A global temperature conundrum: Cooling or warming climate?
From the University of Wisconsin-Madison
MADISON, Wis. — When the Intergovernmental Panel on Climate Change recently requested a figure for its annual report, to show global temperature trends over the last 10,000 years, the University of Wisconsin-Madison’s Zhengyu Liu knew that was going to be a problem.
“We have been building models and there are now robust contradictions,” says Liu, a professor in the UW-Madison Center for Climatic Research. “Data from observation says global cooling. The physical model says it has to be warming.”
Writing in the journal Proceedings of the National Academy of Sciences today, Liu and colleagues from Rutgers University, the National Center for Atmospheric Research, the Alfred Wegener Institute for Polar and Marine Research, the University of Hawaii, the University of Reading, the Chinese Academy of Sciences, and the University of Albany describe a consistent global warming trend over the course of the Holocene, our current geological epoch, counter to a study published last year that described a period of global cooling before human influence.
The scientists call this problem the Holocene temperature conundrum. It has important implications for understanding climate change and evaluating climate models, as well as for the benchmarks used to create climate models for the future. It does not, the authors emphasize, change the evidence of human impact on global climate beginning in the 20th century.
“The question is, ‘Who is right?'” says Liu. “Or, maybe none of us is completely right. It could be partly a data problem, since some of the data in last year’s study contradicts itself. It could partly be a model problem because of some missing physical mechanisms.”
Over the last 10,000 years, Liu says, we know atmospheric carbon dioxide rose by 20 parts per million before the 20th century, and the massive ice sheet of the Last Glacial Maximum has been retreating. These physical changes suggest that, globally, the annual mean global temperature should have continued to warm, even as regions of the world experienced cooling, such as during the Little Ice Age in Europe between the 16th and 19th centuries.
The three models Liu and colleagues generated took two years to complete. They ran simulations of climate influences that spanned from the intensity of sunlight on Earth to global greenhouse gases, ice sheet cover and meltwater changes. Each shows global warming over the last 10,000 years.
Yet, the bio- and geo-thermometers used last year in a study in the journal Science suggest a period of global cooling beginning about 7,000 years ago and continuing until humans began to leave a mark, the so-called “hockey stick” on the current climate model graph, which reflects a profound global warming trend.
In that study, the authors looked at data collected by other scientists from ice core samples, phytoplankton sediments and more at 73 sites around the world. The data they gathered sometimes conflicted, particularly in the Northern Hemisphere.
Because interpretation of these proxies is complicated, Liu and colleagues believe they may not adequately address the bigger picture. For instance, biological samples taken from a core deposited in the summer may be different from samples at the exact same site had they been taken from a winter sediment. It’s a limitation the authors of last year’s study recognize.
“In the Northern Atlantic, there is cooling and warming data the (climate change) community hasn’t been able to figure out,” says Liu.
With their current knowledge, Liu and colleagues don’t believe any physical forces over the last 10,000 years could have been strong enough to overwhelm the warming indicated by the increase in global greenhouse gases and the melting ice sheet, nor do the physical models in the study show that it’s possible.
“The fundamental laws of physics say that as the temperature goes up, it has to get warmer,” Liu says.
Caveats in the latest study include a lack of influence from volcanic activity in the models, which could lead to cooling — though the authors point out there is no evidence to suggest significant volcanic activity during the Holocene — and no dust or vegetation contributions, which could also cause cooling.
Liu says climate scientists plan to meet this fall to discuss the conundrum.
“Both communities have to look back critically and see what is missing,” he says. “I think it is a puzzle.”
The study was supported by grants from the (U.S.) National Science Foundation, the Chinese National Science Foundation, the U.S. Department of Energy, and the Chinese Ministry of Science and Technology.
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“Data from observation says global cooling. The physical model says it has to be warming.”
Obviously , it must be warming . All else is heresy of the first , second and third order , besides , big oil has been known to use data which immediately makes data untrustworthy and guilty of apostasy by association
If the models fail to mirror reality the MODEL is wrong. BASIC science. Learn or fail!!
I’m just glad that – at a time we need supercomputers to save us – we have supercomputers!
What I forgot to say in my earlier comment: THERE SIMPLY IS NOT A SINGLE CLIMATE MODEL worth the name, in existence anywhere, as I tried to illustrate in
http://cleanenergypundit.blogspot.co.uk/2013/01/snippets-questions-2-climate-models.html
http://cleanenergypundit.blogspot.co.uk/2013/02/snippets-questions-2-comments.html
http://cleanenergypundit.blogspot.co.uk/2013/05/snippets-questions-2-some-answers-re.html
or in
http://cleanenergypundit.blogspot.co.uk/2013/09/blog-post.html
or
http://cleanenergypundit.blogspot.co.uk/2014/06/eating-sun-fourth-estatelondon-2009.html
That said, I am now rueing that I allowed myself to fall into the trap I should have avoided in line with an earlier comment I made elsewhere:
“I am getting bored. The globe can be getting warmer or colder, but the idea that the human contribution from burning carbon fuels has anything to do with it is not only IMHO the biggest political and intellectual fraud ever – but so says the IPCC itself: http://cleanenergypundit.blogspot.com/2011/10/west-is-facing-new-severe-recession.html. The ongoing discussion pro and con is becoming akin to the scholastic argument as to how many angels can dance on the head of a needle. Which is, of course, exactly what is intended to achieve worldwide disorientation away from the actual IPCC aims of monetary and energy policies – and bringing a whole, if not all, of science into disrepute”.
And if you want to see how big that trap is, try those two TYGER reads, as in http://cleanenergypundit.blogspot.co.uk/2014/06/tyger-spoors.html and
http://cleanenergypundit.blogspot.co.uk/2014/07/tyger-lair-from-edenhofer-interview-1.html
Warning: you read these at your own risk!
Now, after five years of my bloggery I put together a BLOG LOG http://cleanenergypundit.blogspot.co.uk/2014/08/blog-post.html
of all my postings, after which I consider that my first blog is still as valid as ever
http://cleanenergypundit.blogspot.co.uk/2009/08/clean-energy-primer-quousque-tandem.html
Many things I learned since during my meanderings, above all the recipe book for the way ahead, by the incomparable Hermann Scheer:
http://cleanenergypundit.blogspot.co.uk/2012/09/at-risk-of-boring-you-i-must-quote.html
What is wrong with these idiots ? They ALWAYS start with the same effing flawed assumption, that CO2 is a significant driver of global temperature. And then when they can’t square the circle they say there must be someong wrong with the data, or there is a conunudrum, or we haven’t worked it out yet.
What is wrong with them? Why can’t they just say maybe CO2 is irrelevant.
Thanks, Fred C; lucid.
=============
We have to disappear the Holocene Optimum,
that that young fool Marcott exposed to the world.
====================
Well, the answer to their “conundrum” is obvious; the climate is confused, due to man’s sudden and massive increase of CO2. Climate Confusion© can create an appearance of cooling when in fact it is warming. The Climate Confusion© factor simply needs to be put into the GCM’s, and presto, problem solved.
Jennifer Marohasy ( http://jennifermarohasy.com/ ) insightfully points out that bad paradigms do not simply fade away. They last until replaced with something better. The paradigm behind the climate catastrophe madness of the past ~25 years is an example of this idea. CO2 obsession has motivated many millions of words to be written. Laws passed. Conferences held. Academic and political careers. Funding for NGOs. Industrial investments. Treaties. Endless news reports. Personal arguments. Etc. etc. etc. That is what a a paradigm does. CO2 obsession reached a critical mass in the public space years ago. Claiming CO2 has no influence is not going to work for many reasons.
This sort of report offers a new paradigm. It shows that there is a context for what CO2 can do.Let’s see if it holds up.
I wonder if one was to create a word list, then ‘sort’ the model source code, de-duplicate it etc and end up with a list of functions, could one say that every function in this list was
a) mapped physical reality (based on tested physics)
b) that the function had been fully tested
Looking at the results of models published so far, the answers appear to be No and No.
When the world of climate modelers crashes, please keep them away from aircraft simulators…
Mooloo spouted: “Says they used Marcott’s data, previously ripped to shreds by McIntyre & other. / He never attacked the data. Nor even the real conclusion of the actual paper. What was ridiculed was the comparison of non-proxy to proxy measurements, mostly made in press releases and articles. / Marcott’s actual paper supports long-term cooling quite strongly.”
DUH alert: Since Marcott raw data failed to tick up in the modern era, obviously to any school child is the fact that his proxies are not reflecting temperature at all. Nor did his fake hockey stuck use any non-proxy data, but relied for the blade instead upon sudden spurious data drop-off at the end due to bizarre proxy re-dating. That it was then described to NY Times reporter Revkin as a “super hockey stick” with a swoosh gesture, over video chat, removes all doubt that Enron level fraud was at work. Citing Marcott except as an example of brazen in-your-face pure power play fraud enables the “scientific” “debate” to continue to make a mockery of reason and of morality too.
-=NikFromNYC=-, Ph.D. in carbon chemistry (Columbia/Harvard)
The models are just too primitive. Do they have clouds in the models? Do they account correctly and for all cloud forming phenomena? Do they do cloud-radiation physics correctly? Do they take into account solar spectrum shift towards UV at time of high activity? Do they take Svensmark’s Effect into account? Do they account for MHD heating in the ionosphere and in the polar regions? And then there’s the whole gamut of biosphere interactions and influences, from changes in albedo to changes in air and water chemistry.
I see they are still trying to push the claim that the Little Ice Age was only in Europe.
Stephen Richards, thanks for pointing out just how deep the rabbit hole goes with “physical” climate models. Next I want to hear their physical musicians and physical poets. Oh, I guess they already are physical, as are supercomputers and perhaps likely our every thought too. The joke is on them though since climate models rely much more on parameters than on physics, for their wiggle matching and future magic spells.
Stephen Richards says:August 12, 2014 at 1:38 am
Isn’t “Physical Model” a strange phrase ? Why are they using the word “physical” ?
That seemed odd to me as well, perhaps hoping to lend credence to their silicon model, which isn’t working.
Maybe now we can rename it to the “Selfie Science”. Selfie Science – to apply one’s own catastrophic propaganda agenda that warmist’s thought processes abide by, while promoting the fraudulant 97% facade.
Are they going to ignore Otzi the hunter found under retreating ice and large forests that existed 4-5000 years ago where glaciers cover in Switzerland today? Look, before the meeting, how about: it warmed like hell out of the glacial max, grew deep dark forests even high up in the Alps, cooled again burying forests under 100s of metres of ice and entombing a fallen hunter, then, with warming and cooling spells oscillating, remelted 5000yr old ice showing us the evidence of a much warmer world – not yet fully uncovered. We know Hannibal’s elephants didn’t have snow shoes and crampons. We know George Washington’s men rolled cannons across the ice from Manhattan to New Jersey under the noses of British troops and people walked across the ice of New York Harbor to Staten Island in the early 19thC….Proxies are only equivocal if you insist it either warmed or cooled. It did both and the proxies are screaming it at you linear loons.
these people spent how long in education,then how many years as “climate scientists” ? what a complete and utter waste of a life.
“Physical Model?” I thought that was what aircraft designers stuffed into a wind tunnel to see if the design would, perhaps, fly.
It’s actually quite revealing, that the computer model is seen as some kind of physical reality, while the temperature “data” is somehow a malleable construct that we should be able to force into conformance with that model.
We’re not cooling, we’re just warming in another direction.
Mike
(apologies to Major General OP Smith)
In other news, the University of Wisconsin-Madison was only ranked number 8 in the Princeton Review’s 2014 ranking of top Party Schools in the USA while being ranked number 2 in Playboy’s 2014 ranking. UW-M is a perennial top ten finalist and previously ranked as high as number 1 by Playboy in 2006 and 2009.
http://en.wikipedia.org/wiki/Party_school
UW-M promises to relentlessly strive to re-attain its former illustrious standards and high ranking; this is demonstrated by the University’s professor’s willingness to contort like a pretzel for the good of the global warming cause.
D. Cohen says:
August 11, 2014 at 7:14 pm
If you don’t think it was a lot warmer 5000 or so years ago, you might try reading the article in the recent National Geographic about the recently discovered ruins of a rich maritime civilization based on the Orkney Islands north of Scotland (yes, those Orkney Islands, extremely cold and barely habitable today). Back then there seems to have been a prolific agricultural society lasting for about a thousand years or so and rich enough to support perhaps ten thousand or more people — a lot for megalithic Europe. No one had discovered these ruins before — even though they were right there underneath the surface — perhaps because it seemed “obvious” that no large megalithic civilization could exist so far north in such a rotten climate. Clearly it wasn’t such a rotten climate back then. When even the archaeologists are saying temperatures were much warmer during the holocene optimum, I think the debate is over!
You need to reread your history, the megalithic monuments have been known for a long time, the neolithic village of Skara Brae was uncovered in the 1850s for example and is a designated european heritage site. The henge structure at Stenness has been known for a long time (hard to miss) the locals used to use it in various rituals, Sir Walter Scott visited it in 1814.
“With their current knowledge, Liu and colleagues don’t believe any physical forces over the last 10,000 years could have been strong enough to overwhelm the warming indicated by the increase in global greenhouse gases and the melting ice sheet, nor do the physical models in the study show that it’s possible.”
–>warming indicated by the increase in global greenhouse gases and the melting ice sheet<–
The models are probably assuming far too high of a climate sensitivity to CO2, as well as neglecting other variables, e.g. clouds. It sounds like the study using proxy data from 72 locations treated the contradictory data which showed warming as outliers and were ignored, producing a supposed gradual cooling over the past 7,000 years in order to produce a hockey stick.
But, there is at least now empirical evidence that they are starting to get it, “Or, maybe none of us is completely right. It could be partly a data problem, since some of the data in last year’s study contradicts itself. It could partly be a model problem because of some missing physical mechanisms.”
Despite the crusade to discredit the "amazing coincidence" of correlation of solar activity and the relatively very minor climate perturbations during the Holocene, my money is on a light bulb moment occurring during solar cycle 25 when this "amazing coincidence" again takes place.
denniswingo says:
August 11, 2014 at 3:41 pm
That is correct. Volcanoes have no effect on climate, but can & do affect the weather for a year or two, making it colder at first, then warmer in general.
“Nature sides with the hidden flaw.” The hidden flaw in their models is that there is much the models fail to account for. Unfortunatel there is also something called the Dunning-Kruger Effect, which in instances like these means that the more you think you know about something the harder it will be to discover what you don’t know.