Bishop Hill Apples, oranges, whatever...
Jul 30, 2015 Climate: Models Climate: Surface A new paper by Kevin Cowtan et al claims that the divergence of models and observations is not as big as we thought.
Global mean temperatures from climate model simulations are typically calculated using surface air temperatures, while the corresponding observations are based on a blend of air and sea surface temperatures. This work quantifies a systematic bias in model-observation comparisons arising from differential warming rates between sea surface temperatures and surface air temperatures over oceans. A further bias arises from the treatment of temperatures in regions where the sea ice boundary has changed. Applying the methodology of the HadCRUT4 record to climate model temperature fields accounts for 38% of the discrepancy in trend between models and observations over the period 1975-2014.
It sounds a bit odd to me, but I don't have a copy as yet, so I'm going to hold off further comment for the minute. One assumes though that even if the findings are sound the divergence of satellite temperatures from the models is unaffected.
Bishop Hill
Thanks to readers who have sent the paper along. Here's what the authors have done:
Global averages of the observational temperature records are typically compared to near surface air temperature from an ensemble of climate model simulations...most studies have used the surface
air temperature field from models rather than blended land-ocean temperatures...A true like-with-like comparison would involve blending the air and sea surface temperature fields from the models in a manner consistent with the observational records. The purpose of this work is to evaluate the impact of comparing air temperatures from models with the blended observational data, and to establish guidelines for the determination of blended temperature comparisons.
This seems unexceptionable to me.
Reader Comments (71)
Cowtan is the antithesis of a scientist, he's forever whitewashing black swans to make the facts fit the hypothesis.
Sounds a bit like desperately trying to cover the mess climate "science" has got itself in to! The discrepancy between what the climate "scientists" (AKA alarmists) have predicted (so called projections) is now huge, it is beyond any real scientific explanation. So they fall back on the old trusted pseudo-science!
Three points:
1. As someone mentioned to me on Twitter, they tried really hard and could only explain "38% of the discrepancy in trend between models and observation"
2. In Mann-speak, the "pause" can now be indicated as "estimates of recent surface temperature evolution fall at the lower end of climate model projections" or "the discrepancy in trend between models and observations over the period 1975-2014"
3. Somebody ought to tell Cowtan and Mann that the "discrepancy" they describe is 39 years long, and this makes it relevant for multidecadal climate change.
How gullible do they think we are? We aren't some starry eyed student who'll swallow this.
The simple fact is that even the young naive, gullible interns who BIG ENVIRONMENT use to line their own pockets have stopped swallowing the non-science and are starting to squeal about the abuses of power. We've seen this with Pachauri, now at the EPA.
There's a culture of using a never ending stream of the gullible to get their own way. Usually by older men.
Climate of Harassment: EPA sexual ‘predator fed a steady diet of interns’ – Sparks fly as EPA chief under fire at House Hearing
All of Cowtan and Way's output will be forever tainted by their previous failed attempts to explain away the shortcomings of the models. These two will never be taken seriously as legitimate scientists.
So is the 38% of the discrepancy to be addressed by models being adjusted to run cooler or from adjusting the thermometers to measure higher? Or is this a declaration that models are not modelling what the the temperature records have measured?
If the former then retrofitting history should be a hoot and if the latter is true then would I not be wrong in thinking that the word 'science' in the phrase 'climate science' is being used inappropriately, how could none of the great minds involved not realised this?
Calculation of 'greenhouse effect' magnitude is the difference between estimates of surface* and surface air temperatures.
Apples, oranges, whatever... Doesn't matter: only magnitude counts.
*Earth with no radiative gasses.
MikeHaseler
yeah.... Climate of Harassment.... the progressive media have been ignoring the steady stream of appalling antics perpetrated by officials at the EPA and environmental bureaucrats / embedded activists at a state level. I presume that the status of eco-twattery as being notionally outside party politics and therefore morally unassailable plays a pivotal role in this. I'm feeling a bit irked just having read the UK's official Climate Handbook
The validation word is MIA too... perhaps too strong and prone to attracting somewhat more "robust analysis" than is intended... Desperation is one word I suppose .... I think the whiff of mendacious misdirection and deflection is wafting from this - surprise - not.
These fake 'studies' come like a production line of rebuttals, which is hardly surprising because that's exactly what they are intended to be. Record arctic sea ice, failed computer models, no increase in 'extreme' weather and of course the pause....all face constant revision through bogus pal-reviewed papers designed solely to prop up the failed theory and keep the gravy train on the rails. Laughable stuff, really.
Ask yourself when was the last time one of these studies concluded something (anything!) that worked 'against' agw? Answer: never. That's because it's pure propaganda.
I remember the days when the physical sciences followed certain well established paths to the truth. Often beginning with an hypothesis, followed by a mathematically based theory or model, then progressing on to empirical data collection and/or experimental verification. Current climate science never seems to get beyond the model stage, and the models are tweeked and adjusted in an attempt to arrive at the right politically acceptable result. I am sure that Lewis Carol would have found a very readable story, somewhere in this confusing mess.
All they have identified is yet another reason why the satellite measurements are more to be trusted over the last 35 years.
These studies really do show the critical weakness in Climate Science - the utter lack of climate scientists to challenge the work of their colleagues.
Physics, biology, chemistry, all advance because other scientists in those fields refuse to just accept papers written by others. Often that might be for "bad" reasons - professional jealousy, competition for grants, unwillingness to let another scientist get any glory - and sometimes it is because they seek the truth, but the result is that papers have to stand up to rigorous and constant challenge.
All we see in climate science though is a defence of every paper, however poor.
tomo: Re: "Climate of harassment".
The penny dropped when I realised that the only way the climate extremists argue is one based on "authority". But when you get down the the nub, what they are doing is abusing that authority, abusing their power for their own gratification. It's as true of those who wrote papers just to stop sceptic stuff getting into wikipedia as it is of Pachauri or the EPA letch.
Has anyone else noticed that despite all the money and time wasted on trying to explain the lack of warming, none of the global warming experts has rexamined their assumption that there SHOULD be any global warming.
Trying to find evidence to support your conclusion, is not good science. Jumping to conclusions,without evidence, is for jumped up scientists. Luckily for them, it is not their money or lives being wasted.
golf charlie: "none of the global warming experts has rexamined their assumption that there SHOULD be any global warming".
Have I noticed? Of course I noticed, that's why as far back as 2007 I was getting people to discuss the global warming pause, because the pause proves that any trend from natural variation is as large as the projected warming.
And once you understand that these academics own predictions force us to accept that natural variation is large as the warming trend ... then all the warming trend can be explanined by natural variation and there is absolutely no reason to believe we are not living at a time of totally normal and natural climate variation.
So by this the authors argue that surface temperatures in climate models should be revised downward by the use of a blending method?
They could almost be accused of creeping ever closer to admitting that you cannot physically represent the temperature of the earth with a single number.
MikeHaseler, you are clearly a person with common sense. Global Warming experts are not.
Ref BH Update, is the use of the word 'blended' simply a euphemism for 'conveniently selected mish mash'?
If so, 'blending' makes perfect sense, as it all seems to look like junk science, but with extra fudge, to mask the taste of flannel.
If the modelled temperatures do not agree with actual/factual data, then obviously the actual/factual data MUST BE WRONG.
Are all you temperature readers cross-eyed or what? Lift your game - you navvies.
golf charlie : "MikeHaseler, you are clearly a person with common sense."
Not really. I just happen by accident to get involved at an early stage with wind and knew many of the people involved in Scotland & even the UK and as a result I never had any rose tinted glasses about the pure business greed that drove most of them.
Also because I happened to get involved in wind, I thought I should join the Greens and ... well "gullible" is being kind because most were clueless.
And finally I made the mistake of trying to edit wikipedia - it was just a link to "peak oil" on the Global warming page because I genuinely thought anyone interested in Global warming would also be interested in peak oil. That's how I came across Connolley and the rest of the eco-activist academics at the core of this scam ... and the rest is history.
If the temperatures from the models can't be directly compared to a certain set of observations, then what have the creators of the models been comparing their results to and why have many "scientists" been producing graphs which compare the model outputs to observations? Or why have the model results been in unusable units instead of producing usable results?
"blended observational data"
A bit like cheap Scotch, then - something you give to people you don't like.
Here are some thoughts on the paper.
(1) Why a 1975 start date? The model-obs discrepancy begins in the late 90s. From 1975 to 1998 you're still in the training interval where the models and observations have to agree by construction. In any case, doesn't matter for Figure 4, which starts in 1880 and summarizes the findings.
(2) This study doesn't address why the models and observations are so far apart in satellite and weather balloon records where SST isn't an issue. The LT and MT discrepancies are statistically significant.
(3) The post-98 discrepancy has models running hot compared to observations. So the obvious question is, do the observations need to come up or the models come down? Their final graph shows the model runs come down when they use the air/sea blend, but not by enough to address the discrepancy in any meaningful way.
(4) The big change in the discrepancy (Fig 4b) comes from using updated forcing data from Schmidt, which seems to indicate the models predict much less warming than before. But this is unrelated to the topic of the paper.
(5) The whole rationale for using SST records in the surface AT (SAT) calculation is the assumption that they are good proxies for nearby marine air temperature (MAT). The observational evidence from the tropics is that SST overstates nearby MAT trends. This paper argues that in the models, SST understates nearby MAT trends. The paper's conclusions depend on the premise that the model-generated SST-MAT discrepancy is a valid feature of the real world. They should show the spatial pattern of SST-MAT trend discrepancies in models versus that in observations. I'll bet they don't match at all, at least where they can be measured.
(6) The HadNMAT2 data set shows the same hiatus as all the other data sets. But it is somewhat sparse. This paper says a lot of MAT warming is out there, but it's not being picked up in the SST data. So we are asked to assume that the MAT warming is hiding in areas where there are no MAT measurements, and if it doesn't show up in SST data either then we should assume SST trends underestimate MAT trends. OK, but someone better tell Karl et al., because their recent hiatus-buster paper assumed that the HadNMAT2 data underestimated the SST trend.
(7) I assume the model-obs discrepancy would show up in a land-only comparison. It would have been helpful if the Cowtan paper had addressed this.
MikeHaseler, I am just a country bumpkin at heart really. I couldn't help noticing that mother nature hadn't noticed the change in climate conditions, that climate scientists claimed they had. Mother Nature has always been very set in her ways, and slow to change, unlike Green propaganda of course, which gets worse with every season that passes without incident.
Best thing about Cowtan is that he comes with a baggage, namely the pause busting article of 2013. The one where as if by magic the north pole got infilled just enough to bring about the. 12C/decade expected by models.
Rahmstorf eulogized that work, a single article which made the "debate" about the pause "completely baseless"
http://www.realclimate.org/index.php/archives/2013/11/global-warming-since-1997-underestimated-by-half/
Nice to see Cowtan work at taxpayers' expenses on something completely baseless. I wonder if better scientists would retract the old paper as it's by their admission 62% wrong. Or more,
michael hart
"They could almost be accused of creeping ever closer to admitting that you cannot physically represent the temperature of the earth with a single number."
Anyone who has had the most meagre education In the Statistics of Regionalised Variables is completely aware that sampled distributions that come from domains with distinctive distributions of those variable from other domains knows that blending means, coefficients of variation and Kriging coefficients of different domains generates statistically invalid and totally useless values.
The oceans, seas, ice caps and atmosphere are composed of a large number of distinctive , and often ephemeral, domains each with its own characteristic suite of variable, and often time dependant values such as temperature, humidity, pH etc. Mathematically "blending" parameters such as temperature and postulating that the "average" has any meaning is at the very least both geo statistically and scientifically meaningless.
Just to show how loony such averages are just imagine a 24 hour period in a specific location during which a warm , moist air mass of Azorean origin passes slowly across the station location over a 22 hour period with characteristic temperature and humidity of such an air mass ( = domain). Then a cold front passes rapidly through and the wind swings to the north or north east bringing down a cold, dry continental Arctic airmass onto the station. The average temperature for the 24 hour period will be something like 22 hour of say 17º¸and 2 hours of say 8ºC giving a time weighted average temperature of 16.25º¸ while the average of the Max and Min that goes into the tempeature database will be 12.5ºC. And these peoplethink they can tell whatthe average temperature is to withing fractions of one degree and that their numbers have some self standing validity - DELUSIONS.
Then remember that 70 % of the earths surface is ocean and another 10 % is polar ice cap neither of which are extensively sampled, and that different air masse are swirling around the globe, as are different ocean water masses and then try and persuade me that we have the remotest idea what the "average" temperature is OR THAT IT HAS ANY MEANING AT ALL.
Same Rahmstorf was even opining a tad later that the slowdown was becoming an acceleration, again thanks to Cowtan
http://www.realclimate.org/index.php/archives/2013/12/the-global-temperature-jigsaw/comment-page-2/?wpmp_switcher=mobile&wpmp_tp=3
Anyone who has had the most meagre education In the Statistics of Regionalised Variables is completely aware that sampled distributions that come from domains with distinctive distributions of those variable from other domains knows that blending means, coefficients of variation and Kriging coefficients of different domains generates statistically invalid and totally useless values.
Not to mention that there are an infinity of ways of defining a "global average temperature", all of them physically meaningless, and none of them having any reason to be preferred over the others.
Ross McKitrick, thank you for your technical appraisal. It seems that experts still can't find the missing heat, whilst we all pay 'protection money' to shield us from the damage it may do to us.
Al Capone would have marvelled at the wonders of modern science, and how computer models can replace guns as weapons of mass extortion.
If a subject has the word "science" in its title, that's a good indication that it is not science.
And...
If a paper has the word "robust" in its title, that's a good indication that it is flaky.
Martin A 6:28, yes agreed, but "blending? air and sea temperatures???
In the middle of an arctic winter, air temperatures may be -30c. Drill a hole through the ice, and ultimately sea water of +0.1c will be found. This type of science requires proper blending, with a liquidiser. It may then be made more "robust", by throwing it in a bin with liquid nitrogen.
IPCC peer approved science, and FIFA Fair Play Awards have a lot in common.
So the science is still settled is it? The debate is still over as well? I am a little perplexed as to why they are still arguing amongst themselves as the debate is over. The missing heat ( except there is no missing heat) is in the oceans where it cannot do any harm , except that it is causing unprecedented weather except that none of it is unprecedented.
The ice is melting and will be gone by two years ago except that it isn't gone. In fact there is more sea ice than ever since we started taking an interest. The Pacific Islands are going to disappear except that they are getting bigger. The Maldives will eventually sink under the weight of concrete runways, not from 3mm a year sea level rise. The Dutch have not abandoned the Netherlands to the sea. The richest people in the world , Gore, Suzuki, Branson, etc have not changed their lifestyles one jot. The clamouring clowns, De Caprio, Bono, Stink, Geldof, Viv Westwood, etc have not given up anything to save the world. I am a little confused as to why I have to freeze to death this winter to save the Planet when none of these fools make any effort.
So until at least one of the enlightened ones actually starts playing the game for real they can count me out. Oh and Mr Cowtan......Ask the Chinese what they think of your science. I think you'll find they don't give a Shanghai sh.......... what the latest cobbled together crap from the UK is all about.
Geospeculator: Thank you for your fisk of what is laughingly called the Global Average Temperature (GAT). In the past, whenever I have written about this I tend to call it, "GAT (whatever that is)": The 'whatever that is' is what you wrote. Thanks.
Ivor Ward, I think the Chinese would be very interested in climate science, if they didn't have loads of other more useful things to do.
They saved the Panda after all, once they realised from WWF publicity what a brilliant commercial asset they were.
The premise for this paper does seem a remarkable commentary on climate research. Apparently, only now is serious thought being given to the appropriate way to evaluate GCM output against observed data! Is this not a little late in the day? Or were the models never intended for empirical evaluation?
" ... And once you understand that these academics own predictions force us to accept that natural variation is large as the warming trend ... then all the warming trend can be explained by natural variation and there is absolutely no reason to believe we are not living at a time of totally normal and natural climate variation." ~ MikeHaseler
Agreed. And the more we see that nothing out of the ordinary is going on, the more we can see that those of us who have come to think that CO2 does not do diddly (CO2 climate sensitivity of zero) are not so far off the mark as so many may think. ~ Mark
basicstats, as someone who admits to have been fooled by Mann and his Holy Hockey Stick, my opinion is that at the time, the correlation of a rise in CO2, and a rise in temperature did seem linked, and this matched the ideology of those who saw it as the developed worlds responsibility to pay for the undeveloped. This also tied in with the assumption that fossil fuels were about to run out.
Since then, CO2 has continued to rise, temperatures have not. The developed world is prevented from aiding other countries with fossil fuels. Exploitable fossil fuels keep increasing in reserve, as more technology has been deveolped.
Climate scientists keep resorting to more elaborate reasons why they are still right, as more non scientists are able to point at simple things which have not happened as predicted by expert climate scientists.
So it is all plain sailing ahead for climate scientists, according to their weather forecasts.
GCMs depend on projections of forcings. They also assimilate past observations for comparison purposes.
If the forcings and observations that are used are not the same as those that the GCMs are being compared to then the comparisons with the models are not valid.
Errors in forcings used in the CIMP5 series compared to what actually happened account for about 40% of the difference
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20150000726.pdf
Cowtran et al show that mismatches of the things being compared accounts for about 35% of the mismatch.
In recent years the prevalence of the LaNina phase account for the rest.
Eli, thank you for explaining that Cowtan highlights how much is wrong about previous assumptions in climate science.
I prefer Ross McKitrick's assessment, as he does not start with the assumption that Cowtan is right, even now.
But it is encouraging that climate science has commenced rethinking previous work, hopefully it will not stop there
Ross seems to have great experience with making wrong assumptions.
In recent years the prevalence of the LaNina phase account for the rest.
Well, yes. The lack of warming is responsible for the lack of warming.
What the models failed to predict was the prevalence of La Nina. We were told, categorically, that there would be accelerating warming instead.
If the forcings and observations that are used are not the same as those that the GCMs are being compared to then the comparisons with the models are not valid<\i>
Does this make all those nice little IPCC reports kind of "not valid"?
I think you are understating the significance of the study. It is not clear if they are using Cowtan and Way adjusted Hadcrut, which might reduce the discrepancy further.
Also, the effect was to cool down the models. It introduces the possibility of using the NOAA's pause busting adjustments to the same methodology. So now you can bring the observations up and the models down.
Did they report what the apples to apples new projections are for the models? Should we subtract 38% from 3C, and say 1.86C? Or is it 62% of 1.5C + 1.5C(observed) = 2.43C?
This paper is just another example of the culture of corruption in the climate concerned community.
Hide The Decline:
https://www.youtube.com/watch?v=WMqc7PCJ-nc
The upshot of their paper is twofold:
1. When comparing model output to temperature data, one should only compare the model output with satellite temperature data since the model output is a projection of air temperature only (not SST and land based air temperature as favoured by the many thermometer data sets) and so too is the satellite temperature measurements (although satellites measure air temperature at height).
2. The models have been incorrectly tuned; they should have been tuned simply to air temperature data not some homogenisation of SST and air temperature.
Whatever, the fact remains that there is a significant discrepancy between model projections and real world observation and that that gap is widening as the years go by.
Whatever the explanation be for the gap, it simply confirms that mode projections are worthless since they do not mirror well what is happening in real world.
Whichever way you look at this paper it doesn't speak well for the climate science community. A chemist from the University of York has discovered that:
1. The cream of the climate science modellers producing models for the IPCC hadn't noticed that the models were being compared to a dataset that wasn't represented in the models.
2. Hundreds, possibly thousands, of peer reviewers hadn't noticed that the models were being compared to a dataset that wasn't represented in the models
3. The training data is complete and utter bullshit because they managed to get the number of ham sandwiches identical to the real number of cheese toasties.
4 Not only have the modellers not noticed their egregious error, but thousands, perhaps tens of thousands, of climate scientists didn't notice it.
5. The Met Office and the CRU whose data was used for the comparison, and who themselves have modellers whose work is used by the IPCC didn't notice it
I say, "Bravo!" to this chemist who in one single paper, co-authored with some quislings from the climate science community, has finally pricked the bubble of omniscience the climate scientists claimed for themselves (along with their fake Nobel Laureates).
Am I over the top? Or is it credible to anyone else that thousands of scientists have overlooked this most basic of errors for in excess of 20 years?
If Eli's new assertions are correct; ie that 35 to 40% of the problem is due to climate scientist selecting pessimistic model forcings and the remaining error is due to climate scientists failing to appreciate the natural positive phase of the pdo/enso cycle then the McKitrick and Michaels paper lampooned in the link he pointed to was evidently proven correct, despite the inconsequential programming error (certainly far less of an error than upside-down proxies or blatantly-biased data-mining or arguing that larger error bars somehow make the models better rather than worse, etc, etc).
We should therefore expect Eli the scientist to be more humble after tacitly admitting to being wrong all this time while skeptics were telling him about the obvious unscientific circular reasoning and confirmation bias involved in making these input errors about forcings and natural cycles. Alas the hypocrisy and sanctimoniousness of his dominant activist persona allows him and his ilk to imagine themselves still morally correct whilst factually incorrect almost 100% of the time; ie worse than random rabbits.
Well at least it is a welcome change for these pause deniers to finally recognise the discrepancy between models and reality - albeit later than everyone else. However sane people still believe that models should be adjusted to match obs rather than the other way around and we've been saying this for nigh on 15 years. And indeed we do have good satellite obs for the last 35 years that activist-scientists still like to avoid mentioning because it shows them to be even more wrong. Maybe they should start listening to skeptics more and stop being guided so much by facile & failed neo-Luddite ideologies.
Josh: "In recent years the prevalence of the LaNina phase account for the rest"
Nope:
http://www.nature.com/ngeo/journal/v7/n3/fig_tab/ngeo2098_F1.html
"Ross seems to have great experience with making wrong assumptions."
Indeed, he made a mistake in a paper written 15 years ago. That's not a bad track record for a guy whose published 36 papers, 30 of them since 2000.
At least he doesn't refer to himself as "Wossy Rossy".
Now if Mr. Wabbett would like to explain to us why tens of thousands of climate scientists failed to notice that the models weren't using the right data set for 25 years I'm all ears. (Pun intended)
If the discrepancy between models and data needs to be eliminated, the rate of warming in the models needs to come down.
We knew that.