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.
“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.
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 …
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
How big was the subsidy received for this document ?
“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?
“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?
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.
Or in other words: “Please let our paper through and don’t interfere with our grants “
.. 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 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.
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.
“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”.
Bit cynical here, aren’t we?
“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.
They also should have included a “smiley face” at the end also.
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.
“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.
So how much can the bottom of the AGW BS barrel be scraped before it ceases to exist?
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?
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
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!”
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.