New interpretation of Antarctic ice cores

Bilder aus Bremerhaven

Alfred Wegener Institute Image via Wikipedia

Researchers at Alfred Wegener Institute expand prevailing theory on climate history

Climate researchers at the Alfred Wegener Institute for Polar and Marine Research in the Helmholtz Association (AWI) expand a prevalent theory regarding the development of ice ages. In the current issue of the journal Nature three physicists from AWI’s working group “Dynamics of the Palaeoclimate” present new calculations on the connection between natural insolation and long-term changes in global climate activity. Up to now the presumption was that temperature fluctuations in Antarctica, which have been reconstructed for the last million years on the basis of ice cores, were triggered by the global effect of climate changes in the northern hemisphere. The new study shows, however, that major portions of the temperature fluctuations can be explained equally well by local climate changes in the southern hemisphere.

The variations in the Earth’s orbit and the inclination of the Earth have given decisive impetus to the climate changes over the last million years. Serbian mathematician Milutin Milankovitch calculated their influence on the seasonal distribution of insolation back at the beginning of the 20th century and they have been a subject of debate as an astronomic theory of the ice ages since that time. Because land surfaces in particular react sensitively to changes in insolation, whereas the land masses on the Earth are unequally distributed, Milankovitch generally felt insolation changes in the northern hemisphere were of outstanding importance for climate change over long periods of time. His considerations became the prevailing working hypothesis in current climate research as numerous climate reconstructions based on ice cores, marine sediments and other climate archives appear to support it.

AWI scientists Thomas Laepple, Gerrit Lohmann and Martin Werner have analysed again the temperature reconstructions based on ice cores in depth for the now published study. For the first time they took into account that the winter temperature has a greater influence than the summer temperature in the recorded signal in the Antarctic ice cores. If this effect is included in the model calculations, the temperature fluctuations reconstructed from ice cores can also be explained by local climate changes in the southern hemisphere.

Thomas Laepple, who is currently conducting research at Harvard University in the US through a scholarship from the Alexander von Humboldt Foundation, explains the significance of the new findings: “Our results are also interesting because they may lead us out of a scientific dead end.” After all, the question of whether and how climate activity in the northern hemisphere is linked to that in the southern hemisphere is one of the most exciting scientific issues in connection with our understanding of climate change. Thus far many researchers have attempted to explain historical Earth climate data from Antarctica on the basis of Milankovitch’s classic hypothesis. “To date, it hasn’t been possible to plausibly substantiate all aspects of this hypothesis, however,” states Laepple. “Now the game is open again and we can try to gain a better understanding of the long-term physical mechanisms that influence the alternation of ice ages and warm periods.”

“Moreover, we were able to show that not only data from ice cores, but also data from marine sediments display similar shifts in certain seasons. That’s why there are still plenty of issues to discuss regarding further interpretation of palaeoclimate data,” adds Gerrit Lohmann. The AWI physicists emphasise that a combination of high-quality data and models can provide insights into climate change. “Knowledge about times in the distant past helps us to understand the dynamics of the climate. Only in this way will we learn how the Earth’s climate has changed and how sensitively it reacts to changes.”

To avoid misunderstandings, a final point is very important for the AWI scientists. The new study does not call into question that the currently observed climate change has, for the most part, anthropogenic causes. Cyclic changes, as those examined in the Nature publication, take place in phases lasting tens of thousand or hundreds of thousands of years. The drastic emission of anthropogenic climate gases within a few hundred years adds to the natural rise in greenhouse gases after the last ice age and is unique for the last million years. How the climate system, including the complex physical and biological feedbacks, will develop in the long run is the subject of current research at the Alfred Wegener Institute.

###

Notes for editorial offices:

Your contacts at the Alfred Wegener Institute are Prof. Gerrit Lohmann (Tel: +49(471)4831-1758; e-mail: Gerrit.Lohmann@awi.de), Dr. Martin Werner,Tel: +49(471)4831-1882; e-mail: Martin.Werner@awi.de) and Dr. Thomas Laepple (Thomas.Laepple@awi.de). Your contact in the Communication and Media Department is Ralf Röchert (Tel: +49 (0)471 4831-1680; e-mail: medien@awi.de).

The original title of the publication to which this press release refers is: Laepple, T., M. Werner, and G. Lohmann, 2011: Synchronicity of Antarctic temperatures and local solar insolation on orbital time scales. It will be published in the magazine Nature on 3 March 2011 (doi:10.1038/nature09825).

You will find printable pictures at: www.awi.de

The Alfred Wegener Institute conducts research in the Arctic, Antarctic and oceans of the high and mid latitudes. It coordinates polar research in Germany and provides major infrastructure to the international scientific community, such as the research icebreaker Polarstern and stations in the Arctic and Antarctica. The Alfred Wegener Institute is one of the seventeen research centres of the Helmholtz Association, the largest scientific organisation in Germany.

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wayne

“models can provide insights into climate change”
&
“To avoid misunderstandings, a final point is very important for the AWI scientists. The new study does not call into question that the currently observed climate change has, for the most part, anthropogenic causes.”
Knew it was in there somewhere… nothing new here… move along.

Jeff

I’ve seen more solid evidence from throwing chicken bones than these guys can conjure from their ice cores and sediments …. they are guessing on a grand scale with no true underlying theory …

Jeff Wiita

Why the disclaimer near the end of the article?
“To avoid misunderstandings, a final point is very important for the AWI scientists. The new study does not call into question that the currently observed climate change has, for the most part, anthropogenic causes.”
REPLY: It is what came with the press release, go figure – Anthony

frederik wisse

How big was the subsidy received for this document ?

Tom in Florida

“For the first time they took into account that the winter temperature has a greater influence than the summer temperature in the recorded signal in the Antarctic ice cores. If this effect is included in the model calculations, the temperature fluctuations reconstructed from ice cores can also be explained by local climate changes in the southern hemisphere.”
Does this simply mean they changed the parameters of the model and got a different result?

Bomber_the_Cat

“To avoid misunderstandings, a final point is very important for the AWI scientists. The new study does not call into question that the currently observed climate change has, for the most part, anthropogenic causes.”
Well,of course it doesn’t. It is a study of ice core records which, of course, do not provide information on the last century.
So why is it ‘very important for the AWI scientist’s to say this? Simple. If they don’t say this, they don’t get any more research funding – and what could be more important than that?

cedarhill

Thus the Antarctica can be isolated and handed off as “local only”. This is simply great news for the worshippers of AGW since it will eliminate the coldest places on Earth. This elimination will make (surprise!!) the Northern Hemisphere even “hotter” due to the concentration of Western industry and all those billions living north of the equator (think China, India, EU, US, USSR, etc).
Never forget – the Left plays chess but only plans a strategy that is no more than four plays ahead. They rely on the “public” being perpetual checkers players regarding science. That is when they take time away from the Charlie Sheens and Paris Hiltons.

TerryS

To avoid misunderstandings, a final point is very important for the AWI scientists. The new study does not call into question that the currently observed climate change has, for the most part, anthropogenic causes.

Or in other words: “Please let our paper through and don’t interfere with our grants “

The drastic emission of anthropogenic climate gases within a few hundred years

.. has since 1750 increased the number of CO2 molecules from three to four per other ten thousand molecules in the air.
The disclaimer is of big necessity when dealing with ice core data, because GISP2 or Vostok II ice cores show that the natural climate variability is immense and modern era is in no way indistinguishable from it. Except the Hockey stick of course.

Darkinbad the Brightdayler

That last comment makes it look as if someone has hitched a donkey to the stagecoach at the last minute.
If the Authors did, they’ve just downgraded their work from interesting to unlikely.

Baa Humbug

“To avoid misunderstandings, a final point is very important for the AWI scientists. The new study does not call into question that the currently observed climate change has, for the most part, anthropogenic causes.”

Interpretation: Please fellas, don’t unleash your fury at us, we really do believe in AGW and wish to be able to continue publishing in prestigeous journals and have our share in the great AGW honey pot. Oh! A special hello to Gavin S and Michael M, we love them and admire their work.

Gator

“The drastic emission of anthropogenic climate gases within a few hundred years adds to the natural rise in greenhouse gases after the last ice age and is unique for the last million years. ”
Yes. And so is Rock music. So what? This will be remebered as “The Carbon Age” unfortunately, and not “The Age of Enlightenment”.

John Brookes

Bit cynical here, aren’t we?

Scott Covert

“To avoid misunderstandings, a final point is very important for the AWI scientists. The new study does not call into question that the currently observed climate change …..”
Anthony, maybe if you added this to the end of your paper you would find it easier to get it published. /sarc

Jeff Wiita says: March 3, 2011 at 4:53 am
Why the disclaimer near the end of the article?
“To avoid misunderstandings, a final point is very important for the AWI scientists. The new study does not call into question that the currently observed climate change has, for the most part, anthropogenic causes.”

By inference they are saying this could be construed as calling into question the causation of “currently observed climate change“, and furthermore something is very important for the AWI scientists.
What is very important? That is the real question … And they answer it!
Note it does not say: “it is very important there is no misunderstanding“, it says: “a final point is very important“, and the final point is manmade causation. This means that the important point for the AWI scientists is not avoiding misunderstanding but avoiding calling into question the manmade causation.

jack morrow

They also should have included a “smiley face” at the end also.

Coach Springer

FTA: “The drastic emission of anthropogenic climate gases within a few hundred years adds to the natural rise in greenhouse gases after the last ice age and is unique for the last million years.”
Define drastic. Anthropogenic climate gases vs. Natural climate gases within a few hundred years? Unique? For the last million years? Propaganda, impure belief and no science in the all important disclaimer.

Scott Covert

“Juraj V. says:
March 3, 2011 at 5:44 am
The drastic emission of anthropogenic climate gases within a few hundred years
.. has since 1750 increased the number of CO2 molecules from three to four per other ten thousand molecules in the air.
The disclaimer is of big necessity when dealing with ice core data, because GISP2 or Vostok II ice cores show that the natural climate variability is immense and modern era is in no way indistinguishable from it. Except the Hockey stick of course.”
That’s because in Hockey, the blade of the stick is where the ice stops and the wood begins.
(I’m a quote of the week machine!)
Maybe the whole AGW thing is why hockey sticks are made from pure carbon now.

UK Sceptic

So how much can the bottom of the AGW BS barrel be scraped before it ceases to exist?

Joe Polunc

Trying to be too clever here just got them busted. Oh we can debate paleoclimate ice cores all day but all the recent AGW data is rock solid and irrefutable. How stupid do they think we are?

Joe the Blogger

Trying to be too clever here just got them busted. Oh we can debate paleoclimate ice cores all day but all the recent AGW data is rock solid and irrefutable. How stupid do they think we are? OK, tin foil hat back on.

REPLY: It is what came with the press release, go figure – Anthony
It will be nice when the world is finally over this global warming epoch. But then something else will take its place.

John Brookes says:
March 3, 2011 at 6:05 am
“Bit cynical here, aren’t we?”
Gee, I wonder why?
/sarc
BTW Anthony, mods and fellow WUWT addicts: INGSOC is dead. I will henceforth use TrueNorthist for all my posting. I was using a couple of different names for different sites and that was confusing if not misleading.
Cheers!
Dave

Slabadang

A new partyline publication!
All publications had to end with a confirmation of ideology in case anyone happened to doubt that the message partly included “contra revolutionary” statements or conclusions.
Slava slava Sovjetski kommunism “Long live the partyline!”

To avoid misunderstandings… The new study does not call into question that the currently observed climate change has, for the most part, anthropogenic causes… The drastic emission of anthropogenic climate gases within a few hundred years … is unique for the last million years.

All this goes back to defending the methodology of the ice core CO2 measurements (in which CO2 is supposedly not lost) which still leads to the second infamous Hockey Stick, the Ice Hockey Stick, and which on the grounds of shape alone, to say nothing of methodology, I regard as suspicious and long, long overdue for audit.
Once again, read Jaworowski. My strong feeling is that here is another example of good science being lost to bad in recent times – cf Lamb’s climate science to that of his successors Wigley and Jones, bent to alarmism and trapped by the IPCC.

APACHEWHOKNOWS

Re-runs.

Olen

If climate change scientists had practiced accepted standards of honesty and morality by their actions there would be no question of integrity.
The disclaimer is, let us not have any misunderstanding. Witness good science having to beg off on their research by making it clear they support man made climate change theory.
The highest form of political corruption is to use tax dollars to promote a political agenda that always involves tax payer money.

Splicing the CO2 ice core data with present day measurements produces a great hockey stick. http://www.kidswincom.net/climate.pdf.

spectacular
UAH
Delta (2010 05 – 2011 02) = + 1,056ºC
The presumed change in 150 years that occurred in a few months.
For the first time they took into account that the winter temperature has a greater influence than the summer temperature in the recorded signal in the Antarctic ice cores.
or
For the first time they took into account that the summer temperature has a greater influence than the winter temperature in the recorded signal in the in tree rings.
Any Resemblance is Purely Coincidental.
National Hockey League (NHL)

Latitude

The new study does not call into question that the currently observed climate change has, for the most part, anthropogenic causes.
===============================================
hostile reviewer

TomRude

“For the first time they took into account that the winter temperature has a greater influence than the summer temperature in the recorded signal in the Antarctic ice cores. If this effect is included in the model calculations, the temperature fluctuations reconstructed from ice cores can also be explained by local climate changes in the southern hemisphere.”
For the FIRST time? LOL

Steve Keohane

The drastic emission of anthropogenic climate gases within a few hundred years adds to the natural rise in greenhouse gases after the last ice age and is unique for the last million years.
One adjective and one adverb too many for a scientific statement. Just more BS to try to rewrite history.
http://i46.tinypic.com/2582sg6.jpg
One good point raised is that the SH may have local climactic events like the NH. /sarc

Noblesse Oblige

“The new study does not call into question that the currently observed climate change has, for the most part, anthropogenic causes.”
Not so fast. This disclaimer, now as common as the Miranda warning, is not quite right. The “book” ice age scenario, as promoted largely by the well funded Scripps gang, says that the reason for the lag between CO2 and temperature at the onset of glaciations and interglaciations is driven by the Milenkovich cycle driven changes in the North. This says all bets are off.

James Sexton

Hmm…..so, reconstructed temps may not be a proxy for world temps……….of which much of CAGW/CC theory hinges upon………but this doesn’t refute that………..????? uhmm….

tadchem

Shortly after Galileo’s revolutionary claims regarding empirical evidence of the blasphemous motions of the planets and their satellites, other researchers were in a quandary. It was difficult to report factually accurate data without challenging the established orthodoxy. The facts and the theory were so disparate that to support one would make it hard not to be seen as denying the other. OTOH, supporting orthodoxy meant denying empirically verifiable facts. The result was a matter-of-fact reporting style for data that avoided theoretical implications, and lip service to the established position. Only the widespread Protestant denial of Papal authority allowed unorthodox theoretical developments to flourish.
History does repeat itself. This time the IPCC is cast in the role of the Pope.

G. Karst

These standard AGW disclaimers are scientifically embarrassing. What is wrong with these people? Since when do peer reviewed papers, directly tell us, what something doesn’t mean?! Is that something like an anti-conclusion?? I must have skipped that paragraph inside the scientific method. These people declare themselves as “non-scientists with science degrees”, with such statements. STOP IT! GK

G. Karst

Fred H. Haynie :
http://www.kidswincom.net/climate.pdf.
Your presentation was excellent! THX GK

Jimbo

“The new study does not call into question that the currently observed climate change has, for the most part, anthropogenic causes.”

Of course it call it into question otherwise why mention it? Does the disclaimer have anything to do with getting past peer review? Continued funding perhaps?

RHS

At least they didn’t end their paper with /sarc

John from CA

I didn’t read all the comments so I apologize if someone already pointed this out.
For the first time they took into account that the winter temperature has a greater influence than the summer temperature in the recorded signal in the Antarctic ice cores. If this effect is included in the model calculations, the temperature fluctuations reconstructed from ice cores can also be explained by local climate changes in the southern hemisphere.
For the first time they took into account…? Where do they think the ice came from if not from snow pack? Of course “winter temperature has a greater influence than the summer temperature in the recorded signal”, its Ice.
You just can’t make this “stuff” up!
Does this simply mean they changed the parameters of the model and got a different result?

The disclaimer at the end is simple. Any time they discover something new, or correct something old, or expand a theory, or refine a theory, they know with certainty
that somebody will say ” new interpretation of Ice core? does that mean C02 doesnt cause warming?” and other stupid non sequitors. They know they are going to get a flurry of uniformed cites of their press release that try to spin it into an AGW-is-wrong story. So these disclaimers are being put in to prevent that.
Personally if I had to deal with some of the ways both sides misuse press releases, I’d put these kind of disclaimers in

John from CA

Tom in Florida says:
March 3, 2011 at 5:13 am
“For the first time they took into account that the winter temperature has a greater influence than the summer temperature in the recorded signal in the Antarctic ice cores. If this effect is included in the model calculations, the temperature fluctuations reconstructed from ice cores can also be explained by local climate changes in the southern hemisphere.”
Does this simply mean they changed the parameters of the model and got a different result?
==========
I pulled the quote, from Tom in Florida says: March 3, 2011 at 5:13 am and inadvertently left his question in the post.
Interesting question but the issue of glacial ice formation and the validity of the Ice Core and subsequent model “assumptions” are, IMO, the real question.

Ted

TO ENSURE THE GRANT MACHINE KEEPS PROVIDING AND PLACATE THE AGW WARMISTS.
They never change do they!
To avoid misunderstandings, a final point is very important for the AWI scientists. The new study does not call into question that the currently observed climate change has, for the most part, anthropogenic causes. Cyclic changes, as those examined in the Nature publication, take place in phases lasting tens of thousand or hundreds of thousands of years. The drastic emission of anthropogenic climate gases within a few hundred years adds to the natural rise in greenhouse gases after the last ice age and is unique for the last million years.

#
#
James Sexton says:
March 3, 2011 at 7:57 am
Hmm…..so, reconstructed temps may not be a proxy for world temps……….of which much of CAGW/CC theory hinges upon………but this doesn’t refute that………..????? uhmm….
#########
AGW theory doesnt rest or hinge on reconstructed temps.
It rests on the theory of tyndall gases.
That theory holds that increasing tyndall gases in the atmosphere will increase
temperatures.
The unanswered question for this theory is HOW MUCH warmer and what
kind of benefit or damage will that warming cause.
Lets be clear on that because most proponents of AGW dont even say
what is core to their theory. The core element is tyndall gas theory. The
unexplored element of that theory is how MUCH will the globe warm.
when and where.
A first order estimation of the warming is 1.2C per doubling of C02. This first order estimation assumes that everything else remains constant: constant insolation, all other forcings stay the same, no feedbacks. But we know other things dont remain
constant.
To get a HANDLE on what happens when other things change you have these
two options:
1. Look at the past
2. project the future.
By looking at the past the hope is to get a sense of how important the tyndall gas effect is relative to other changing forcings. So paleo gives you a range of estimates
for the sensitivity. By looking at observations you can also get a range.
By constructing models of the climate and projecting the future you can also get a sense of the importance of tyndal gases and other effects.
So, paleo and projections are not really key to the fundamental core of AGW.
They are more central to CAGW scare. But if you look at the real theory, which is
the tyndal gas theory ( more GHG = more warming) then you’ll understand better.

Brian H

Karst, Haynie;
“freezing and thawing of sea ice is the factor that causes the observed seasonal variation in carbon dioxide concentrations.” (Slide 15)
Finally! A potent reason to track sea ice!

cal

A year or two ago I posted on WUWT asking if anyone knew why Milankovitch believed that the cycles were linked to the insolation in the Northern Hemisphere because I felt it should be linked to the Southern. No one responded. Now this paper states that Milankovitch believed this because the land responds more dynamically than the sea. I find this intriguing since this was my logic for believing the reverse!
My logic was that the earth has a built in negative feedback due to the fourth power radiation law. To a first approximation it means that to induce the +/- 2% temperature change of a typical ice age and subsequent interglacial one needs a +/- 8% insolation change. Since no one was suggesting that the Milankovitch cycles induced a power change of this magnitude one had to look for some sort of intergration of the cooling and warming effects where this could take place without the surface warming or cooling.
There was a plausible explanation for the cooling cycle already since the covering of the land with ice would increase the albedo and thus reduce the effective insolation. However the problem with this scenario is that the start of the interglacial is characterised by the fastest rate of warming over the whole 100,000 year cycle. If the ice albedo was such a powerful influence how did the effect not stop the rapid warming when it was at it maximum impact? Even more importantly the melting of ice requires a huge amount of energy. If the ice is over land pretty well all this has to come from insolation changes at the time the melting takes place. This compounded the problem about where the energy was coming from.
However over the sea (which is dominant in the Southern Hemisphere ) there is the potential for a lot of energy build up. If the ice projects over the sea (as it does now) it is effectively insulating the sea from radiating to space. Thus as the insolation in the tropics increases the energy is moved away by evaporation and subsequent snow due the high winds that would accompany a big temperature difference between the tropics and the poles. Energy is also moved via the sea currents which would flow under the ice and melt it from below. Thus in this case the tropical energy would be dissapated in the latent heat of fusion of ice and latent heat of water vapour although some amount of these latent heats would be released when the snow forms. The key thing is that the temperature at the tropics and the poles would not fully reflect the change in insolation and so the normal increase in radiation that would accompany a rising land temperature would not happen.
In my model this might carry on for perhaps a thousand years until the sea ice becomes thin enough for it to vanish during the summer. Then there would be a dramatic change. The sea, now exposed, would be relatively warm and the tropics would no longer be swept by such strong winds as the climate becomes more equable and with less condensation at the poles we might expect an increased humidity (and consequent greenhouse warming) but perhaps not so much as to induce a lot of cloud cover. Thus a dramatic rise in temperature on the land might be expected.
Of course it is all conjecture but now I know Milankovitch was guessing also I do not feel so bad about it!

M White

“Antarctic ice sheet built ‘bottom-up'”
http://www.bbc.co.uk/news/science-environment-12619342

John from CA

steven mosher says:
March 3, 2011 at 10:36 am
. . .
So, paleo and projections are not really key to the fundamental core of AGW.
They are more central to CAGW scare. But if you look at the real theory, which is
the tyndal gas theory ( more GHG = more warming) then you’ll understand better.

======
Your comments are always a great read.
Here’s the problem with the tyndal gas theory. Though its a reasonable conclusion from Lab experiments, its relationship/impact on the climate system is poorly understood. Its poorly understood because the climate system is poorly defined.
The theory doesn’t support current observation. We have satellites in space quantifying regional concentrations of CO2, water vapor, and temperature [ etc.] yet the regional temperature comparisons to CO2 concentrations do not reflect regional warming. If they did then the theory would hold so we’re logically left with natural causes.
If the theory is valid beyond the Lab, where is the evidence of CO2 impact today?

Taphonomic

With regard to the disclaimer:
“The drastic emission of anthropogenic climate gases within a few hundred years adds to the natural rise in greenhouse gases after the last ice age and is unique for the last million years.”
Note the cherrypicking of “unique for the last million years”. This allows them to conveniently overlook the Miocene Epoch (~23 to 5 million years ago) during which CO2 was much higher than it currently is. How DID the world survive?

Brian H said on New interpretation of Antarctic ice cores
March 3, 2011 at 10:48 am
Brian,
When you turn on the faucet (at the equator) and stopper the sink drain (in the Arctic) we should expect the level in the sink to rise. Unplug it and the level goes down.