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Comments 29901 to 29950:

29901. Tom Curtis at 02:15 AM on 6 May 2015
       Models are unreliable
       

       Klapper @902, science is not arithmetic.  Specifically, in science the numbers represent actual states in the world.  They have meaning.  If you base your arguments on rejecting or ignoring those meanings, as evidently you do, it makes discussion impossible.  In this case, you ignore the fact that empirical values must be set by observation, and consequently (apparently) are distressed that I cite observational papers in support of a claim that a particular number has a particular value (897:1); are distressed that I find it necessary to explain the basic meanings of certain scientific terms, and how that relates to a simple quantitative argument (897:2); apparently are distressed about my pointing to a simple observational proof about the meaning of some data (897:3); and are further distressed by my again having to explain some very basic facts about models and their relation to the world (897:4).  If you were distressed by my explaining these simple facts, be assured I was extremely annoyed that your logic chopping responses made it necessary.  In all my impression is that you are keen to seize on numbers that you think "refute AGW", and are both happy to misrepresent those numbers by willful invalid comparisons (ie, comparing non-equal time periods) to exagerate discrepancies), apparently to leave out numbers that weaken your case (eg, the post 2010 NODC data), and above all, to ignore the meaning of the numbers if understanding it will require you to let go of your argument.  If you wish to stop wasting my time by discussing science you clearly do not understand on SkS, be my guest.

29902. KR at 01:28 AM on 6 May 2015
       Models are unreliable
       

       Klapper - After taking a look at your past comments, I would have to agree with scaddenp. You've apparently decided that CO2 warming, AGW, and all climate modelling are somehow incorrect, and have spent considerable time splitting hairs and decimal points attempting to find some reason to reject them. 

       Most recently you've been rejecting all OHC data before 2005, you've refused to consider recent volcanic activity that has presented a different actual forcing history than was run on the models, both accepted and rejected model drift in the same (contradictory) argument, making impossible claims for perfection by ignoring uncertainties, and have in essence dismissed the fact that models accurately project climate responses to forcings, which can be seen if you use historic forcings (Schmidt et al 2014, also discussed here). 

       In short, you've been rejecting every piece of evidence contrary to your conclusions while misinterpreting data you feel supports them. The best description I've seen of such confirmation bias is Morton's demon - IMO you are so afflicted, and quite frankly it's not worth the time to watch you run in circles. 

29903. RobH at 00:36 AM on 6 May 2015
       2015 SkS Weekly Digest #18
       

       Good grief!  Monkton is now claiming that global warming is a "political issue" and as such, the Pope should not get involved.  Why didnt Monkton tell us this before?  I always though it was a matter of science!

29904. Klapper at 23:02 PM on 5 May 2015
       Models are unreliable
       

       @Moderator #902:

       "...[JH] If you can't stand the heat, it's best you get out of the kitchen..."

       I'm happy to respond/discuss quantitative arguments. They are the only ones from which you learn something. My point was hectoring lectures are a waste of time for both the lecturer and the lecturee. Ultimately our opinions about other people can't change the numbers, can they? Opinion has a place in these technical discussions since oftimes the the numbers are highly subject to interpretation but repetitive judgements on the motive of your opponent is a kind of opinion that doesn't move the discussion forward. If anything they move the discussion backward since you're less likely to pay attention to someone who hectors you.

       I came here as a respite from the monotony of righteous opinion at the Guardian, however here it's not much different. In some ways it's worse in that the technical blogs like Skeptical Science tend to be echo chambers and technical opinion, such as you find it at the Guardian, tends to be more free ranging than here.

       Hopefully this opinion will be allowed by the moderators.

       Moderator Response:

       [JH] I believe it is time for you to move on to a different venue. You have exhausted our patience and have insulted both Tom Curtis and MA Rodgers. Posting on Skeptical Science is a privilege and not a right. 

29905. Klapper at 21:58 PM on 5 May 2015
       Models are unreliable
       

       @Tom Curtis #896:

       I did a similar exercise, but using the quarterly 0-2000 OHC from 2005 to 2014 inclusive, calculating a rolling 5 year trend of delta GJ/yr and converting to W/m^2. The average of the W/m^2 for the rolling 5 year trend was 0.69 (OHC to 2000 metres is 0.56 W/m^2, corrected by .58/.47), very close to your 0.71. The average of a rolling mean of the CMIP5 RCP4.5 ensemble energy imbalance was 0.98 W/m^2, the same as your number. So our numbers agree over the most recent period. They both show the models are on the hot side.

       You are correct the most recent few years the gain in OHC has pickup up.

       I didn't bother reading the last part of your very long winded post #897. It didn't seem to have much quantitative content and if I wanted long hectoring lectures I would be posting somewhere else.

       Moderator Response:

       [JH] If you can't stand the heat, it's best you get out of the kitchen.

29906. Klapper at 21:43 PM on 5 May 2015
       Models are unreliable
       

       @MARodger:

       "...to happily junk 90% of it because it doesn't meet some level of precision..."

       You're putting words in my mouth I didn't say. What I did say and have said all along is that the new ARGO data are much much better. Have you looked at the 5 year data point maps in question? I didn't bother reading your whole post, just as I didn't bother reading the last part of Tom Curtis #897 for the same reason, it's a none quantitative hectoring lecture.

29907. billthefrog at 18:46 PM on 5 May 2015
       Inoculating against science denial
       

       Rob P & Philippe C

       Rob, I've just seen your moderator comment saying enough about vaccines.

       In the interim, however, I had emailed one of the Heads of Department at the London School of Hygiene & Tropical Medicine. As it was a Bank Holiday weekend in the UK, his reply only arrived about 30 minutes ago.

       Obviously you can delete this, or, since it is verbatim from an authoritative source, you might care to let it stand...

        Hi Bill

       I'm sure that sanitation helped, but eradication is dependent on a vaccine. Measles is highly transmissable amongst the non-vaccinated, especially when immunisation rates falls below about 85-90%. Above this, herd immunity makes widespread transmission less likely. I had measles as a kid, but don't seem to remember that sanitation was any worse than at present (probably worse in my house at the moment!).

       Best

       John

       Cheers    Bill F

29908. MA Rodger at 18:26 PM on 5 May 2015
       Models are unreliable
       

       Klapper @898&899.

       It is bizarre that you are happy to present a trace of ΔOHC 1959-2010 @886 then to happily junk 90% of it because it doesn't meet some level of precision that you have decided is required. Indeed, discussing your dismissal of pre-2005 OHC data isn't going to be very helpful if you cannot make a better case for so doing. For instance 'Many orders of magnitude of data density in deep oceans' (which sounds exagerated) can be translated into data uncertainty so it doesn't justify the use of the rubbish bin. Further, inclusion or otherwise of such data is an aside to the central point of this interchange which is the ability of the models to handle the global energy balance.

       I am of the opinion that you are pretty-much wrong on every point being presently discussed (as per @891 for instance). I think scaddenp @895 has probably diagnosed the situation. As you continue to protest that you still hold a valid position, the explanations of why you are wrong become ever more detailed & technical but that will probably not be helpful.

       There are two things required to establish your "The models run hot" assertion. Firstly that model output is higher than measured values. This is possibly true but not to the large extent that you are arguing. And secondly, that the inputs into the model are not the reason for those higher output values. It does appear that the inputs are the reason for the higher model output and to the extent that the models are probably running cool, the opposite of your position.

29909. uncletimrob at 17:24 PM on 5 May 2015
       Week 1 of Denial101x: 14,000 students from 159 countries
       

       @rocketeer  very good, very good!

29910. Klapper at 14:20 PM on 5 May 2015
       Models are unreliable
       

       @Scaddenp #895:

       "... (and why is 2014 in age of Argo relevant?)..."

       I think you're referring to my comparison of the 5 year '68 to '72 inclusive data density map at 1500 m. I could have given you any 5 year period from 2005 on for the ARGO (i.e. 2005 to 2009 inclusive), but it's not important whether I used 1 year or 5 from the ARGO era, or whether it was 2011 or 2014 or whatever. The point is the data density now in the deep ocean is many orders of magnitude better than the 60's to 90's.

29911. Klapper at 14:16 PM on 5 May 2015
       Models are unreliable
       

       @Rob Honeycut/scandenp #894/#895:

       You're complaining not because I didn't utilize the data, which I did, but I think because I don't embrace it as much as I should. It is what it is and I accept that, however, it's not only myself that has doubts about reliability of the data. See these comments from Kevin Trenberth et al 2012:

       "...(XBTs) were the main source from the late 1960s to 2004 but, because depth or pressure of observations werent measured, issues in drop rate and its corrections plague these data and attempts to correct them result in varied outcomes.”

       Certainly the data are far better with the ARGO collecting system was my key point and that analyses using these later systems should carry more weight than '60s/70's/80's analyses.

29912. Tom Curtis at 13:50 PM on 5 May 2015
       Models are unreliable
       

       Klapper @891:

       1)

       ""...because of recent small scale volcanism (also not included in the models).."

       I don't accept that argument."

       I really don't care about your propensity for avoiding inconvenient information.  Recent papers show that the volcanic effect has influenced temperature trends and and TOA energy imbalance.  Thus we have Santer et al (2014):

       "We show that climate model simulations without the effects of early twenty-first-century volcanic eruptions overestimate the tropospheric warming observed since 1998. In two simulations with more realistic volcanic influences following the 1991 Pinatubo eruption, differences between simulated and observed tropospheric temperature trends over the period 1998 to 2012 are up to 15% smaller, with large uncertainties in the magnitude of the effect."

       Haywood et al (2013):

       "Using an ensemble of HadGEM2-ES coupled climate model simulations we investigate the impact of overlooked modest volcanic eruptions. We deduce a global mean cooling of around −0.02 to −0.03 K over the period 2008–2012. Thus while these eruptions do cause a cooling of the Earth and may therefore contribute to the slow-down in global warming, they do not appear to be the sole or primary cause."

       And most directly of all, Solomon et al (2011):

       "Recent measurements demonstrate that the “background” stratospheric aerosol layer is persistently variable rather than constant, even in the absence of major volcanic eruptions. Several independent data sets show that stratospheric aerosols have increased in abundance since 2000. Near-global satellite aerosol data imply a negative radiative forcing due to stratospheric aerosol changes over this period of about –0.1 watt per square meter, reducing the recent global warming that would otherwise have occurred. Observations from earlier periods are limited but suggest an additional negative radiative forcing of about –0.1 watt per square meter from 1960 to 1990. Climate model projections neglecting these changes would continue to overestimate the radiative forcing and global warming in coming decades if these aerosols remain present at current values or increase."

       If you add the -0.1 W/m^2 additional aerosol load after 2000 to the approximately -0.1 W/m^2 from the the discrepancy between modeled and observed solar forcing, you get a CMIP5 absolute value energy imbalance of 0.72 W/m^2 from 2000 to 2010, ie, only 16% greater than observed (Smith et al), and using drift corrected figures the modelled TOA energy imbalance becomes 14.5% less than the observed values.  Forster and Rahmstorf used values from prior to these analyses and so cannot be expected to have incorporated them.  Therefore citing Forster and Rahmstorf  is not a counter argument.  It is merely an appeal to obsolete data.

       2)  With regard to the SORCE data, the situation is very simple.  The SORCE reconstruction is essentially an earlier reconstruction that was benchmarked against PMOD which has been rebenchmarked against the SORCE data.  The effect of that it to shift the entire reconstruction down by the difference between the TSI as determined by PMOD, and that as determined by SORCE.  Consequently the TOA shortwave down radiation is shifted down by a quarter of that value over the entire length of the reconstruction.  Because that shift occures over the entire length of the reconstruction, it means the difference between twentieth century values of the solar forcing and preindustrial values(ie, rsdt(y) minus rsdt(pi), where rsdt(y) is the downward short wave radiation at the tropopause in a given year, and rsdt(pi) is the downard short wave radiation at the tropopause in 1750) does not change, because both the twentieth century values and the preindustrial values have been reduced by the difference between PMOD and SORCE.  Ergo there is no appreciable change in the solar radiative forcing in the twentieth century as a result of the difference.  

       In contrast, for twenty-first century values, the models use a projection so that the difference between (model rsdt minus SORCE value) and the mean twentieth century difference is significant because it does represent an inaccurate forcing in model projections.

       The tricky bit comes about in a direct comparison of TOA energy imbalance.  In determining the "observed" energy imbalance, Smith et al following Loeb et al adjust the satellite observed rsdt, rsut and rlut so that the net value matches the calculated increase in OHC from 2005-2010, and so as to maximize the likilihood of the adjustments given the error margins of the three observations.  Consequently, in all likelihood, they have adjusted the rsdt upward from the SORCE estimate.  Therefore when comparing observations to models we are dealing with two adjustments to rsdt.  First we have an implicit adjustment in the models that results in the radiative forcing being preserved in the models.  This implicit adjustment is equivalent to the average difference between the model rsdt and the SORCE reconstruction.  Secondly, we have another smaller adjustment to the SORCE value that results from the benchmarking of the empirical values.  Because this adjustment is smaller than the first, it generates a persistent gap between the observed and modelled rslut resulting in a persistent difference in the energy balance.

       From the fact that this gap is persistent, the size of the TOA energy imbalance and that temperatures were rising from 1861-1880, it is evident that the gap (and hence the persistent bias) is less than 0.2 W/m^2.  I suspect, however, that it is at least 0.1 W/m^2 and probably closer to 0.2 than to 0.1 W/m^2.

       3) 

       ""....KNMI climate exporer (sic) are strictly speaking top of troposhere"

       What makes you think that?"

       The fact that the graph of rsdt shows a clear downward spike in 1992 (Pinatubo) and another smaller one in 1983 (El Chichon).  That makes sense with increases in stratospheric aerosols, but is impossible if the data is trully from the TOA (rather than the TOA by convention, ie, the tropopause).

       4) 

       ""...CMIP5 forcings are known to be overstated by 0.2-0.4 W/m^2..."

       "...Ergo it is jumping the gun to conclude from this that the models are in error."

       Both above statements cannot be true. The models according to you are (currently at least) in error. If the models are not in error why do they need to correct the TOA imbalance numbers for model drift?"

       By "both of these statements cannot be true", you really only indicateing that you don't understand it.  In fact, everytime you said it in the post above, you were wrong.

       So, lets start from basics.  Climate models are models that, given inputs in the form of forcings produce outputs in the form of predictions (or retrodictions) of a large number of climate variables.  When you have such a model, if you feed it non-historical values for the forcings, it is not an error fo the model if it produces non-historical values for the climate variables.  So, when we discover that forcings have been overstated for the first decade and a half of the twentyfirst century, we learn absolutely nothing about the accuracy of climate models.  We merely rebut some inaccurate criticisms of the models.  It follows that the first sentence does not contradict, but rather provides evidence for the second.

       With regard to model drift, had you read the relevant scientific paper (to which I linked) you would have learnt that it is impossible to determine without exhaustive intermodel comparisons whether or not drift is the result of poor model physics, too short a run up time or poor specification of the initial conditions.  Only the first of these counts as an error in the model.  Ergo, you cannot conclude from this that because of model drift, the models are flawed.  All you can conclude is that, if you accept that the model drift exists, then you ought to correct for it and that uncorrected model projections will be rendered inaccurate by the drift.  Now here you show your colours, for while you steadfastly refuse to accept the dift corrected TOA energy imbalance figures as the correct comparitor, you want to count model drift as disproving the validity of models.  That is an incoherent position.  Either the models drift and we should compare drift adjusted projections to emperical observations, or they don't drift in which case you can't count drift as a problem with the models.

29913. Tom Curtis at 10:50 AM on 5 May 2015
       Models are unreliable
       

       Klapper,  I was looking at the NODC 0-2000 OHC data as a check on the empirical data.  Year by year, here is the comparison, with "world" equalling the 0-2000 meters adjusted by a scaling factor based on Smith et al. (The scaling factor is to multiply by 0.58/0.47, or equivalently, divide by 0.81.)

       

       For reproducibility, the 2005 value is based on the difference between the 2005.5 and 2006.5 OHC, which represents therefore the gain in OHC between those periods (ie, the gain in OHC for 2005).  Overall, there is an average difference between the models and observation in this period of 0.12 W/m^2.

       For comparison, here are the five year means over that period shown in the graph:

       Period_____ | CMIP5 | Obs | Diff
       2005-2010 | 0.91 | 0.67 | 0.24
       2006-2011 | 0.95 | 0.42 | 0.53
       2007-2012 | 0.99 | 0.58 | 0.41
       2008-2013 | 1.02 | 0.83 | 0.20
       2009-2014 | 1.02 | 1.02 | 0.00
       Mean______ |0.98 | 0.71 | 0.27

       The means of the five year means exagerate the discrepancy because they count the middle (low) values more often than the high endpoints.

       In any event, it is clear that when you say "The discrepancy from observations to models is currently 48% (0.90 to 0.62 W/m^2 TOA energy imbalance)" it is not true.  The discrepancy, if we take the latest five year mean is in fact 0%.  Of course, a better observational basis may restore that discrepancy.

29914. scaddenp at 08:20 AM on 5 May 2015
       Models are unreliable
       

       Klapper - all measurement systems have issues. The question to ask is what can be determined from measurements available and to what accuracy. This is dealt with in a number of papers, particularly here. See also supplimentary materials in the Levitus papers on OHC content. What do you perceive to be the errors in this analysis?

       Your earlier response on dismissing pre-Argo, simply pointed to sparcity of deeper data (and why is 2014 in age of Argo relevant?). To dismiss 0-700 warming because 700-2000 is sparce however means having a plausible mechanism for 700-2000 cooling while 0-700 heats.

       Looking over your posting history, it appears to me that you have made an a priori choice to dismiss AGW and seem to be trying to find something plausible, anything!, for dismissing inconvenient data rather than trying to understand climate. If this is correct, then do you have an idea of what future data might cause you to revise your a priori choice?

29915. rocketeer at 07:23 AM on 5 May 2015
       Week 1 of Denial101x: 14,000 students from 159 countries
       

       The enrolment hockey stick!

29916. Rob Honeycutt at 07:21 AM on 5 May 2015
       Models are unreliable
       

       Klapper... Don't throw the baby out with the bathwater just because he's not reached puberty yet.

29917. CBDunkerson at 05:00 AM on 5 May 2015
       2015 SkS Weekly News Roundup #18B
       

       Arctic researchers missing, presumed dead.

       Apparently, they (Marc Cornelissen & Philip de Roo) were on a trip to survey the remaining multi-year ice north of the Candaian arhcipelago (projected to eventually be the 'Last Ice' remaining in the Arctic) when they encountered unexpectedly thin ice and their sled broke through and sank.

29918. Klapper at 04:17 AM on 5 May 2015
       Models are unreliable
       

       @CBDunkerson #892:

       I used datasets compiled using XBD inputs. As you can see my graph shows ocean heat content changes going back to 1959 (pentadal dataset starts 1957, so a centred 5 year trend first occurs in 1959. However, given the XBT have problems with depth resolution, based on sink rates, they are nowhere near as good as the ARGO floats. Unfortunately the ARGO network only reach a reasonable spatial density in 2004 or 2005.

29919. CBDunkerson at 22:37 PM on 4 May 2015
       Models are unreliable
       

       Klapper wrote: "I don't want 'perfect data', I want the best data."

       Great! So what pre-Argo data is there which is better than the XBT results? None? Then guess what "the best data" for that time period is. :]

29920. uncletimrob at 21:07 PM on 4 May 2015
       2015 SkS Weekly News Roundup #18A
       

       Of course I can only speak by relaying the conversations I have with my colleagues who are tertiary educated, have families, are articulate and concerned about what they will leave for their children and grandchildren, but the concensus at my workplace - a school - is that Tony Abbott has it wrong, and that the carbon tax whilst unpalatable was a better bet.

        Of course the mining industry here in OZ - coal and iron ore principally - has a large input to the economy, so one (coal) is a direct fail for Abbott and "direct action", and the other (iron ore) probably drives the downturn in coal (if I read the various indices correctly).

       Just a cheapie from a grandparent, so take it as you will ....

       Tim

29921. Klapper at 17:13 PM on 4 May 2015
       Models are unreliable
       

       @Tom Curtis #889 & 890:

       "... It follows that minor discrepancies over more recent periods between model predictions..."

       I don't think they are minor, I think they help explain the recent lack of surface temperature gain in the observations compared to that projected by the models. The discrepancy from observations to models is currently 48% (0.90 to 0.62 W/m^2 TOA energy imbalance).

       "...because of recent small scale volcanism (also not included in the models).."

       I don't accept that argument. Forster and Rahmstorf 2011 did multivariate regression on the effects of TSI, ENSO and AOD, albeit against surface temperature, not TOA imbalance, but their Figure 7 shows essentionally no significant effect form aerosols after the mid-nineties (as least compared to ENSO and TSI). You'd be better off to include ENSO in your arguments than small volcanoes as I doubt the latter come close to the effect of the former. I suspect that's your next argument, ENSO deflated the observed TOA imbalance in the first decade of the 21 first century, which the models didn't include.

       

       "...Slight changes in a forcing consistently applied over the whole duration will not effect the anomaly and therefore are not relevant.."

       That's a rather astounding statement given it's untrue if you mean that changes in forcing won't affect the delta in the temperature anomaly.

       "...You will notice that the multi-model mean is about 0.2 C less than (ie colder than) the observed values..."

       Irrelevant. The forcing changes the warming rate, not the baseline which is dependent on the starting temperature/starting heat content. The warming rate in the models is essentially the same as the observations for surface temperature, yet the magnitude of the solar input appears to be approximately 0.85 W/m^2 too high (if we can believe the SORCE TSI reconstruction), in the CMIP5 model inputs. This is a serious issue you chose to treat as if it's not important but it is. Either the models are using the wrong input, or the SORCE 20th century TSI reconstruction is wrong.

       "...Further note with respect to your "models always run hot" comment on another thread, in this and many other cases, they run cold..."

       Calculate the SAT trend in all of the models and tell me what percentage run "hot" and what percentage run "cold"? Not many of them run cold and we shouldn't waste our time on sematic arguments when the ensemble mean is consistantly above the observations for TOA imbalance. Look at your own table above. The model forcing is higher than the observations in all but 1 of 10 period comparisons to the observations (5 CMIP5, 5 CMIP5 "adjusted").

       "....KNMI climate exporer (sic) are strictly speaking top of troposhere"

       What makes you think that? Maybe there's an issue with translation from Dutch but the description in the CMIP5 "standar output" document for the "rlut" variable is:

       "at the top of the atmosphere (to be compared with
       satellite measurements)"

       And if the "rsdt" varible was Top of the troposphere, it should be lower than the TSI reconstruction, not higher, as some incoming LW would not make the tropopause due to absorption in the stratosphere.

       "...(Note again, such a constant offset of a forcing would not affect appreciably changes in anomaly temperature values.)..."

       Once again, we are not talking about offsetting forcings, I agree it doesn't matter, we are talking about a difference in the net between input and output TOA, which do affect anomaly values. It is not true the net forcing in the models is the same as the observations.

       "...CMIP5 forcings are known to be overstated by 0.2-0.4 W/m^2..."

       "...Ergo it is jumping the gun to conclude from this that the models are in error."

       Both above statements cannot be true. The models according to you are (currently at least) in error. If the models are not in error why do they need to correct the TOA imbalance numbers for model drift?

       I think my next step will be to compare the CMIP5 model TSI input to the ACRIM TSI reconstruction.

29922. Tristan at 16:40 PM on 4 May 2015
       Inoculating against science denial
       

       cormagh - What is the myth, and what is the fallacy?

29923. cormagh at 16:14 PM on 4 May 2015
       Inoculating against science denial
       

       If you're trying to discover what myths might distort the science, why don't you start with The Apocalypse. This comment is directly referencing the article's position, "explain the fallacy employed by the myth." 

29924. Tom Curtis at 11:20 AM on 4 May 2015
       Models are unreliable
       

       For completeness, here are the absolute discrepancy at top of Troposphere, the Smith et al  corrected values and the Smith et al observed values for the periods listed in Smith et al for comparison:

       Period | CMIP5 | CMIP5 (Smith) | Obs (Smith
       1861-1880 | 0.29 | xxxx | xxxx
       1961-2010 | 0.56 | 0.36 | 0.33
       1971-2010 | 0.67 | 0.46 | 0.48
       1993-2010 | 0.91 | 0.68 | 0.59
       2000-2010 | 0.92 | 0.73 | 0.62
       2005-2010 | 0.90 | xxxx | 0.58

       The factors in play explaining why there is a difference between the Smith et al CMIP5 values and the CMIP 5 absolute values are:

       1)  The CMIP 5 values as downloaded from the KNMI climate exporer are strictly speaking top of troposhere (or tropopause) values where as Smith et al may have obtained actual Top Of Atmosphere values.  The primary differences between top of tropopause and TOA values is that TOA solar values would be slightly higher, as would outgoing longwave radiation (due to the effect of the stratosphere).

       2) Smith et al are corrected for model drift.

       The primary factors relating to the difference between observed values and the absolute CMIP5 values are:

       a)  CMIP5 forcings are known to be overstated by 0.2-0.4 W/m^2 relative to anomaly values from the late 1990s onward due to low solar and background volcanic effects.

       b) CMIP5 absolute values of solar forcings are known to be overstated relative to observations by an unknown (by us) amount.  The amount is unknown in that in benchmarking values for the observations, all three relevant factors may have been adjusted, so that the solar values may have been greater than those from SORCE TIM, but would not have been less than the unadjusted SORCE-CMIP5 discrepancy of about 0.8 W/m^2.  This could account for the ongoing high bias of CMIP-5 absolute values.  (Note again, such a constant offset of a forcing would not affect appreciably changes in anomaly temperature values.)

       c) CMIP5 absolute values apparently need correction for model drift, although I cannot do more than note the stated necessity by relevant experts and refer you to the relevant literature on this point.

       Combining these three factors we have an explanation for the increased discrepancy in the 21st century that explains from half to all of the discrepancy observed.  We have a further explanation that potentially over-explains the persistent high bias of CMIP-5 absolute values.  Finally we have a factor that essentially eliminates the discrepancy prior to the 21st century.  If anything, given all this, the models are running too cold relative to known discrepancies.

       The important point is not that we have these explanations.  With further refinement of observations, the correction factors they imply are likely to shift so that the models are running hot again, or colder.  The important point is that the models have run within error of observations, and that there are factors that can explain both short term increases in the discrepancy and long term persistent features.  Ergo it is jumping the gun to conclude from this that the models are in error. 

29925. Tom Curtis at 10:46 AM on 4 May 2015
       Models are unreliable
       

       Klapper @888:

       1)  Why are you focusing on the least germain part of my comment?  Surely the important thing here is the change in the RSDT discrepancy over the last 15 odd years.  The discrepancy over the full period is relevant only in illustrating that models uses observational data of forcings that are approximately 10 years out of date (of necessity given the time it takes to set up and run models, and delays related to publication time).  It follows that minor discrepancies over more recent periods between model predictions and up to date data is as likely to be due to the updating of the data as to any problem with the models.  In particular, over the last decade or so, we know that model forcings are too large relative to recent observations because of an unpredicted very low solar minimum and recent low solar activity, and because of recent small scale volcanism (also not included in the models).  That you have run this entire argument without ever acknowledging this fact, even when it is pointed out to you shows deliberate avoidance.

       2)

       "How do you explain with this alleged massive error over the whole of the 20th century, they manage to replicate surface temperature as well as they do?"

       More specifically with relation to comment my point (1), models predict changes in temperature anomalies.  Slight changes in a forcing consistently applied over the whole duration will not effect the anomaly and therefore are not relevant.  They are relevant to absolute temperature values, as shown in the side box to this graph:

       

       You will notice that the multi-model mean is about 0.2 C less than (ie colder than) the observed values.  The primary effect of the 0.8 W/m^2 difference in solar insolation would be to reduce that further by a small amount.  (Note as an aside that the absolute value of the GMST is not well constrained by observations.  I have seen values of 14 C and 15 C quoted based on different temperature series.  Further note with respect to your "models always run hot" comment on another thread, in this and many other cases, they run cold.  It is only that deniers cherry pick only those cases where the models "run hot" for their criticisms.)

       3)  I have clearly linked to Smith et al, who in turn clearly cited Sen Gupta et al on climate drift.  I am not going to try to explain it further as I do not understand it well enough.  I am going to acknowledge that the relevant experts think it a significant factor and correct for it, and note the corrected values.  You on the other hand seem intent on holding it dubious because you couldn't bother doing your own homework. 

29926. Klapper at 09:53 AM on 4 May 2015
       Models are unreliable
       

       @Tom Curtis #887:

       "... In the late nineteenth century, the discrepancy is about 0.8 W/m^2"

       "...Even if we align the two estimates over the late 20th century..."

       Yes, the models use a TSI history that is consistently 0.8 to 0.9 W/m^2 higher measured at the earths surface (or 3.2 to 3.6 watts/m^2 of total solar flux) compared to the Source TIM-adjusted reconstruction. How do you explain with this alleged massive error over the whole of the 20th century, they manage to replicate surface temperature as well as they do?

       Is this the reason behind the "model drift correction" employed by Smith et al you alluded to earlier?

29927. Tom Curtis at 08:18 AM on 4 May 2015
       Models are unreliable
       

       Klapper @886, very briefly, the CMIP5 RSDT from KNMI is consistently larger than the equivalent estimated value from the SORCE TSI reconstruction currently considered to be the best TSI reconstruction by the IPCC.  In the late nineteenth century, the discrepancy is about 0.8 W/m^2.  Even if we align the two estimates over the late 20th century, what we get is an increasing overestimate by CMIP5 with time:

       

       So, the most obvious thing about your diagram is not that the discrepancy becomes largest where the observations are most accurate, but that it becomes largest where the solar component is known to be over represented in the models.  That alone accounts for approximately 0.2 W/m^2 of your discrepancy, and possibly more depending on how accurate the difference between model and observed solar input is over the full record.

       This, of course, continues to ignore the effect of the large number of small volcanoes in the early twenty-first century that are observed, but not included in the CMIP-5 data which will account for yet more of the discrepancy.

29928. Klapper at 03:49 AM on 4 May 2015
       Models are unreliable
       

       @Rob Painting #882:

       Here is a graph I created by extracting from KNMI explorer the Watts/m^2 down and up (SW and LW) and calculating the net energy imbalance from these absolute variables (dashed black line, variables are rlut, rsut, and rdst). The "Global" (dark blue line) net from observations is really a fudge by assuming that OHC (which is derived from the Pentadal 0-2000) is 80% of the global (as per Tom Curtis' comment). Obviously that's not true over time but it suffices as a cross-check on how far from the observations the models might be deviating using this 80% factor to calculate a facsimile for global energy imbalance. The light blue line is the 0-2000 OHC from NODC pentadal, delta ZJ over 5 year running linear trend with ZJ/year converted to W/m^2 global basis.

       

       There is a difference between this and the Smith et al figure posted on the other thread by Tom. I think the difference may be what Tom alluded to as adjustments for "model drift" in the Smith et al TOA model net imbalance. Then again, I could have made some mistake in my processing.

       If I am correct the first observation I would make is that the better quality data we have on observations, the bigger the spread between OHC energy input and TOA model energy imbalance.

29929. One Planet Only Forever at 01:51 AM on 4 May 2015
       2015 SkS Weekly News Roundup #18B
       

       In addition to the mentioned benefits of 'leadership' from California, the global community has benefited from the leadership of the European Community on matters like reduced sulphur content in diesel.

       In the late 1970s the unacceptability of sulphur in diesel fuel was globally understood. However, the US deliberately delayed implementing reduced sulphur content requirements in order to obtain an economic advantage in trade with Europeans or anyone else who did implement lower sulphur requirements . The US requirements continue to lag behind what can be accomplished (European developed diesel technology is still 'ruined' by the quality of fuel in the US).

       There are many other examples of the deliberate delay of action by the US in any area where temporary economic advantage can be obtained by such delay. That is why the US (and Canada and Australia), increased emissions from 1990 to 2005 compared to the Europeans holding emissions fairly constant through to 2005 (and it is why the US proposes its reductions relative to its 2005 levels rather than 1990 levels which were 17% lower).

       The real problem to overcome is the profitability and popularity of political and economic leadership action that appeals to desires that it is possible to understand are unacceptable, or creates fear to garner support for actions that can be understood to be unacceptable.

29930. RobH at 01:28 AM on 4 May 2015
       2015 SkS Weekly News Roundup #18B
       

       Those with long memories will recall that it was California that turned the world onto cheap and reliable electronic fuel injection for consumer vehicles.  As of Governor Brown's setting a high bar for reducing carbon emissions, so did California in the 60s when an exceptionally high bar was set for vehicle exhausts in that state when air pollution was becoming a crippling issue for cities like LA.  Volkswagen took up the challenge with Bosch being given the job of designing a cheap fuel injection system that has now universally replaced carburettors. Of course other companies had to follow in the footsteps of Bosch.  We have California, VW and Bosch to thank for what we have today.  I can see California once more putting the challange to industry which will feed through to the rest of the world.

29931. Klapper at 01:20 AM on 4 May 2015
       Models are unreliable
       

       @Klapper #884:

       I see my dropbox links do not work, which I suspected when I could not see the images in the preview. Back to the drawing board.

       Moderator Response:

       [RH] You might try http://tinypic.com

29932. Klapper at 01:19 AM on 4 May 2015
       Models are unreliable
       

       @Rob Painting #882:

       Graph as discussed. TOA Energy imbalance net from CMIP5 model ensemble variables as discussed above.

       

        

       

29933. Leto at 22:29 PM on 3 May 2015
       2015 SkS Weekly News Roundup #18A
       

       Very sad to hear, chriskoz,but sadly no surprise.

       This is not a rhetorical question... Do you think many people seriously believed that TA's direct action was meant to achieve anything?

       I see the right-wing media and a few TA fans playing along with the charade, but I always imagine they know better deep down. After all, TA got into power on a denialist wave, within his own party, around the time of 'Climategate', and he knows that is where his fanbase still is.

       I see scientists and environmental groups declaring Direct Action to be a doomed strategy of paying the polluters to achieve very little. Most Liberal voters could not care less about the scientific details, or they woudln't have let an antiscience prime minister come into power in the first place.

       Are there really people who actively argue with conviction that this is a good idea and that it is going to have a useful effect (on a per capita basis) on global warming? I see it more as a foil with which they can deflect criticisms from the left, as in: "Global warming is rubbish, and even if it turned out to be real, we're doing our bit anyway, so stop complaining.. "

       Moderator Response:

       [AS] For the benefit of non-Australian readers, "TA" is Tony Abbott, the Australian Prime Minister (I assume). 

29934. chriskoz at 21:51 PM on 3 May 2015
       President Obama's Anger Translator on Climate Change
       

       The last sentence by Luther to Michelle "he's crazy" creates an ambience of joke around Obama rant about "stupid irresponsible snowball throwing...". Obama must have orchestrated it to soften the ensuing conflict with Sen. Inhofe and that's understandable.

       But the issue is not a joke (at least for me), therefore Obama should have left the rant without adding any "craziness" to it.

29935. chriskoz at 21:03 PM on 3 May 2015
       2015 SkS Weekly News Roundup #18A
       

       More on the Carbon Reduction Auctions in Australia. Energy Regulator said the contracts were awarded to 43 contractors covering 144 projects.

       “The majority applied under sequestration methods, and landfill and alternative waste treatment methods.”

       I was scratching my head thinking: what sequestration methods, CCS yet to be developped? But govs have explained the detail:

       A$660 million of contracts to deliver more than 47 million metric tons of abatement. It paid an average A$13.95 per ton to companies for projects including capturing methane from pig manure, planting trees and managing fires in savanna grasslands.

       Well, now I understand: my "Carbon Reduction" tax dollars went to the projects that have little (if anything) to do with FF emission reduction. Managing fires have nothing to do with reduction of FF emissions. Those fires consume carbon that's mostly couple decades old (forrest understory) or at most couple 100s y old (if some old trees are burned), while 300-400m y old coal burning continues unabated. No wonder, because coal is "good for humanity". Or pigs' emission sequestrations... Well, our govs are trying to get away with that travesty which amounts for deliberate misleading of taxpayers who don't understand the difference between the fossil fuel emissions (where the money is supposed to go) and pigs' emissions (where the money is going) which as a mitigation effort is just a joke IMO. Someone hopefully will pick it up and duly explain to the australian public, whose money is being wasted.

29936. Philip Shehan at 20:45 PM on 3 May 2015
       The climate 'hiatus' doesn’t take the heat off global warming
       

       England's paper has (predictably ) been portrayed on Andrew Bolt's blog as a backdown requirng an apology

       "Warmists who denied the pause now claim to explain it"

       LINK

       While I understand that the paper is a useful in explaining what the consequences are if there is indeed a pause, that is a long way from being established.

       Gistemp data since 2000 from the Skeptical Science trend callculator::

       
       Trend: 0.09 ±0.13 °C/decade

       
       For “two decades” it is

       
       Trend: 0.12 ±0.09 °C/decade

       
       So there is a warming trend, with a headline value lower than that for the statistically significant warming trend from 1979:

       
       Trend: 0.16 ±0.04 °C/decade

       
       But the error margins for the period since 2000 mean that for the short period there is a 95% chance that the trend is as much as warming 0.22 °C/decade or a cooling trend of as much as -0.04 °C/decade.

       
       In fact both the shorter periods support the null hypothesis.

       
       That is, they are statistically not distinguishable from the warming trend beginning in 1979.

       
       null hypothesis

       
       noun

       
       1.(in a statistical test) the hypothesis that there is no significant difference between specified populations, any observed difference being due to sampling or experimental error.

       Moderator Response:

       [RH] Activated link to fix page formatting.

29937. Rob Painting at 20:43 PM on 3 May 2015
       Models are unreliable
       

       And the climate model vs observation (black solid line) of ocean heat content from the IPCC AR5 is shown here:

        

29938. Rob Painting at 20:41 PM on 3 May 2015
       Models are unreliable
       

       The uncertainties in Earth's total heat content data, 93% of which is ocean heat content, is shown in the image from the IPCC AR5 below:

        

29939. MA Rodger at 19:27 PM on 3 May 2015
       Models are unreliable
       

       Mal Adapted @870.
       You write "I'm not a biblical scholar, but I don't recall seeing any estimates of error margins in that book..."
       My understanding of Leviticus is that it is entirely about defining error and what happens when any such error occurs. Within an approach to error such as laid out in Leviticus, the concept of there being 'error margins' disappears within a binary reality: either there is error or there is not error :-)

29940. MA Rodger at 19:24 PM on 3 May 2015
       Models are unreliable
       

       Klapper @879.

       There is plenty of advice on where you can up-load images that is easily found on-line, for instance here. Many require nothing more than an e-mail, a user name & a password. For instance (and I mention it as an exemplar rather than recommend it) this website allowed me to upload an image in less that a minute. I would have displayed the resulting image in-thread but the image to hand that I up-loaded is political in nature.  

29941. bozzza at 09:57 AM on 3 May 2015
       Overlooked evidence - global warming may proceed faster than expected
       

       Carbon in soils is another thing that seems as poorly understood as cloud feedback.

29942. Peter Lloyd at 05:34 AM on 3 May 2015
       Overlooked evidence - global warming may proceed faster than expected
       

       It is good to raise this issue of single study syndrome because far too many grand conclusions are drawn from just one new piece of evidence or from yet one more model.

       It also highlights the point that there is no clear conclusion of the individual, let alone cumulative, effects of both negative and positive feedback mechanisms and how they offset each other.

       It's also good to see a recognition of how the impact of clouds is so poorly undertood and yet potentially significant

       It can't be said too often that new pieces of work that authors and commentators may  exaggerate the significance of for obvious reasons, are frequently challenged by later pieces of work but that challenge is not always examined and recorded.

       Keep on being sceptical might be a good mantra

29943. jja at 03:49 AM on 3 May 2015
       2015 SkS Weekly News Roundup #18B
       

       I have decided not to use the Luntz' term "climate change" except to describe global warming related effects.  The cause is Global Warming.  The effect is climate change.
       
       Why anyone would decide to go along with a denialist talking point is beyond me.

       Moderator Response:

       [JH] Scientists had used the term "climate change" long before Luntz decided it would be preferrable to "global warming" for political communications purposes. The term "climate change" is not a "denialist talking point."

29944. One Planet Only Forever at 02:06 AM on 3 May 2015
       2015 SkS Weekly News Roundup #18B
       

       This New York Times article refers to a recent study and report led by Erich M. Fischer evaluating the increased probabilities of extreme weather events for different levels of increase of global average surface temperature.

29945. PhilippeChantreau at 01:10 AM on 3 May 2015
       Inoculating against science denial
       

       Feel free Tristan. Rob, vaccines are mentioned at length in the OP. Although it has to do more specifically with the false link to autism, and it is given as an illustration for the ideas developped in the post, I'm not sure it's fair to expect the thread to be free of comments about a significant aspect of the OP.  I will nonetheless respect your request, despite my intention of further investigating the claim that measles dropped to insignificance because of sanitation, a claim of which I am highly skeptical. Thank you for allowing as much as was said.

29946. Tristan at 17:11 PM on 2 May 2015
       Inoculating against science denial
       

       Philippe, with your permission, I'd like to quote that in full on my FB timeline (although I'll remove the references to the above poster).

       Moderator Response:

       [Rob P] No more about vaccines thanks. Any further comments will result in deletion.

29947. PhilippeChantreau at 16:18 PM on 2 May 2015
       Inoculating against science denial
       

       Really? Why should I do your work?

       In 1966, the year I was born, a massive campaign of containment and eradication was launched in Central and West Africa against smallpox. In 4 years, the disease was essentially eradicated, before there was any chance to improve infrastructure and sanitation in any significant way. Eradicated in 4 years. One does not realize what a feat that was in these spoiled, worry free days of the 21st century. As of the mid-2000s, the WHO determined that the Republic of the Congo (Congo-Brazza) still had only 0-25% of its population using improved sanitation, yet the disease was eradicated there as well as in other countries part of the campaign. Other countries aren't that much better on the sanitation side, 40 years after the campaign. Some other countries, such as Gabon, have a rather small population, which makes access to sanitation easier.

       I still bear on my shoulder the mark of the smallpox vaccine received in Brazzaville in the early 70s. I'm proud of it. In the former Zaire, smallpox eradication took all but 41 months, despite tremendous challenges in infrastructure and, you guessed it, sanitation. By an ironic and cruel reversal of circumstances, polio, eradicated as well as smallpox, is now on the rise in RDC because of imported cases. Perhaps some of the westerner fruitcakes who don't "believe" in vaccinations, who knows?

       http://www.who.int/water_sanitation_health/monitoring/africasan.pdf

       http://www.ncbi.nlm.nih.gov/pubmed/22188930

       Interestingly, in the Congo Brazza, smallpox vaccination conferred also some immunity to monkey pox, which is now on the rise because of the end of massive immunization campaigns. The risk of developing the disease is 5 times greater for non immunized subjects:

       http://www.pnas.org/content/107/37/16262.full

       I'm done wasting my time with you, it is obvious that you are clueless, if you were not, you would already about all this. The sincerity you claim obviously does not apply to pet theories of yours. What we really need in this world is a vaccine against Dunning-Kruger.

       Moderator Response:

       KC: ad-hom snipped.

29948. Straight Talkin at 14:56 PM on 2 May 2015
       Inoculating against science denial
       

       Just to expand a bit. Some years ago I was in almost convinced by the climate contrarians that we weren't causing the problem. Then I found skeptical science and it systematically demolished the climate deniers arguments. So I understand that arguments can sound convincing even when they are not really based on a whole picture scientific analysis. I always seek to get to the bottom line. I am not a conspiracy theorist, nor am I naive enough to not think that vested intersts do sometimes win out in corrupting situations, and have the capacity to have a corrupting influence on the scientific community and society generally. As the old quote goes 'Eternal vigilance is the price of freedom'

29949. Straight Talkin at 14:39 PM on 2 May 2015
       Inoculating against science denial
       

       Philippe Chantreau, You misunterstood my point about scurvy. I know that nutrition i.e. Vitamin C erradicated deaths from scurvy. The point I was makling is that long before vaccinations for measles were introduced the reductions of deaths from measles tracked perfectly with the reductions in deaths from scurvy as nutrition improved, to the point of insignificance.

       My point regarding consensus is that although it is always worth taking into account, it should never be placed on a holy pedastal.
       Could you direct me to research that demonstrates you statement 'It is interesting to note that diseases that lend themselves to immunization regress enormously in these countries when people are immunized, even in the absence of significant progress in sanitation.' ?
       I am always willing to change my viewpoint based on new and convincing information.

29950. PhilippeChantreau at 14:23 PM on 2 May 2015
       Inoculating against science denial
       

       Well I guess, since this is hinted at in the OP, it is on topic. It is interesting to see how Straightalkin formed an opinion about Measles by linking with scurvy when the 2 diseases have totally different pathophysiologies, and can truly not be comapared.

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