SNAP: 'Data says global cooling, physical model says it has to be warming'

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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kenw

““The fundamental laws of physics say that as the temperature goes up, it has to get warmer,” Liu says.
hmmmm…..

frozenohio

Stop the insanity!

So what happened to all that “settled science” I keep hearing about?

Daniel G.

The climate modellers (and pretty much everyone else) are uncertain of the causes of very low-frequency climate effects.

David S.

Maybe they could conduct a poll to determine the consensus?

Ooopsie!
Oh, by the way, Antarctic sea ice has been greater than +2x standard deviation above its established NSIDC daily averages for a couple of years now …
Been steadily increasing ever since 1996.

LT

When did the parameter aka as climate sensitivity become a fundamental law of physics

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.

So these guys still believe in Mann-made hockey sticks, eh?

cnxtim

97% – nn% = ?

Latitude

so they eliminated everything “known”.. it had to be CO2
…now we have unprecedented never before global cooling

Yea, so the volcanos in 1253, 1783, and 1816 meant nothing to climate….

Allen63

One thinks as ice melts, it cools the surroundings. The heat goes into making water out of ice (“Heat of Fusion”).
So, the idea that “glacier retreat” signals increasing temperature seems wrong. We may have reached a “maximum” that caused ice to melt — and are being pulled down from that maximum by the melting ice. Of course, I may be missing something.

The doi link is broken for the paper, but the supplemental info is online:
http://www.pnas.org/content/suppl/2014/08/08/1407229111.DCSupplemental/pnas.201407229SI.pdf
Says they used Marcott’s data, previously ripped to shreds by McIntyre & others

Curious George

“The fundamental laws of physics say that as the temperature goes up, it has to get warmer,” Liu says.
Grrrh!

Claude Harvey

“The fundamental laws of physics say that as the temperature goes up, it has to get warmer,” Liu says.”
What? This is better than the “freezing water causes ice” government report we were recently treated in ref. to the Great Lakes.

denniswingo says:
August 11, 2014 at 3:41 pm
Yea, so the volcanos in 1253, 1783, and 1816 meant nothing to climate….
————————————————————————————————————————–
In terms of a 10k year trend, no hey probably don’t. Just blips along the way.
Besides, surely the real interest in this is that (gentle) challenges to (some aspects of) the “settled science” are not only being invesigated but also being reported. Hard to imagine that happening even 5 years ago.
Big avalanches start with little snowballs and there’ve been a few snowballs thrown recently.

tty

“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.”
Pure bullshit. Annual layers are extremely rare and only exist in areas with oxygen-free bottom water (which doesn’t exist in the North Atlantic). Otherwise bottom living animals churn up the sediments (“bioturbation”), so no matter how finely you slice a core you will be sampling a mixture of sediments deposited over a longish period.

Don B

When Marcott did his PhD thesis, before he apparently felt compelled to join the IPCC crowd, his proxies showed global cooling for several thousand years.
http://rogerpielkejr.blogspot.com/2013/03/fixing-marcott-mess-in-climate-science.html

redc1c4

i don’t understand how everyone missed the obvious solution…
we just need to refine & adjust the data until it fits the model: problem solved.
you can mail me my Nobel Prize

Jim Clarke

“It does not, the authors emphasize, change the evidence of human impact on global climate beginning in the 20th century.”
Yes, it does. Proclaiming, with emphasis, to the contrary, does not change the fact that this is just more evidence that their guesstimate of human induced warming is wrong. Talk about denial. ..

tty

Actually everybody who has the slightest interest in Quaternary Geology knows that it is normal for the beginning of interglacials to be warmest and for the temperatures to then gradually decline, just as they have done in the current interglacial. This is the way things are, and it’s about time that ‘climate scientists’ start taking note of the real world, even when it doesn’t fit their models.

Jim Clarke says:
August 11, 2014 at 3:57 pm
Proclaiming, with emphasis, to the contrary, does not change the fact that this is just more evidence that their guesstimate of human induced warming is wrong. Talk about denial.
——————————————————————————————————————–
Denial, or “pointing out a problem while still gettiing into print”?

tty

“So, the idea that “glacier retreat” signals increasing temperature seems wrong. We may have reached a “maximum” that caused ice to melt — and are being pulled down from that maximum by the melting ice. Of course, I may be missing something.”
You certainly are. The glaciers have been expanding for the last 7,000 years or so, which is just what you would expect in a cooling world.

Jared

Take an ice cube and stick it in 80 F temps, then reduce the temp to 75 F. I assume even though the temperature decreased that the ice cube kept melting. I will wait for Nye/Gore/Stokes to confirm.

joelobryan

The Tautologist said: “The fundamental laws of physics say that as the temperature goes up, it has to get warmer,” Liu says.

Don B says: August 11, 2014 at 3:52 pm
“When Marcott did his PhD thesis, before he apparently felt compelled to join the IPCC crowd, his proxies showed global cooling for several thousand years.”

It still does. That’s the result they are quoting.

kim

Doesn’t seem to understand that Marcott smoothed any previous ‘profound global warming trend’. Honestly, does he think slipping that in is going to add to his credibility?
Marcott’s downward trend through the Holocene has not been debunked.
Again, it’s models vs proxies.
Read his stuff again; the credulity of some of those clowns.
==================

Or as Alexius Meinong reminds us:
“Truth is a purely human construct, but facts are eternal”,
best read together with
““The Creation speaketh an universal language, independently of human speech or human language, multiplied and various as they may be. It is an ever-existing original, which every man can read. It cannot be forged; it cannot be counterfeited; it cannot be lost; it cannot be altered; it cannot be suppressed. It does not depend upon the will of man whether it shall be published or not; it publishes itself from one end of the earth to the other.”
Thomas Payne THE AGE OF REASON

rgbatduke

This is only a small part of the problem. The Holocene is, after all, an interglacial in a protracted ice age. Trying to explain the Holocene out of context of the last five million years:
http://commons.wikimedia.org/wiki/File:Five_Myr_Climate_Change.png
which is all impossible to explain within existing climate models, or worse, back 65 million years:
http://commons.wikimedia.org/wiki/File:65_Myr_Climate_Change.png
or still worse, 542 million years:
http://commons.wikimedia.org/wiki/File:Phanerozoic_Climate_Change.png
illustrates the real difficulties facing us. We are in a geological era of major glaciation the likes of which the world has only seen once in the last half-billion years, experiencing the coldest local (short term) average temperatures in 450 million years. The last time temperatures were this low, atmospheric CO_2 was roughly 4000-5000 ppm — over ten times what it is today. Well over 95% of the last half-billion years has been spent with temperatures higher than they have been on average (including interglacials) in the Pleistocene ice age. At least, if we can trust the radiometric proxies and their interpretation.
We cannot explain or predict the climate dynamics on any of the timescales from the Holocene only:
http://commons.wikimedia.org/wiki/File:Holocene_Temperature_Variations.png
right up to the present, where at the moment we thought we could explain the one 15 year burst of warming in the latter 20th century, at least, as the result of CO_2 increases, only to have it stop for the next 15 years while CO_2 continued to increase. The paper above is merely openly acknowledging a problem that we’ve been discussing on WUWT threads for many years now, a problem that is, after all, obvious. We cannot predict, or understand, the shortest time dynamics of the climate, the interval directly following the reference period used to normalize the models, let alone the last 400 years (LIA and post-LIA warming), the last 1000 years (MWP warming followed by LIA cooling followed by modern warm period warming that continues today, all part of the general cooling trend that followed the Holocene Optimum that we cannot explain or predict or model any more than we can explain why the Wisconsin glaciation ended, the Younger Dryas returned to glaciation for 1000 or so years, and then the world warmed right up to the Holocene optimum. We can do no more than guess that orbital dynamics and oceanic mixing patterns or global galactic dynamics and solar dynamics (basically nothing but words at this point lacking more than unexplained data and explanatory possibility devoid of direct evidence) have something to do with it, but only at the expense of acknowledging that these effects are, or can be, an order of magnitude stronger than the strongest possible greenhouse effect modulation because at the nadir of the Wisconsin CO_2 was down to 180 ppm, making one wonder how glaciation could ever have ended with CO_2 less than half its current value, if it is responsible for the bulk of the temperature increase since then.
However, this paper is still quite welcome. Sooner or later, climate scientists are going to realize the limits of their models, and in the process they may learn some things that are quite valuable.
Now, if only they’d stop mixing high frequency sampled data with low frequency sampled data and asserting that the modern warming is “unprecedented”:

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.

Note well how this quote from the top article leaves one with the dual impression that humans were responsible for “the hockey stick”, neglecting the facts that:
a) The hockey stick has long since been discredited. Yes Virginia, there really was both a MWP and a LIA (the coldest stretch of the entire Holocene), so there was no “stick”.
b) That humans began to “leave their mark” on the climate at the end of the LIA or Dalton minimum, when most climate scientists agree that CO_2 forcing was more or less irrelevant to the warming that took place before 1950, when atmospheric CO_2 was supposedly (still) only 300 ppm, within a hair of its presumed but arguable longer term (Holocene?) average of 280 ppm. The “human mark” is thus restricted to a single burst of warming from roughly 1983 to 1998 (plus a few years either way if you like, I’m not trying to cherry pick dates, only to point out that there was actual neutral-to-cooling temperatures from roughly 1940 to maybe 1980, then a bounce that started a warming trend up to the 1997-1998 super El Nino bounce that ended it. How, exactly, did humans cause the 1997-1997 super El Nino?
c) The almost identical pattern of warming that held from maybe 1920 to around 1940. CO_2 did not cause this warming, or the great Dust Bowl, unless my notion of entropy and causality is badly confused, that causes must precede effects. So perhaps this is part of the “human mark” but I defy anyone to illustrate this with anything like a defensible argument.
d) This latter data showing two bursts of sudden warming is high frequency thermometric data, sampling a direct measure of temperature, well distributed globally every day — and is still only accurate to 0.15C now (HADCRUT4). They are asserting a “profound global trend” on the basis of this thermometric data compare to what? The linked graph of the Holocene temperatures above, for example, openly acknowledges that the granularity of the data cannot resolve fluctuations of shorter duration than 300 years. Does the paper/top article above do better? I very much doubt it. It is just once again comparing 300 year smoothed apples to daily-sampled oranges, attributing all of the variation of the latter to humans in spite of the fact that the models themselves would have to contain an implicit time machine to attribute more than the warming that occurred in only 20 of the last 70 years — around 0.5 C total and almost the equal of the non-anthropogenic 0.4 C from the first half of the 20th century — to anthropogenic CO_2.
Arrgh! Why not just state up front that the models are broken, that this casts substantial doubt on the quantitative implementation of the CO_2-linked part of those models (since it CANNOT be made consistent with the observations of the entire Holocene, any more than it works for the last 150 years in figure 9.8a of AR5) and leave off the assertions that there is anything like a human-attributable hockey stick in the already misrepresented data. In order to assert warming at all for example, one has to say a few words about the error bars routinely omitted from HADCRUT4. Errors might be only 0.15C in 2014, but what about 1914? What about 1864? How much of the supposed warming is statistically uncertain in addition to being high frequency noise when compared to 300 year average warming presented in long term temperature graphs?
rgb

Theo Goodwin

“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.”
All the conditions have to be taken into account. When they are, all proxy records are found to be near worthless.

Andrew N

“Data from observation says global cooling. The physical model says it has to be warming”
“Data from observation says the sun is at the centre of the solar system. The Bible says it circles the Earth”
We’ll hold an inquisition to persecute the unbelievers…

catweazle666

More computer games…

joelobryan

From the last paragraph in the Introduction of Liu, Z, et al (PNAS, 2014):
Our analysis shows a robust warming trend in current climate models, opposite from
the cooling in the M13 reconstruction. This model-data discrepancy suggests potentially significant biases in both the reconstructions and current climate models, and calls for a major
reexamination of global climate evolution in the Holocene.
Note that last statement. Those Climate Scientists are beginning to feel their reputations are at serious risk with the coming cooldown and the IPCC’s model failures.

Michael Wassil

First they went after the LIA and MWP, now they’re going after the Holocene Optimum and everything in between. Can’t have that big hump of warming 10000 years ago warping the hockey schtick. Everything and anything that doesn’t support the ‘settled science’ has to disappear. I wonder when the Younger Dryas will go.

Shoshin

Real world data trumps models. Not sure why there is even a debate.
Unless of course, there is a much higher level of confidence in the output of a million line super-computer program that uses thousands of variables, each which may vary output radically, not to mention that the program produces different results on different computers vs. someone reading a temperature and writing it down.
Kind of an Anti-Occam’s Razor fixation I guess.

joelobryan

Actually on reading Liu et al a little closer, it seems they may also try to erase/reduce the Holocene Thermal Maximum to resolve the conundrum. But that would present a hornet’s nest of blowback from paleoclimate scientists who have spent their careers building that HTM from proxy data..

ROM

As it is climate models all the way down, that tortoise at the bottom must be getting pretty darn overloaded by now with all the climate modeler’s BS..
Gonna be quite mess for somebody to clean up when that tortoise finally collapses.

joelobryan

If anyone wants a pdf copy of Liu et al, email me at joel(dot)obryan(at)gmail(dot)com. and I’ll reply with the pdf.

john robertson

What these guys never got the memo?
Where actual measured values conflict with modelled “information” the models will rule.

Mooloo

Says they used Marcott’s data, previously ripped to shreds by McIntyre & others
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.

Christopher Hanley

‘… 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 …’
===============================
The first bit, the base, of the ‘hockey stick’ blade, represents the warming before ~1950 which was before human fossil fuel emissions were of any significance.

Jimbo

It’s unprecedented and we must act now!

“….robust contradictions,”

The robust observations are wrong, coz the models say so.

Athelstan.

Aw come on,
increase in Arctic sea ice – man made global warming
< in Arctic sea ice – mm global warming.
Bad freezing cold winter – mm global warming,
wet winter – mm global warming,
warm winter – mm global warming,
Black is white – mm global warming,
which way is north? – mm global warming,
Save the presidency – mm global warming,
Penn State U down the tubes – mm global warming.
mm global warming – it's time to have a tea party.

Jimbo

The three models Liu and colleagues generated took two years to complete.

Next please.

Pamela Gray

I wouldn’t go any broader than 1000 years to coincide with global over-turning circulation. The only thing that stores and releases more or less heat that more or less heats the atmosphere is the ocean. Smooth to that. Then look for why more or less heat went into the oceans to explain the rise and fall of atmospheric temperatures.

1sky1

It requires a tenured position to pretend that “The fundamental laws of physics say that as the temperature goes up, it has to get warmer” constitutes profound insight.

Ok, I am no Feynman. But do you need to be? When your models do not agree with the data, there is nothing wrong with the data! Your models suck!
The ignorance of climate scientists is mind boggling.

Mac the Knife

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.
It’s….. ALIVE!!!!!!
http://youtu.be/0VkrUG3OrPc

KevinK

Well…. In aerospace engineering when the models say; ‘That Pig Can’t Fly”, we always launch it anyway (and keep our fingers crossed that nobody will notice that its not really flying). I assure you good sir that contrary to your observations those tires are definitely not in contact with the ground…..
/sarc off
Cheers, Kevin

Having one of these disciples state that “the proxies are complicated” is a bit like having an IRS agent tell you that “the tax code is complicated”…really? You MADE THE FREAKIN TAX CODE, dude.
Here’s a thought…if the proxies are too complicated?…
Stop
Using
Proxies.
Jim