bill - What do I make of the chart? Well I said I am not competent to make sense of it, but if it's real sea level as opposed to sea level in relation to land level, then I am frankly puzzled by it, since large parts of the ocean appear to be experiencing a reduction in sea level (quite substantial - 4.5 MM Pa). That makes me think there's something wrong with the measurements, or, alternatively, the measurements as a whole are not indicative of the volume of oceanic water. I presume it is the volume (or even better tonnage AND volume) of oceanic water that we are really interested in, rather than anything else.Moderator Response: [DB] Feed a man a fish and he won't be hungry - for a while. Teach a man to fish and he will never be hungry again. So take the coins of your pocket and invest them in your mind so your mind can then line your pockets with gold. Move beyond the mothers milk to real food. Dikran & Bill have given you all you need to answer your questions for yourself. -
David Horton at 22:16 PM on 14 April 2011Christy Crock #3: Internal Variability
Or, and I realise this is just one of those off-the-planet crazy ideas, we could work out the physics of CO2 in the atmosphere, and then relate the observed temperature changes (and all the associated rapid changes in this little biosphere we call home) to that, see if, by come wild chance, they happen to match. Then we could use computer modelling to work out how that might develop in future, just on the crazy off-chance that the physics and observations and knowledge of past climate shifts are correct. And then, if it looked like the planet was going to be in deep doo doo, what with acidifying oceans, increasing droughts and other severe weather events, rising oceans, melting ice caps, species extinctions, failing agriculture, why, then we could convince the world's governments that there needed to be a quick response in reducing CO2 output. Yeah, that should work I think, not as if there are going to be people trying to stop governments responding to the clear and present danger, are there? -
Gilles at 22:16 PM on 14 April 2011The e-mail 'scandal' travesty in misquoting Trenberth on
well Alec, I think I still can do simple arithmetic computation 1 W/m2 * 4 * Pi*(6,4e6)^2*365*86400 = 1,62 E22 J/yr = 162 E20 J/yr. Now the figures given here are : Land: 2 x 10^20 joules per year Arctic sea Ice: 1 x 10^20 joules per year Ice sheets: 1.4 x 10^20 joules per year Total land ice: between 2 to 3 x 10^20 joules per year Ocean: between 20 to 95 x 10^20 joules per year Sun: 16 x 10^20 joules per year (eg - the sun has been cooling from 2004 to 2008) they're all of the order of magnitude of 10^20, meaning a few % of the last result except for the ocean that can reach almost 10^22. We are speaking of one part of the 0.9W/m2 missing -meaning some 10^21 J/yr missing. This means that oceans represent the main part of heat sinks on the Earth, all the other components being negligible. That's exactly what I meant here, at the very first post of this thread : " the atmosphere stores only a tiny amount of energy" and later here " The sentence should have read: "Our measurements of how much energy goes into the atmosphere, land, and melting ice are accurately known, however."" Oh, yes, sure ! I know it accurately. On average , it's zero." Well zero is a little bit rhetorical - I should have said a few percent of the total. The heat storage takes place essentially in the oceans, all the other components are negligible. Again, what is your point ? -
Dikran Marsupial at 22:14 PM on 14 April 2011Christy Crock #3: Internal Variability
Gilles wrote "I don't think so" Well that settles it then! LOL -
Daniel Bailey at 22:13 PM on 14 April 2011Arctic Ice March 2011
Interesting, logicman, that in the rare event you make an error that you are given correction by one so petardly awash in his own unacknowledged errors. There's a saying in there somewhere about pots and kettles (and another about eyes and planks), but I won't mention it. Look forward to your update! The Yooper -
Dikran Marsupial at 22:08 PM on 14 April 2011Christy Crock #3: Internal Variability
Giles: Now you are just being silly. You can't measure climate variability from one realisation of a stochastic process if the underlying system (e.g. the forcings) is time varying. It simply can't be done without making assumptions about the nature of the noise and of the signal. This is true regardless of how much data you have, or how accurate it is. Secondly, do we have accurate measurements of past climate (beyond a century or so)? No. Are we ever going to get them? No, not unless we discover time travel. The point of paleoclimate studies is to help us understand past climate. The interest is largely in the forcings, not the variability as the variability is essentially paleoweather not paleoclimate. Of course we know that our understanding of the climate is incomplete and the model predictions may not be accurate. It would be idiotic not to realise that, and the climatologists are not idiots. Understanding climate variability does not imply an ability to predict climate variability. I understand the variability of a double pendulum, it is a very simple chaotic system, but that doesn't mean I can't predict it. The whole point of climate projections is to see what is left after excluding the effects of variability. The climate projections shown only the "forced response" of the climate. The spread of the model runs is an indication of what our understanding suggests is plausible given the unpredictable unforced response. The fact you keep harping on about the variability is merely reinforcing the impression that you don't understand how the models work, or what they tell us. Did you read the Easterling and Wehner paper? If not I suggest you do. -
Alec Cowan at 22:07 PM on 14 April 2011The e-mail 'scandal' travesty in misquoting Trenberth on
@Gilles #99 Please, set aside pompous phrases as "as a function on time" and don't distort information. The figure you placed in #99 is clearly identified as OHC700 in Levitus, Antonov, Boyer et al. Maybe if you dig a bit more and actually read the papers and figures you'd be able to find what the 'travesty' is indeed. Maybe when you reach your comment 1000 you'll realize that a) 75% of the oceans are outside what you cited, b) the travesty has to do with that, and c)your intentional double standard is more than obvious. -
Fred Staples at 22:05 PM on 14 April 20112nd law of thermodynamics contradicts greenhouse theory
I agree, Les,977,a vast improvement but a much later, and much up-dated, post than the one I quoted. Though much has gone, much remains from the original – “where does the back-radiation energy go”. It is obvious that there is no second law entropy (quality) problem if we consider only the transfers sun to earth, earth to space, and define the whole solar system as our closed system. Sadly, this ignores completely the transfers we are interested in - earth to atmosphere and back again. The most fundamental point is that you cannot consider the out and back long wave energy transfers in isolation. It is the net transfer (heat transfer) that counts. Petty, page 6, is correct and the version of Trenberth quoted here is grossly misleading. It is not just a matter of using the difference, as someone posted. We can follow G and T, and use heat engines to make the point. It is always possible in principle to convert an energy flow from a warmer source to a colder sink into work (first law). In the process the energy degrades (second law). It is never possible to do the same with an energy flow from a colder sink to a warmer source. If it were possible we would have perpetual motion. It is the net flow that counts (out minus back). The back radiation is the negative term in the Stefan Bolzmann equation. As to the “higher is colder” mechanism, 978,it has nothing to do with back-radiation. Atmospheric emission must balance incoming solar energy, and will be at an appropriate “goldilocks” temperature and elevation to make this happen. If increasing CO2 concentration elevates the emission point (for the sake of the argument) outgoing radiation will be reduced. Incoming radiation will remain the same, so the whole system warms up. The lapse rate moves to the right, and the surface warms. -
Gilles at 22:00 PM on 14 April 2011Christy Crock #3: Internal Variability
"So you got yourself an unfalsifiable hypothesis there Gilles ... useful" Of course it is falsifiable , in the way I said - we COULD find good and accurate proxies of the natural variability and of astronomical changes, TSI, volcanoes, and so on - actually this is the quest of many people in the world. The fact that we don't have them is not due to some "metaphysical" or non scientific character of the question - just to the lack of current good way of measuring it , but it is of course, in principle, measurable. -
Gilles at 21:57 PM on 14 April 2011Christy Crock #3: Internal Variability
"Easterling and Wehner is also a good answer to Gilles canard about the models ability to quantify the variability of the climate." I don't think so.Moderator Response: [DB] Cease with the trolling. -
Gilles at 21:56 PM on 14 April 2011Christy Crock #3: Internal Variability
DM : "That means you can't separate the signal from the noise without making assumptions about both the signal (the forced response) and the noise (the internal variability or unforced response)" I disagree with the assertion that only computer can answer the quesion. In principle, we could, since precise measurements of the variability, and of the natural changes of forcings in the past , could give a good estimate of it. After all, what's the use of paleoclimatic studies and past millenary reconstructions, if not ascertaining the natural variability ? but here we face another problem - the lack of accuracy of these measurements. This is not a *fundamental* problem, it is a *practical* one. If modern thermometers, satellites, and meteorological stations would have existed everywhere in the world for thousands of years, we would probably have much better estimates of the past variability. "the amount of the variability in the model is the amount of plausible variation in climate according to our best understanding of the climate. " Yes, but the "best understanding" can be bad - this has to be kept in mind. There is a number of things in the world we don't clearly understand - and I wouldn't put climate variability in the group of what we DO clearly understand. -
Dikran Marsupial at 21:50 PM on 14 April 2011Monckton Myth #16: Bizarro World Sea Level
Daniel Maris I am going to give you a hand checking up on the WUWT story regarding Morners assertions about sea level rise in the maldives. Please have a look at the following papers (which refute Morners position): John A. Church, Neil J. Whitea and John R. Hunter, "Sea-level rise at tropical Pacific and Indian Ocean islands", Global and Planetary Change, Volume 53, Issue 3, September 2006, Pages 155-168 www, pdf) Philip L. Woodworth, "Have there been large recent sea level changes in the Maldive Islands?", Global and Planetary Change, Volume 49, Issues 1-2, November 2005, Pages 1-18 (www) Colin D. Woodroffe, "Late Quaternary sea-level highstands in the central and eastern Indian Ocean: A review", Global and Planetary Change, Volume 49, Issues 1-2, November 2005, Pages 121-138 (www) but start with Paul S. Kench, Scott L. Nichol and Roger F. McLean, "Comment on 'New perspectives for the future of the Maldives' by Mörner, N.A., et al. [Global Planet. Change 40 (2004), 177–182], Global and Planetary Change, Volume 47, Issue 1, May 2005, Pages 67-69 (www) as this is a peer-reviewed comment on Morners original work on the Maldives (the details of that paper are in the title). Morner's response is here: Nils-Axel Mörner and Michael Tooley, "Reply to the comment of P.S. Kench et al. on 'New perspectives for the future of the Maldives' by N.A. Morner et al. [Global Planet. Change 40 (2004), 177–182]", Global and Planetary Change, Volume 47, Issue 1, May 2005, Pages 70-71 (www). Does the WUWT article mention any of this? If not, why do you think that is? Now I have done enough of your homework for you, it is now up to you to locate those articles (Google Scholar is your friend), read them, and then come back here and either agree that Morner is wrong about the Maldives, or give a cogent scientific defence of his claims. I predict neither of those things will occur - go on, prove me wrong! ;o) -
Alec Cowan at 21:36 PM on 14 April 2011The e-mail 'scandal' travesty in misquoting Trenberth on
@Gilles #97yes multiplying 1 W/m2 by the surface of the Earth and the number of seconds in one year gives something like 10^20 J/year - and so? what does it change ?No, it doesn't. Unless you are considering 1234 x 1020 or 0.00001234 x 1020 to be valid answers, what wouldn't surprise me. But common sense says you didn't bother -or perhaps you couldn't- make a simple calculation. Next time, in order to fool people, say "order of magnitude" instead of "something like". I meant and continue to mean it looks like you don't have any idea about what Trenberth was speaking about in the current topic -that famous email-. Your "dance with numbers" kind of confirm it. The "travesty" comes from a specific 'dialogue' conducted by mail and some contemporary works. -
Dikran Marsupial at 21:17 PM on 14 April 2011Christy Crock #3: Internal Variability
By the way, Christy says "When you look at the possibility of natural unforced variability, you see that can cause excursions that we've seen recently", then if he means the excursions we have seen over the last couple of decades, then he is right and the climate models predict that this sort of thing will happen, see the paper by Easterling and Wehner: David R. Easterling and Michael F. Wehner, "Is the climate warming or cooling?", GEOPHYSICAL RESEARCH LETTERS, VOL. 36, L08706, 3 PP., 2009 (www) This paper shows that the kinds of "excursions" we have seen over the last two decades is expected to happen due to unforced variability (although they can't predict the timing as it is a chaotic weather thing rather than a climate thing), even in the presence of a long term warming trend due to e.g. CO2 radiative forcing. Of course the longer the "excursion" the less plausible the obsertvations become assuming the model assumptions are correct (which is why the models are still falsifiable - the do make falsifiable predictions). Easterling and Wehner is also a good answer to Gilles canard about the models ability to quantify the variability of the climate. -
Dikran Marsupial at 21:06 PM on 14 April 2011Christy Crock #3: Internal Variability
Gilles wrote: "I just reminded that it was very difficult-and almost impossible - to quantify precisely the amount of internal variability by computer models " However, as I pointed out, it is the only way to estimate the internal variability of the climate - you can't measure it directly as we have only one realisation that we can observe. That means you can't separate the signal from the noise without making assumptions about both the signal (the forced response) and the noise (the internal variability or unforced response); as soon as you make a meaningful attempt to do that you end up with somthing very like a climate model. That means you can't argue that the models don't accurately quantify the amount of internal variability as you have no ground truth with which to make such a comparison. Continuing to do so just illustrates your ignorance of the subject. Giles also wrote: "you just get the amount of variability in your model, that's all.". Well duh! Of course, but as the models encode our best understanding of climate physics, the amount of the variability in the model is the amount of plausible variation in climate according to our best understanding of the climate. Given that we can't directy or indirectly measure climate variability (for the reason I have already given), how could climatologists possibly do any better than that. Note the climatologists know this perfectly well, and Gilles could do with resolving his Dunning-Kruger by reading up on climate models and what the modellers claim they can and can't do. -
Eric (skeptic) at 21:02 PM on 14 April 2011Solar Hockey Stick
Dana1981, when you say "If you want to argue that this forcing isn't driving global warming, you need both a low climate sensitivity and a larger "natural" forcing." you are speaking about the long run. Sensitivity is not a constant, it varies as a function of weather. It is likely that sensitivity was higher in the 1990's and enhanced the CO2 warming. It lowered in 2000's to amplify less. No "natural" forcings are needed to attain the variations in warming that we have seen although they are also possible inputs. CBDunkerson, the volcanic response may be short term, but having more frequent volcanoes turns into stratospheric warming over longer periods (e.g. early 20th century). Having less frequent volcanoes (late 20th century with two exceptions) means longer run stratospheric cooling. There is no equilibrium for the stratosphere since it is hit with changing factors from above (solar UV) and below (volcanoes, large scale weather patterns). We are currently in a stratospheric cooling pattern, with some very large magnitudes like NH last winter, due to GHG as a constant over the long term, plus the varying but ongoing short term factors I listed above. -
CBDunkerson at 20:57 PM on 14 April 2011Solar Hockey Stick
shawnhet wrote: "I think that there are plenty of longer term climate changes that do require some unknown mechanisms to explain them." I don't agree... and would have to wonder if you could name any of these "plenty" of long term changes... but it doesn't seem to matter. You've acknowledged (post #47) that most of the recent warming has been caused by greenhouse gas accumulation. At which point all this 'non-linear solar' and 'cosmic ray' stuff comes down to irrelevancy. Maybe they could have some kind of major effect under some kind of wacky circumstances... but they aren't right now (because the most pronounced warming spike of the past few thousand years or more is being driven mostly by GHGs) and there is no reason to think they are going to start doing so. Could some unforeseen climate forcing come along in the future and change everything? Sure. However, until there is actually some evidence of that it doesn't matter. The climate forcings we DO know about are having observed impacts which need to be addressed. -
Lars Rosenberg at 20:49 PM on 14 April 2011Monckton Myth #16: Bizarro World Sea Level
Nils-Axel Mörner's father, Stellan Mörner, was a wellknow swedish surrrealist painter, about whom he has written: "My dad's relation to his art is identical to my relation to my science." That quote may explain some of his inventiveness. -
Gilles at 20:34 PM on 14 April 2011The e-mail 'scandal' travesty in misquoting Trenberth on
100#logicman : AFAICS, the paper deals with uncertainties in the pre-2000 warming, not with the leveling off in the last decade. Of course natural noise can superimpose to long term trend and give for some time an apparent absence of warming - I guess that's what Dr Trenberth is really thinking. But it also means that the same natural noise could also have contributed positively in the past years, and that the "real" trend was after all lower than what we thought. A noise can obviously go in both directions. So in any case, that's an information that models must take into account. -
David Horton at 20:30 PM on 14 April 2011Christy Crock #3: Internal Variability
So you got yourself an unfalsifiable hypothesis there Gilles ... useful. -
Gilles at 20:28 PM on 14 April 2011Arctic Ice March 2011
suggestion , logicman : you weren't wrong because you missed something. You were wrong because your method is wrong - you didn't carefully check for the natural variability before extrapolating what you thought being a "trend" in the evolution of ice pack. Again, any "trend" must be compared with a natural historical variability before being given any significance. First express your observations as a "number of sigmas" above the average level - you may do better predictions. -
Gilles at 20:22 PM on 14 April 2011Christy Crock #3: Internal Variability
enough with strawman arguments, please. I never stated that the influence of forcings was zero. I just reminded that it was very difficult-and almost impossible - to quantify precisely the amount of internal variability by computer models - you just get the amount of variability in your model, that's all. for instance in the "solar hockey stick" post, you find this kind of curve
do you believe we have good models to explain the variation of solar activity over thousands of years ? (again I'm not speaking of the influence on the Earth, just of the origin of solar variations). No - absolutely not - not the slightest idea of where they come from. We have models of the sun - but nothing like explanations of that. So if you rely on models to know if these variations could be "natural" or "anthropogenic", would you conclude that they cannot be natural since the models do not show them, and thus must be anthropogenic ? of course this would be totally absurd. So - we can't rely on models to exclude natural cycles. And yes - natural cycles on timescales of 1000 years can exist, of course. Our modern measurements are much too recent to see them at the required accuracy.
Again I am *not* stating that the influence of CO2 is zero. Just that having a very clear separation between it and natural variations is extremely difficult in my opinion, thus reinforcing the uncertainty on the climate sensitivity - and that the outputs of computer simulations are not really useful to fix this issue.
-
bill4344 at 19:46 PM on 14 April 2011Monckton Myth #16: Bizarro World Sea Level
D'oh - make that this sort of chart! - http://en.wikipedia.org/wiki/File:NOAA_sea_level_trend_1993_2010.png -
bill4344 at 19:42 PM on 14 April 2011Monckton Myth #16: Bizarro World Sea Level
Gee, that WUWT 'photographic evidence' is, um, compelling. On the strength of those happy-snaps from the Maldives (and 4 - count them, Warmists, 4! - pics of tide gauges) the entire planet can breathe free! I wonder what Daniel Maris would make of his sort of chart?
(Speaking of Watts; should we await the Tidal Stations Project with bated breath?)
Moderator Response: [DB] Fixed & hyperlinked chart link. -
Arkadiusz Semczyszak at 19:40 PM on 14 April 2011Christy Crock #2: Jumping to Conclusions?
@Tom Curtis „... dominating influence of the sun ...” I do not say here, the dominant role of the Sun. I (as Christy) say that it is poorly understood and works through delays and too poorly understood feedbacks - it may be estimated wrong: being too big - as you want - but also too small ... The papers, I have cited, say that there is no simple and sufficiently well-known relations - TSI - changes in global temperature. Remember that revealed many solar cycles - can be their superposition. Remember for example the recent (2009) found the cycle c. 6 thousand. years and Holocene optimum. A propos Holocene Optimum - here there were several new papers - worth this topic returning to Sk.S. Steinhilber and Beer, 2011 said several times (outside think cited by MichaelM) that are supporters of the theory of the dominant - currently - the role of A. GHG. But it is precisely because of their sentence, cited by me - has special value. I can cite a similar view of another "hot" supporter of the theory of AGW - Lockwood's,: „... the current grand maximum has already lasted for an unusually long time ...” ... but - the references to these two papers, is not cited by me papers .. -
Bart Verheggen at 19:19 PM on 14 April 2011Christy Crock #3: Internal Variability
A lighthearted take on this issue: Harry Potter lost at sea. If a boat has both an engine running and a sail, it makes no sense to claim that the engine has no effect on the boat's movement. -
Dikran Marsupial at 19:13 PM on 14 April 2011Christy Crock #3: Internal Variability
Gilles Given that the only way to estimate the amount of internal variability is from a climate model (as we have only one realisation of the signal that we have actually observed), it is impossible to say whether the models estimate it "accurately". The error bars on the model projections (which show how much variability is possible) include the observations, which is all that can be expected of the models even if the physics of the model is exactly correct. The climate modellers know this already. Why do you keep on about the models proving anything? They don't and nobody is claiming they do. Models show you the (testable) consequences of a set of assumptions about climate physics. They tell us what we can expect to see based on our best understanding of the climate. Nothing more. As for random initialisations, initialising the initial conditions with the observations for a randomly chosen day would be a random initialisation, and would be a physically realistic initialisation, by definition. As I said, it would be better for you to stop posting on this topic until you have done some background work, you are still just demonstrating your ignorance. -
Gilles at 19:03 PM on 14 April 2011Christy Crock #3: Internal Variability
DM : sorry for repeating : I wasn't wrong, I wasn't speaking of the climate of the Earth but of stellar physics". Replace the sun by a variable star without planets , if you prefer ! I just gave this example of another natural limit cycle which is not due to a variation of forcing. "The whole point of the ensemble is to find out what the climate is doing after internal variability is excluded. " My point is : they're not reliable to estimate the precise amount of internal variability. So they adjust their results to match observations without being certain that the relative proportion of internal variability and sensitivity to forcings is the right one. And the fact that the simulations do not show a long term trend doesn't prove anything. " A large number of model runs are used, all with different random initialisations." There is nothing like "random numbers" in an unrestricted interval. There *must* be a range in which you draw your parameters. Again : how is this range chosen following you ?Moderator Response: [Dikran Marsupial] tags fixed (hopefully the way you wanted them) -
Riccardo at 18:45 PM on 14 April 2011Monckton Myth #16: Bizarro World Sea Level
How can even ultra-skeptics still oppose "photographic evidence" to real science after the debacle of the surfacestation project? -
Dikran Marsupial at 18:40 PM on 14 April 2011Christy Crock #3: Internal Variability
Giles It would be better if you could just admit when you were wrong. The 11 year solar cycle is an external forcing to the models, not part of the models (it has very little effect on the climate anyway). I note you dodge the more substantive issue though, the model projections do not depend on any of the model runs predicting the effects of internal variability accurately. Like other Monte Carlo methods, they don't even attempt to predict internal variability. The whole point of the ensemble is to find out what the climate is doing after internal variability is excluded. If you understood climate modelling, you would know that. Again you last comment demonstrates you don't understand what climate models do. Weather is chaotic, it can't be predicted because we don't have accurate initial conditions (one of the founding fathers of chaos theory, Edward Lorenz, was a meteorologist, chaos theory has its origins in weather modelling, so of course climate modellers are perfectly aware of this). However, just because weather is chaotic, that doesn't mean climate (long term statistical behaviour of the weather) is also chaotic. So rather than predict the chaotic weather, the models simulate weather with the same statistical properties as the real weather and take averages to get information about climate. A large number of model runs are used, all with different random initialisations. After a while, the behaviour of the model is statistically independent of the intialisation (In Monte Carlo simulation, this is called "burn in"). You need initial conditions for weather prediction, which is why weather forecasts are useless beyond five days or so; you don't need them for climate modelling. The reason for choosing 1880 has to do with the availability of reasonably reliable instrumental data (hint, when does GISTEMP start?). I would have thought that was obvious. What is the point of generating hindcasts if you don't have something to use as ground truth? BTW climate models are often used for paleoclimate studies, so it isn't even true that they necessarily start at 1880. I suggest that rather than demonstrate your ignorance of climate modelling and Monte Carlo methods any further, you do some reading and fill in the gaps in your knowledge.Moderator Response: [Dikran Marsupial] This discussion of modelling is heading a bit off-topic. I suggest if you want to discuss what models can and can't do, we continue on climate models are unreliable, although I suggest you read the article and the posts on that thread first. You may also find this post informative, where I use a simpler chaotic system to explain the basic aim of climate modelling and how it works (and why initial conditions are not important).
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