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Daily Mangle

Filed under: — group @ 15 February 2010

Yesterday, the Daily Mail of the UK published a predictably inaccurate article entitled “Climategate U-turn as scientist at centre of row admits: There has been no global warming since 1995″.

The title itself is a distortion of what Jones actually said in an interview with the BBC. What Jones actually said is that, while the globe has nominally warmed since 1995, it is difficult to establish the statistical significance of that warming given the short nature of the time interval (1995-present) involved. The warming trend consequently doesn’t quite achieve statistical significance. But it is extremely difficult to establish a statistically significant trend over a time interval as short as 15 years–a point we have made countless times at RealClimate. It is also worth noting that the CRU record indicates slightly less warming than other global temperature estimates such as the GISS record.

The article also incorrectly equates instrumental surface temperature data that Jones and CRU have assembled to estimate the modern surface temperature trends with paleoclimate data used to estimate temperatures in past centuries, falsely asserting that the former “has been used to produce the ‘hockey stick graph’”.

Finally, the article intentionally distorts comments that Jones made about the so-called “Medieval Warm Period”. Jones stated in his BBC interview that “There is much debate over whether the Medieval Warm Period was global in extent or not. The MWP is most clearly expressed in parts of North America, the North Atlantic and Europe and parts of Asia” and that “For it to be global in extent, the MWP would need to be seen clearly in more records from the tropical regions and the Southern hemisphere. There are very few palaeoclimatic records for these latter two regions.”

These are statements with which we entirely agree, and they are moreover fully consistent with the conclusions of the most recent IPCC report, and the numerous peer-reviewed publications on this issue since. Those conclusions are that recent Northern Hemisphere warming is likely unprecedented in at least a millennium (at least 1300 years, in fact), and that evidence in the Southern Hemisphere is currently too sparse for confident conclusions. Mann et al in fact drew those same conclusions in their most recent work on this problem (PNAS, 2008).

Unfortunately, these kinds of distortions are all too common in the press nowadays and so we must all be prepared to respond to those journalists and editors who confuse the public with such inaccuracies.

Update 2/16/10. Phil Jones has confirmed to us that our interpretations of his comments in the BBC interview are indeed the correct ones, and that he agrees with the statements in our piece above. He and his CRU colleagues have also put up an response to some of the false allegations in a previous piece in the UK Guardian. We’ll report further such developments as they happen.


493 Responses to “Daily Mangle”

  1. 401
    Completely Fed Up says:

    “It is blindingly obvious that a 15-year trend (or less) on such noisy, and arguably naturally cyclic data as in HADCRUT, cannot be used for longer term prediction”

    Incorrect.

    It’s far too short a period of time to draw a conclusion about the past that can be relied upon to remain in the future.

    Different.

    “1) The 30-year 21 point smoothed trend from 1910 to 1940 is remarkably similar to the rapid warming from ~1970 to ~2000*”

    How is this proving anything wrong?

    “2) The 30-year 21 point smoothed trend from 1940 to 1970 shows moderate cooling”

    http://en.wikipedia.org/wiki/Clean_Air_Act

    Dog bites man.

    “3) The 30-year 21 point smoothed trend from 1925 to 1955 is flat.”

    So we have two warming, one cooling and one flat.

    +,+,-,0.

    I would call that overall “+”.

    You’re doing well at proving global warming.

    “Thus, in that time-series from 1910 to 1970, no individual 30-year period has any meaningful implications”

    Yes it has. The early warming has shown that it’s generally warmed since too.

    Or didn’t you read the graph:

    http://data.giss.nasa.gov/gistemp/graphs/Fig.A2.lrg.gif

    ‘cos it looks like those warming periods were indicative of a warming period overall too.

    “As described in my 380, two acclaimed scientists; Tom Wigley and Kevin Trenberth have agreed, with wide compliant circulation, that the current warming plateau is of unknown cause.”

    This is false. In two ways:

    1) there’s no plateau. The period is too short. There have been record breaking years since the plateau was “discovered”, therefore it wasn’t discovered. If you keep finding a new peak, you were never at the peak before.

    2) They maintain that they can’t be CERTAIN why but that they know where the heat is going: into the deep oceans. This is why Tenenberth decries the poor sensor station for the deep ocean.

    If they didn’t know where the heat was going, they wouldn’t know how to prove it, would they.

  2. 402
    Ken Lambert says:

    Completely Fed Up #401

    Dr Trenberth’s Aug09 paper mentioned in the famous emails has a starting point. He starts with a warming imbalance of 0.9W/sq.m which equates to 145E20 Joules/year applied to the whole planet’s surface.

    The O.9W/sq.m is made up from radiative forcing elements quoted in IPCC AR4 Fig 2.4 plus various feedbacks. Dr Trenberth makes the point that this number is not derived from direct measurement because the devices for such are not accurate enough. ie. an imbalance of 0.9 W/sq.m is not possible to directly measure in the roughly 240 W/sq.m of energy flux passing through the atmosphere. So the 0.9 number is composed from climate model corrections and indirect measurements, feedbacks etc (difficult to describe all the components).

    Dr Trenberth then goes on to account for a range of 45-115 E20 Joules/year (av 80) by best estimates of ice melt, land warming and ocean warming etc leaving a residual of 30-100 E20 Joules/year (av 65).

    So of the 145 he accounts for roughly 80 and a residual of 65. That is the current state of play. The 80 accounted for represents an imbalance of about 0.55W/sq.m of his assumed starting point of 0.9W/sq.m.

    In the Aug09 paper and a particular email he suggests that brightening of clouds could be an unmeasured factor. Cloud albedo has a low LOSU and wide error bars in the IPCC AR4 Fig2.4 forcing numbers requoted in Dr Trenberth’s paper.

    The Clean Air Act reductions in SO2 are quoted as explaining the cooling of 1940-70 but there were few if any direct measurements, and the Clean Air Act does not apply to current India & China (the world’s most reliable witnesses to these emissions).

    I would suggest that the places to look hard at the discrepancy between the proposed 0.9 W/sq.m warming imbalance and the roughly accounted 0.55 W/sq.m are:

    1) Cloud Albedo increase from unaccounted emissions,
    2) Much more accurate measurement of ocean heat content.

  3. 403
    BobFJ says:

    Completely Fed Up 401:

    [1] Incorrect. It’s far too short a period of time to draw a conclusion about the past that can be relied upon to remain in the future.

    Uh? Let me repeat what I wrote in part: “It is blindingly obvious that a 15-year trend (or less) on such noisy, and arguably naturally cyclic data as in HADCRUT, cannot be used for longer term prediction.”
    Where was it that you were confused?

    [2] Different. “1) The 30-year 21 point smoothed trend from 1910 to 1940 is remarkably similar to the rapid warming from ~1970 to ~2000*” How is this proving anything wrong?

    I did not say that it proves anything wrong, and neither do I think so. What is your point?

    [3] “2) The 30-year 21 point smoothed trend from 1940 to 1970 shows moderate cooling”
    http://en.wikipedia.org/wiki/Clean_Air_Act Dog bites man.

    Actually, I don’t trust Wikipedia on AGW issues that were likely given a “personal touch” by William Connelly. My reading is that the sulphur aerosol argument has been discredited, partly because of regionality comparisons, and, for instance, you may find that Wild (ICAS Zurich) et al (NOAA & Russian Geophysical Observatory) 2005, to be interesting. Apart from that, you need to look more carefully at the HADCRUT graph, and explain why the cooling trend between ~1880 through 1910 was greater than that between ~1940 through 1970, which in the latter case you apparently assert to have been caused by increasing pollution, together with increasing CO2, after WW2.

    [4] “3) The 30-year 21 point smoothed trend from 1925 to 1955 is flat.” So we have two warming, one cooling and one flat. +,+,-,0. I would call that overall “+”. You’re doing well at proving global warming.

    Uh? We have one strong warming period, one moderate cooling period, and one flat period.

    [5] “Thus, in that time-series from 1910 to 1970, no individual 30-year period has any meaningful implications” Yes it has. The early warming has shown that it’s generally warmed since too.
    Or didn’t you read the graph: http://data.giss.nasa.gov/gistemp/graphs/Fig.A2.lrg.gif
    ‘cos it looks like those warming periods were indicative of a warming period overall too.

    If you are going to quote me, please be so kind as to not show just half of a sentence with consequent loss of context. I referred you to HADCRUT because that is what the IPCC prefers to use.

    [6] “As described in my [Bob_FJ] 380, two acclaimed scientists; Tom Wigley and Kevin Trenberth have agreed, with wide compliant circulation, that the current warming plateau is of unknown cause.”
    This is false. In two ways:
    1) there’s no plateau. The period is too short. There have been record breaking years since the plateau was “discovered”, therefore it wasn’t discovered. If you keep finding a new peak, you were never at the peak before.
    2) They maintain that they can’t be CERTAIN why but that they know where the heat is going: into the deep oceans. This is why Tenenberth decries the poor sensor station for the deep ocean.
    If they didn’t know where the heat was going, they wouldn’t know how to prove it, would they.

    Uh? Reur 1): Not to mention other sources, check-out Barton Paul Levenson’s 398/p7, where he wrote:
    It [the plateau] exists, but it has no meaningful implications because it’s too short to accurately determine the trend. (to which I have agreed, WRT the longer term)
    Uh? Reur 2): How about you read my 380 & 388 and their responses more carefully? For instance, briefly; Trenberth has said this: “…We are not close to balancing the energy budget. The fact that we can not account for what is happening in the climate system makes any consideration of geoengineering quite hopeless as we will never be able to tell if it is successful or not! It is a travesty!…” (But there is more if you are not yet convinced!)

  4. 404
    Completely Fed Up says:

    “The Clean Air Act reductions in SO2 are quoted as explaining the cooling of 1940-70 but there were few if any direct measurements”

    And anything not measured doesn’t exist, right?

    So, since the vikings didn’t measure the temperature of greenland, it wasn’t warm, yes?

  5. 405
    Completely Fed Up says:

    “Uh? Let me repeat what I wrote in part: “It is …”"

    a) In part.

    b) Your statement doesn’t lead to your conclusion without more explicit steps. Do so.

    “I did not say that it proves anything wrong, and neither do I think so. What is your point?”

    The point is that your conclusion doesn’t follow from your precis.

    Was there some ambiguity in that?

    “Actually, I don’t trust Wikipedia on AGW issues ”

    But you WILL trust WUWT and CA?

    You also won’t trust the IPCC, Nature, NAS, The Royal Society, or Realclimate.

    There does seem to be a trend of what you WILL trust.

    You will trust any source that says AGW is wrong.

    Do I need to point out your display of bias any more clearly?

    “If you are going to quote me, please be so kind as to not show just half of a sentence with consequent loss of context.”

    Isn’t it ironic that this complaint turns up in a thread about the Daily Mail showing half a sentence with consequent loss of context, yet not once has Bob bobbed up and agreed that should not have been done

    “Reur 1): Not to mention other sources, check-out Barton Paul Levenson’s 398/p7, where he wrote:
    It [the plateau] exists, ”

    IF

    Funny how you quoted it and ignored it. Quoting something doesn’t mean you haven’t riven all context and mischaracterised anothers’ statement. You have to characterise a person’s statement correctly.

    Fail.

    “Uh? Reur 2): How about you read my 380 & 388 and their responses more carefully? For instance, briefly; Trenberth has said this: “…We are not close to balancing the energy budget.”

    We are not close to balancing the energy budget doesn’t mean what you want it to mean.

    They haven’t MEASURED it. See my post above re: measuring doesn’t make something exist.

    And again, that quote doesn’t deny my point #2.

    Double fail.

  6. 406
    Ken Lambert says:

    Completely Fed Up (CFU)#404 and KL #402

    Why don’t you give us your data on Aerosols back to 1940 CFU? My point in #402 was that even IPCC AR4 Fig 2.4 shows aerosol cooling forcing with the widest error bars – indicating greatest uncertainty of measurement.

    The Viking analogy would be; “Yes it was warmer in Greenland in the MWP – but how much?”

    ‘How much’ is vital to this whole AGW debate. If we have half the warming forcing then we have half the problem.

  7. 407
    Chris says:

    I am quite curious about the Jones comment on no statistical warming since 1995. Every time I download the latest HadCRUT or HadCRUT3v data set (Global,monthly) and plot it I get a statistically significant linear least squares regression for the (admittedly) short interval 1995-2009.

    What data set is Jones referring to that fails to show a statistically significant warming since 1995?

  8. 408
    Completely Fed Up says:

    Chris, please show your workings, intermediate calculations and your method of ascertaining statistical significance.

  9. 409
    Completely Fed Up says:

    “406
    Ken Lambert says:
    28 February 2010 at 8:36 AM

    Completely Fed Up (CFU)#404 and KL #402

    Why don’t you give us your data on Aerosols back to 1940 CFU? ”

    What makes you think I have data on Aerosols back to 1940? What makes you think I have to give you any if I do have some?

    I won’t do your homework. The datasets are available. Get them yourself.

  10. 410
    Dave G says:

    Ken Lambert says:
    28 February 2010 at 8:36 AM

    “The Viking analogy would be; “Yes it was warmer in Greenland in the MWP – but how much?””

    How can you have a RC thread without Greenland being mentioned? Tradition is a wonderful thing, though I am getting a bit fed up with this one.

    Greenland’s surface is about 80% ice now. It was about 80% ice when the Norse (not Vikings) settled there about 1,000 years ago. If it was warmer during the MWP, it wasn’t by much.

    It must be time for you to mention something about English vineyards now.

  11. 411
    Hank Roberts says:

    Ken Lambert says: 25 February 2010 at 8:08 PM (incorrectly) that there weren’t measurements of sulfates. Sulfate control was one of the early cap-and-trade successes. Ken, what’s your source for this misinformation, why did you believe it, and can you do better?

    Google Scholar finds them easily.

  12. 412
    Jedda says:

    Barton Paul Levenson
    I’ve had a look at your website and see that you are very active in the field of climate change and also computer programming. (Does that include climate modelling?)

    I found the following post (No.399) that was addressed to you to be very interesting, but it was only answered by Completely Fed Up, and I thought he/she was unhelpful. (And contradicted some things you wrote earlier)
    http://www.realclimate.org/index.php/archives/2010/02/daily-mangle/comment-page-8/#comment-162849

    You seem to be better qualified to make a more helpful response.
    Could you please? I’m very interested

  13. 413
    BobFJ says:

    Hank Roberts Reur 411

    “…Sulfate control was one of the early cap-and-trade successes. Ken, what’s your source for this misinformation, why did you believe it, and can you do better?…“

    Pardon me Ken for intruding on your exchange with Hank, but there has not been a response to a relevant point I raised earlier with others in my 403, item [3]

    “…Apart from that, you need to look more carefully at the HADCRUT graph, and explain why the cooling trend between ~1880 through 1910 was greater than that between ~1940 through 1970, which in the latter case you apparently assert to have been [otherwise] caused by increasing pollution…”
    http://www.cru.uea.ac.uk/cru/data/temperature/_nhshgl.gif.

    Please clarify Hank….! What reduced the sulphates prior to 1940?

  14. 414
    Completely Fed Up says:

    “Please clarify Hank….! What reduced the sulphates prior to 1940?”

    Please prove that the pre-1940 episodes were produced by sulphate aerosol reduction.

    There’s more than just one factor. Read up on the source code for a model to find out how many factors are included in a GCM:

    http://www.giss.nasa.gov/tools/modelE/

  15. 415
  16. 416
    Ray Ladbury says:

    BobFJ,
    Sulfates were lower in the 1910-1940 period due to abnormally low volcanic activity:

    http://tamino.wordpress.com/2008/10/19/volcanic-lull/

  17. 417
    Ken Lambert says:

    Comment #413 by Hank Roberts — 28 February 2010

    Hank, direct measurement of the cloud albedo effects of aerosols has only been available since 1980. The IPCC AR4 Fig 2.4 and extensive data in WG1 still show total aerosol cooling ranges of -0.3 to -1.8 W/sq.m (cloud albedo) and -0.1 to -0.9 W/sq.m (direct effect). The averages of these cooling effects are included in Dr Trenberth’s +0.9 W/sq.m proposed warming imbalance. The LOSU (level of scientific understanding) of these Aerosol cooling effects are rated by the IPCC AR4 as Low and Med-Low.

    So Hank and CFU, is it reasonable to look for Dr Trenberth’s 0.45 W/sq.m missing heat in Radiative Forcing Components which have the largest combined cooling forcing (-1.2 W/sq.m) and the widest error bars roughly (+/-1.15 W/sq.m) and the lowest level of scientific understanding??

  18. 418
    Chris says:

    @FedUp:
    I have since found out that I was failing to take into account autocorrelation of the time series data, and since I am not that stats savvy I’m still trying to work through it.

    But here’s what I did:
    I downloaded the GL data set from Hadley (HadCRUT3v) then I merely fit a least squares regression to the monthly temp anomaly vs date for the short time frame of 1995 to 2009 and ran a t-test on the fit which came out significant at 95% confidence.

    But since the data is really pretty autocorrelated I was likely underestimating the possibilty of Type I error.

    So right now I’m trying to teach myself more time-series stats and figure out how to pull out a slope with appropriate t-test.

  19. 419
    Hank Roberts says:

    > Ken Lambert says: 1 March 2010 at 8:10 AM ….
    Trust me on this — asking questions specifically of other ordinary readers here to tell you what’s reasonable isn’t likely to get you much information. Try looking it up or asking one of the climate scientists if you actually want to learn something. If you want my opinion — that’s it.

  20. 420
  21. 421
    Completely Fed Up says:

    “418
    Chris says:
    1 March 2010 at 10:24 AM

    @FedUp:
    I have since found out that I was failing to take into account autocorrelation of the time series data, and since I am not that stats savvy I’m still trying to work through it. ”

    Aye, I’ve nothing beyond “RMS errors == error in graph slope” either.

    That’s why, though, I asked (OK, it looks more like a demand) for the workings. It’s also why you don’t need his workings: just his method.

    It was his method, not his data you were lacking.

    Compare and Contrast with McIntyre’s insistence on data and ignorance on method.

  22. 422
    Completely Fed Up says:

    Ken : “So Hank and CFU, is it reasonable to look for Dr Trenberth’s 0.45 W/sq.m missing heat in Radiative Forcing Components ”

    It’s more reasonable to look for it going down into the ocean. Or coming out.

    If you’ve looked for your keys in your coats, in the drawers and on the tabletops, but you know you haven’t looked behind the sofa, you don’t decide to look in the hedges for your keys…

    PS isn’t that forcing the maximum delta? It’s a bit alarmist to call it on the maximum and leave “how long” out.

  23. 423
    John E. Pearson says:

    418: Chris says: “I downloaded the GL data set from Hadley ”

    You can do that but you also ought to download the other data sets and you also ought to understand how the Hadley mean is computed. Gavin has written on this. GISS takes the land-based stations around the Arctic Ocean and interpolates between them which, in essence, gives estimates of the Arctic temperatures. Hadley computes averages and leaves the Arctic out of it. As Gavin has written, what Hadley does is equivalent to assuming that the change in the Arctic mean is identical to the rest of the planet.

    http://www.giss.nasa.gov/research/news/20100121b/

  24. 424
    Ken Lambert says:

    Comment #419 by Hank Roberts — 1 March 2010 @ 11:10 AM

    “Try looking it up or asking one of the climate scientists if you actually want to learn something. If you want my opinion — that’s it.”

    Quite right Hank. Why don’t we ask Gavin to chime-in on this point.

    Over to you Gavin.

    CFU #422 – “It’s more reasonable to look for it going down into the ocean. Or coming out.”

    Read #389 again CFU:

    “A recent paper by Von Schukmann et al suggests that 0.77 W/sq.m of ocean area equivalent forcing of heat over recent times is stored down to 2000m using Argo data. There is no clear description of mechanism or how it passes through the top 700m without showing up in other Argo analyses.”

    AND

    Read #403 again CFU:

    I would suggest that the places to look hard at the discrepancy between the proposed 0.9 W/sq.m warming imbalance and the roughly accounted 0.55 W/sq.m are:

    1) Cloud Albedo increase from unaccounted emissions,
    2) Much more accurate measurement of ocean heat content

    Yes??

  25. 425
    Hank Roberts says:

    > Ken Lambert
    > missing heat
    Are you familiar with the Wattsup discussion raising this question already?
    http://www.google.com/search?q=Dr+Trenberth%E2%80%99s+0.45+W%2Fsq.m+missing+heat
    I wasn’t able to find any science papers about “missing heat” and it looks more like someone’s trying to make a fixed number out of an uncertainty range.
    Do you know of any publication on the subject?

  26. 426
    Hank Roberts says:

    I found one paper by Trenberth using Scholar mentioning that number:

    “About 0.45°C of the SST anomaly is common to global SST and is thus linked to global warming …”. Citation: Trenberth, K. E., and D. J. Shea (2006), Atlantic hurricanes and natural variability in 2005, Geophys. Res. Lett., 33, L12704, doi:10.1029/2006GL026894

  27. 427
  28. 428
    BobFJ says:

    Ray Ladbury, Reur 416:

    Sulfates were lower in the 1910-1940 period due to abnormally low volcanic activity:

    Thankyou for the link to a Tamino article on this wherein he describes a 30-year lag in the cooling effect of volcanic eruptions. However, I some difficulties with that assertion. A good example for consideration of it is the Mauna Loa record of reduced solar transmission through the atmosphere attributed to the famous El Chichon and Pinatubo events @:
    http://upload.wikimedia.org/wikipedia/commons/9/9c/Mauna_Loa_atmospheric_transmission.png (See footnote $)
    From this you can see that the dimming is a sharp spike initially but then tails off exponentially over maybe 4-years.
    Now let us consider an analogy with a pot of hot water on a stove at an equilibrium temperature of say 90C and a thermostat setting of say 7. Now let us turn down the thermostat to say 6 for a short period. There would be a consequent cooling of the water and the pot that would be quite pronounced initially, trailing off exponentially. Now let us return the thermostat to the original 7 heat input setting. The pot and the water would return to their original equilibria after a period. However, Tamino asserts that AFTER any such cooling effect, such as the analogous thermostat reverting back from 6 to 7, the system will continue to cool despite increased heat input. As a retired engineer familiar with thermodynamics, I’m somewhat puzzled by this assertion. Any chance that you could clarify it please Ray?

    $ Note: if you have older Quicktime software, it may be anoyingly slow to open or remain inactive as a tab above unless you click.

  29. 429
    Completely Fed Up says:

    “I would suggest that the places to look hard at the discrepancy between the proposed 0.9 W/sq.m warming imbalance and the roughly accounted 0.55 W/sq.m are:”

    As Hank said: error bars.

    When I measure the length of a piece of rope to 12.3m+/-0.09m that doesn’t mean there’s 9cm of rope missing.

  30. 430
    Martin Smith says:

    I have been following this anomaly map all winter, ever since someone posted the link to RC.

    http://www.esrl.noaa.gov/psd/map/images/rnl/sfctmpmer_07a.rnl.html

    Now the main cold anomaly seems to be shifting back up north, but the map has shown all winter that eastern Canada and Greenland have been much warmer than the mean, and pretty much the entire Arctic Circle has been warmer than its mean all winter. Yet I haven’t seen this map used anywhere to shoot down the “It’s snowing in the eastern US so climate warming is false” argument. Why not? Am I misreading the anomaly map?

  31. 431
    Ken Lambert says:

    CFU #429

    And what do you say about a rope which is 12.3m+/- 12.0m CFU? What are the chances of it being about 3.6m shorter or longer??

  32. 432
    Completely Fed Up says:

    “431
    Ken Lambert says:
    2 March 2010 at 8:26 AM

    CFU #429

    And what do you say about a rope which is 12.3m+/- 12.0m CFU?”

    Noting.

    what I say is “I think I need a better way to measure rope”.

    I still don’t say that there’s 12m of rope missing.

  33. 433
  34. 434
    john byatt says:

    John cook, http://www.skepticalscience.com/ has just posted what must be the longest list of sceptical arguments {242}on one site. with links.
    John has been a tireless worker in getting the science of AGW out there, time for some support?

  35. 435
    Ken Lambert says:

    CFU #432

    I did not say that 12m of rope was missing either CFU. I said: “What are the chances of it being about 3.6m shorter or longer??”

    These are the proportions we are talking about with finding 0.35 in -1.2 +/-1.15

  36. 436
    BobFJ says:

    Ray Ladbury, in your 416, you cited an article by Tamino:
    http://tamino.wordpress.com/2008/10/19/volcanic-lull/
    I commented in my 428 that the thermodynamics hypothesis made by Tamino was false, and I’m surprised that you have not responded, or, for that matter, neither has Hank or CFU, that have freely commented on other aspects of that issue.
    There is an additional problem with the Tamino article. Is anyone interested in an elaboration, given that you have cited the article?

  37. 437
    David B. Benson says:

    BobFJ (436) — The characteristic response time for ModelE is, I take it, about 30 years. A volcano erruption is approximately an impulse function and so the linear system response is of the form exp(-t/30) for t the time in years. That’s irrespective of the sign of the impulse.

    If there is an actual problem with
    http://tamino.wordpress.com/2008/10/19/volcanic-lull/
    of course we want to know, but please do not waste time and keying as you have so far.

  38. 438
    Ray Ladbury says:

    BobFJ, Tamino is not positing a 30 year lag. Rather he is saying that the atmosphere responds quickly, but that the oceans respond to the perturbation with a much longer time constant. There’s nothing controversial about this.

    Tamino has used the 2-layer model to good effect on several occasions. I would recommend that you read the piece more closely. It’s quite instructive, as is this one.

    http://tamino.wordpress.com/2009/08/17/not-computer-models/

  39. 439
    t_p_hamilton says:

    BobFJ needs to wake up and smell the coffee:”Now let us consider an analogy with a pot of hot water on a stove at an equilibrium temperature of say 90C and a thermostat setting of say 7. Now let us turn down the thermostat to say 6 for a short period. There would be a consequent cooling of the water and the pot that would be quite pronounced initially, trailing off exponentially. Now let us return the thermostat to the original 7 heat input setting. The pot and the water would return to their original equilibria after a period. However, Tamino asserts that AFTER any such cooling effect, such as the analogous thermostat reverting back from 6 to 7, the system will continue to cool despite increased heat input.”

    Your situation is the reverse, let us map it to the example as closely as possible (your idea, not taminos). Using the volcanic forcing graph on his volcanic lull post:

    1) The pot and coffee are in equilibrium in 1880.
    2) The burner gets cranked down dramatically in 1883, rapid cooling at surface. Heat starts to slowly leave the bulk coffee away from the surface.
    3) The burner is turned back up, heating at surface resumes. Heat starts to slowly enter the bulk coffee from the surface.
    4) The burner is turned back down.
    5) repeat ad nauseum, there is a fluctuation, but some characteristic average temperature in the bulk coffee.
    6) after one of the returns of the burner to up (1910) – stop fiddling with the knob, leave the burner on.
    7) There is an eventual new equilibrium, higher than the original undulating one
    8) this is the heating that tamino is describing by smoothing the effect of fast knob twiddling on a system with a fast component and a slow component response time.

    now to your critique – turn the burner down, arguing that continuing to heat is fallacious. The temperature would go down in tamino’s model, if not for the IR heater that has been cranked up in the 20th century. Not immediately, because it is not a physical model. You’re missing the point.

    However, a physical model shows the same thing that tamino concuded: http://www.iac.ethz.ch/people/knuttir/papers/knutti08jgr.pdf

  40. 440
    Hank Roberts says:

    BobFJ, why ask _me_? Tamino’s over there, and the topic’s available.

    I suspect you’re confusing air temperature change with ocean lag time, but you should address the math, not just claim your stovetop analogy falsifies it.

  41. 441
    Completely Fed Up says:

    “commented in my 428 that the thermodynamics hypothesis made by Tamino was false, and I’m surprised that you have not responded, or, for that matter, neither has Hank or CFU, that have freely commented on other aspects of that issue.”

    OK, I’ll respond: Please show your proofs.

  42. 442
    Completely Fed Up says:

    “435
    Ken Lambert says:
    2 March 2010 at 9:08 PM

    CFU #432

    I did not say that 12m of rope was missing either CFU.”

    You are in the system to which we are analogising to a rope measuring experiment: the 0.45W you blather on about.

  43. 443
    BobFJ says:

    Hank Roberts Reur 440:

    BobFJ, why ask _me_? Tamino’s over there, and the topic’s available.

    Well, I did ask him on March 4, 2010 at 4:03 am, his blog time, but my post was deleted without comment.

  44. 444
    BobFJ says:

    Ray Ladbury Reur 438:
    Thanks your citation of yet another article by Tamino!
    However, the very first word he uses is ‘denialist‘, and skipping through it, ‘denier’ is liberally sprinkled throughout.
    Thus, since I am not in that category, but merely sceptical of some claims in the AGW debate, I don’t find it to be suitable reading.

  45. 445
    Sekerob says:

    444 BobFJ, I’ve long switched to the “Ain’t True-ist” reference. Would that make it better reading? If you’re skeptical of some “claims” as you put it, there’s loads of research, peer reviewed and all that can confirm or reject, or at least when taken together build an outline view of where the truth is. If you’ve gone out to find that, then you’re a skeptic, but a skeptic has no issue judging the evidence on it’s merits. “Ain’t True-ists” don’t and can’t. They summarily dismiss, because they’re told so, by whatever, whoever [and often paid for]… many in the BAU department, who can’t care about what comes after them, no I don’t think a superior being will fix it for us. We’re on our own in that.

  46. 446
    BobFJ says:

    Re: 437*, 438, 439, 440, 441 & 442:
    Thanks all of you for your varied responses.
    But….. repeating part of my 428:

    “…[see for example] the Mauna Loa record of reduced solar transmission through the atmosphere attributed to the famous El Chichon and Pinatubo events @:
    http://upload.wikimedia.org/wikipedia/commons/9/9c/Mauna_Loa_atmospheric_transmission.png
    From this you can see that the [volcanic] dimming is a sharp spike initially but then tails off exponentially over maybe 4-years…”

    If you examine this closely, you should see that most of the time the insolation transmission is about 93%, but then there are the two big down-blips which I eye-ball to be at about 88-89% average over only about 4 years each.
    The fundamental slow response heating mechanism of the oceans is via insolation, (EMR), but with minor secondary effects of rapid response from (conductive/advective) air temperature and radiative GHG effects. However, the heat loss from the oceans overall is arguably roughly equal to the heat gain, but it is rather more complicated in detail;
    For a start, roughly 40% of the insolation is in the near IR, which is mostly absorbed in the surface “skin“, where it is rapidly able to re-emit as long-wave EMR. The other ~60% is absorbed progressively at much greater depths down to a maximum towards blue. (by some six orders of magnitude I think from memory?). Thus, if there is any heat loss from the greater depths, that must fundamentally rely on conduction and convection/advection, which will be at its maximum when there is lower SST and/or Air T, and less EMR from above. It is further complicated by evaporative cooling, and by oceanic circulation, but whatever, most of the heat input remains most of the time at a roughly constant level in a slow response regime. (as does evaporative cooling, and slow response ocean heat content)

    The fundamental consideration, per thermodynamics law 2, is that heat transfer between any point 1 and point 2 is in the fundamental calculation element of:
    a) Conductive/convective/advective, (ignoring fluid advective velocity variations)…. T1 – T2
    b) Radiative…. T1^4 – T2^4
    Thus per law 2, replacement of a momentarily reduced heating regime by a return to a normal higher heating regime will NOT result in continued cooling after application of the increased heating.

    *David B Benson, Reur 437: Peace be with you, and I may comment more later to you.

  47. 447
    Ray Ladbury says:

    BobFJ,
    First, when someone refuses to consider the evidence, and even denies that the evidence exists, what term other than denialist or denier is approproate.

    Second do you at least appreciate the irony of your saying:

    “Thus, since I am not in that category, but merely sceptical of some claims in the AGW debate, I don’t find it to be suitable reading.”

  48. 448
    t_p_hamilton says:

    BobFJ – , let us keep things simple. What year of tamino’s analysis do you think violates thermodynamics in his volcanic lull post?

  49. 449
    BobFJ says:

    Ray Ladbury Reur 447:
    Everyone to their own perceptions of irony, but I find it amusing that you have emphatically contradicted, (denied?), the data such as in the following:

    Australia

    South Australia

    New South Wales

  50. 450
    BobFJ says:

    David B Benson, Reur 437:
    Putting aside Hank Roberts’ 411, where he seems more interested in the success of aerosol reduction measures than in Tamino‘s “volcanic forcings“, it would nevertheless seem that Mauna Loa observations should be free from any NH regional wind-blown concentrations of ANY aerosols that effect insolation transmissivity.
    Thus it is interesting to compare Tamino’s Fig 1 (“volcanic forcing”) with ML transmissivity, where it is available. Also, Tamino only considers volcanos and CO2, and not industrials and ENSO etc. Any comments?


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