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.
Arctic Blooms Occurring Earlier: Phytoplankton Peak Arising 50 Days Early, With Unknown Impacts on Marine Food Chain and Carbon Cycling
http://www.sciencedaily.com/releases/2011/03/110302171320.htm
Fred;
Marvelous document…
Edit notes: (your email is a deep milsec secret, so I’ll post them here)
increasing it’s density [its]
sequester(er)
were water freezes [where]
does not contributed significantly [contribute]
rises that cause it’s emission [its]
You’re searching still for peer reviews, I gather. Maybe Freeman Dyson would oblige; he’s a bio-cycle advocate, so would give your thesis a good going-over. Failing that, there are probably contacts/people at SEPP who could help. (sepp.org, when it recovers from reconstruction). Also sppiblog.org, and thegwpf.org.
That final paragraph can be replaced with a one-word statement more fitting to the AGW dogma: Amen.
cal says: (March 3, 2011 at 11:04 am)”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.”
Remember that 12,000 years ago earth’s axis tilt was moving towards the max of 24.5 degrees and NH summer solstice was approaching perihelion. The combination of those conditions would be the trigger that began the melting of the great ice sheets.
Slabadang says:
March 3, 2011 at 7:12 am
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!”
That’s exactly what the last paragraph reminded me of: An acknowledgement of the superiority of communist dogma was required somewhere in any published research in East Germany. Faithful scientists incorporated this affirmation of the party line creatively in the main text, preferably properly embedded with relevant connections established to the subject of study. Well, and if one couldn’t be bothered or got too carried away just researching, one’s boss would point out that it was missing and needed to be included if one wanted to enjoy a successful career.
Given the vitriol heaped on anyone straying from the partyline, that such a Post Scriptum should be seen as necessary for mainstream researchers working in any climate related field today is not at all surprising. By itself, that paragraph does not allow one to draw conclusions on whether the authors are fervent believers or not, and it also does not automatically devalue the findings in the paper at all, in my view.
Especially since these findings challenge an important and long established theory of large scale climate change.
The disclaimer seems to be a product of the press release, as ever. A quick perusal of the paper does not find anything along these lines.
One wonders why the authors of such papers put up with the spin from their institutes PR departments.
Lucy Skywalker says:
March 3, 2011 at 7:13 am
Once again, read Jaworowski. My strong feeling is that here is another example of good science being lost to bad in recent times.
Fred H. Haynie says:
March 3, 2011 at 7:22 am
Splicing the CO2 ice core data with present day measurements produces a great hockey stick. http://www.kidswincom.net/climate.pdf.
Fred and Lucy,
Even without any present day splicing, the ice core CO2 shows a nice hockeystick over the past centuries. A real one, based on real measurements, not an imaginary one, based on proxies:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/antarctic_cores_001kyr_large.jpg
The ice cores used have quite different temperature profiles and accumulation rates, the fastest ones (2 out of 3 Law Dome cores) have a resolution of about 8 years and the core was completely above the clathrate formation level for CO2. Despite that, CO2 levels are about the same for the same average gas age for all cores.
But the Law Dome ice cores also have a 20 years (1958-1978) overlap with the South Pole atmospheric measurements:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/law_dome_sp_co2.jpg
A similar (opposite) HS can be seen in the direct measurements of calcite layers in coralline sponges:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/sponges.gif
Again a HS based on real measurements, real data.
I have read and commented on what Jaworowski says:
http://www.ferdinand-engelbeen.be/klimaat/jaworowski.html
If anyone can explain me that cracks in the ice core can lead to lower (180-300 ppmv) CO2 levels at measuring time, while the outside air is at 390 ppmv, I am very interested.
BTW Fred, any CO2 clathrate left in the ice core would decompose, even explosively, under the vacuum applied during the measurements. Further, an alternative method used is by sublimating everything under vacuum and selectively freezing the different compounds out cryogenically. How much clathrates will be left with that method?
The biggest impossiblility that Jaworowski shows, while accusing Neftel of fraud, is that he doesn’t seems to know that there is a difference between ice age and enclosed gas age. He simply takes the wrong column (ice age instead of gas age) in the table of Neftel. This kind of mistake is impossible for an ice researcher.
Thus sorry, I can’t take anything that Jaworowski said seriously. Moreover, his objections were from 1992 and before. Nothing new since then. All of his objections were already rejected by the work of Etheridge e.a. in 1996.
Fred H. Haynie says:
March 3, 2011 at 11:30 am
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.
Except that the d13C level shows that it isn’t the oceans: the d13C levels should go up with more CO2 from the oceans, but we see a huge drop in d13C level together with the CO2 increase in winter, thus the source is vegetation decay. In summer we see the reverse: a sharp decline in CO2 when leaves start to grow in the mid-latitudes, while d13C levels increase.
Ferdinand Engelbeen said on New interpretation of Antarctic ice cores
March 3, 2011 at 3:17 pm
Ferdinand,
There is a linear inverse relationship between the atmospheric amount of CO2 and the the isotope depletion data. This is the result of how the index is calculated. If you assume that CO2 from inorganic sources has an index of the PDB standard and CO2 from organic origin has the graphite standard, you can calculate the fractions of each type in the atmosphere. I have done this and the organic fraction is around one third of the total. Of that fraction, most comes from the decay of organic matter, and most of that comes from the ocean. Study my presentation http://www.kidswincom.net/climate.pdf with an open and objective mind.
The Antarctic ice core temperature data matches (or let’s say an explanation can be made for why it partially matches) the northern hemisphere Milankovitch Cycles. They do not match the southern hemisphere cycles at all which have different timing.
Hence, the need to invoke “winter temperatures” in the new explanation. Winter temperatures at the south pole would be close to -70C in the ice ages. I don’t think -60C versus -70C is going to make much difference.
But a funny thing happens in the Milankovitch Cycles that is not really mentioned very often. Solar insolation in the winter is actually higher than today in the ice ages so winter temperatures are not as affected as summer temperatures (as long as the location is not on top of a mile of ice). South Texas might have been about the same temperature as today during the winter in the ice ages but cooler in the summer.
The sea ice around Antarctica greatly expanded versus today in the ice ages. At 45S, temperatures would have similar to today in the winter but much cooler in the summer. The ice just did not melt whereas it does today. So, a simple thing such as the axial tilt (which has the same impact in the north as in the south) could explain why Antarctica matches the northern (axial tilt dominated) Milankovitch Cycles.
Having said that, it appears the Antarctic ice cores are mostly leading the changes that occur in the ice ages. We don’t have really good resolution estimates for the north so it could actually be the other way around.
I read the supplementary to the paper and the authors have really crunched all the numbers here so their explanation could be right.
It is important not to get too hung up on their final parting words of conventional “wisdom”.
There are several interesting points coming out of this research:
Firstly that we do not live in a global climate, but rather in two, only partly connected hemispherical climates (possible in reality in a number of poorly connected local climates, but that is outside their study).
Secondly, the importance of considering maximum and minimum termperatures seperately.
At the poles, the winter is most important.
In the eastern half of temperate Australia, I have found that the maximum temperatures are more important than minumums when you are trying to establish trends.
In Sydney, the actual seasonal and monthly maximum trends can tell you most about the climate and how the measured temperature is driven by very, very local UHI effects. Remove the UHI and there is no trend since 1866.
So there’s much to think about in this paper, as long as you eliminate the last few lines which contain the obligitory poem to the pagan AGW god.
Just more yellow journalism. Google yellow journalism to learn more.
The future can not be foretold, even with a modern crystal ball (a monitor with a computer model running).
“Our results are also interesting because they may lead us out of a scientific dead end.” “Now the game is open again and we can try to gain a better understanding […]”
Refreshing.
Tom in Florida says:
March 3, 2011 at 12:38 pm
(ref:cal says: (March 3, 2011 at 11:04 am))
Remember that 12,000 years ago earth’s axis tilt was moving towards the max of 24.5 degrees and NH summer solstice was approaching perihelion. The combination of those conditions would be the trigger that began the melting of the great ice sheets.
Of course the changes in the tilt and obliquity etc. cause the change in insolation that increases the energy reaching the earth. My point is that the variation in energy does not seem to be enough to account for the temperature excursion. This was always the cry from the AGWers who originally tried to play down the importance of the Milankovitch cycles and, instead focus on the “positive feedback” due to the related CO2 release amplifying the effect. That of course ignoring the facts 1) the rapid warming was actually taking place when the CO2 was at a minimum 2) CO2 only increased after the temperature rise 3) The temperature rise stopped abrubtly while the CO2 was at its maximum. This clearly was not the answer.
When you see this sort of oscillation one looks for a driven resonant circuit with high capacitance and that is what I was suggesting. My argument is also that the maximum air temperature may well coincide with the maximum insolation in the North because that is when the highest proportion of the insolation will be retained by the land and air. However my conjucture is that the greatest accumulation of energy might well occur in the Southern ocean in the period preceding this.
Fred H. Haynie says:
March 3, 2011 at 4:35 pm
Of that fraction, most comes from the decay of organic matter, and most of that comes from the ocean. Study my presentation http://www.kidswincom.net/climate.pdf with an open and objective mind.
The overall decline of d13C is about 1/3rd of what is expected from the addition of humans burning fossil fuels (at -24 per mil VPDB) over the past 160 years (and beyond). But while the difference is caused mainly by deep ocean CO2, the latter can’t be additional, as that would lead to an increase of CO2 three times higher than from human induced CO2 alone. In reality, the increase of total CO2 is only halve the human addition, thus the smaller reduction of d13C than expected is from deep ocean throughput over the seasons (back and forth, not one-way). One can calculate the deep oceans throughput (at near zero per mil d13C), based on the d13C differences (ocean surface and vegetation have far less influence on d13C levels):
http://www.ferdinand-engelbeen.be/klimaat/klim_img/deep_ocean_air_zero.jpg
For intra annual changes, it is quite clear that land vegetation is responsible for the rapid increase and decrease of CO2 over the seasons, as the d13C drop and rise shows, especially over the NH, where far more land resides. For the multi-annual increase, humans are to blame…
And yes, I have read your work with an open and objective mind, as I always do with one’s work. I have a lot of remarks on your work, but this is not the place to do that. Only about the ice cores, which is important here: you are too much influenced by Jaoworowski, who’s remarks simply don’t hold, even are physically impossible.
This nonsense disturbed my equilibrium, they say that the antarctic ice cores are the result of southern hemisphere weather and not the result of the climate from the northern hemisphere. Who would imagine that this could be possible, the planet that these people are from must have a two dimensional one sided climate conveyor system and they are totally surprised by this finding. I have been under the impression that when it is cold in the north it is warmer in the south and vise versa, so now they want a grant to prove this. The mandatory mention of the AGW is man made is a plea for more money. Science is meant to be above this [snip . . nonsense?].
Ferdinand,
Give me a logical reason why there is a divergence between using CO2 as a temperature proxy and isotope depletion as a temperature proxie begining around 6000 years ago; and why the CO2 proxie produces unrealistic temperatures in the last century.
Tell my why the most seasonal variation in CO2 is observed in the arctic where their are few trees and practically no seasonal variation around the equator where there are rain forests.
Fred H. Haynie says:
March 4, 2011 at 5:01 am
Give me a logical reason why there is a divergence between using CO2 as a temperature proxy and isotope depletion as a temperature proxie begining around 6000 years ago; and why the CO2 proxie produces unrealistic temperatures in the last century.
I shouldn’t use CO2 as a temperatur proxy at all, as there are better ones (d2H and d18O) and d13C as a temperature proxy doesn’t sound that reliable to me too. There was a quite stable ratio between temperature proxies and CO2 levels over the past 800,000 years (CO2 always lagging temperature), but that doesn’t hold anymore since humans started to emit CO2 from fossil fuels.
Tell my why the most seasonal variation in CO2 is observed in the arctic where their are few trees and practically no seasonal variation around the equator where there are rain forests.
An even larger seasonal variation is found in mid-latitudes, but as these variations are over land, these are not used for “background” CO2 levels. See e.g. Schauinsland, mid the Black Forest in Southern Germany at 1,000 m high:
http://cdiac.ornl.gov/trends/co2/uba/uba-sc.html
and compare that to the variability in e.g. Alert (NW Territories, Canada):
http://cdiac.ornl.gov/trends/co2/csiro/csiro_alt.jpg
In the mid-latitude background stations and surely at 3,400 m height (Mauna Loa), the amplitude is lower, because the regional seasonal effect is already diluted by the air masses over the oceans. The polar stations receive air directly from the mid-latitudes by the Ferrel cells:
http://en.wikipedia.org/wiki/Atmospheric_circulation
The tropics show little variation, as there is not such a big variation in temperature causing complete defoliage of a lot of trees in fall and fast regrowth in spring. But look at the seasonal changes in oxygen and compare that to the seasonal change in total CO2 in Barrow:
http://www.bowdoin.edu/~mbattle/papers_posters_and_talks/BenderGBC2005.pdfThe O2 levels go up when CO2 levels go down. The same for d13C levels and CO2 levels:
http://www.barrettbellamyclimate.com/page34.htm
This makes it clear that seasonal changes in CO2 levels are caused by vegetation, not by the oceans (via ice cover or temperature).
cal says: (March 4, 2011 at 1:00 am)
“Of course the changes in the tilt and obliquity etc. cause the change in insolation that increases the energy reaching the earth. My point is that the variation in energy does not seem to be enough to account for the temperature excursion..”
My point was simply that when the NH ice sheets disappeared those were these conditions: 12,000 years ago earth’s axis tilt was moving towards the max of 24.5 degrees and NH summer solstice was approaching perihelion. However the current eccentricity is low and that would possibly extend the interglacial a few thousand years.
“In fact, it turns out that these large year-to-year fluctuations in the rate of atmospheric accumulation are tied to temperature changes, which are in turn due mostly to El Nino, La Nina, and volcanic eruptions. And as shown in the next figure, the CO2 changes tend to follow the temperature changes, by an average of 9 months. This is opposite to the direction of causation presumed to be occurring with manmade global warming, where increasing CO2 is followed by warming.”
This according to Dr Roy Spencer. The entire article and supporting graphs of EMPIRICAL evidence can be found here…
http://www.drroyspencer.com/2009/01/increasing-atmospheric-co2-manmade%E2%80%A6or-natural/
Dr Spencer wrote this 2 years ago and ends with this simple statement, “If an expert in this subject sees a major mistake I’ve made in the above analysis, e-mail me and I’ll post an update, so that we might all better understand this issue.”
There have been no updates, feel free to contact Dr Spencer if you disagree.
Gator says:
March 4, 2011 at 7:23 am
Dr Spencer wrote this 2 years ago and ends with this simple statement, “If an expert in this subject sees a major mistake I’ve made in the above analysis, e-mail me and I’ll post an update, so that we might all better understand this issue.”
There have been no updates, feel free to contact Dr Spencer if you disagree.
There was a reaction by me, and Dr. Spencer nicely published it the next day, together with his comment:
http://www.drroyspencer.com/2009/01/the-origin-of-increasing-atmospheric-co2-a-response-from-ferdinand-engelbeen/
The main problem with Dr. Spencer’s interpretation is that he looks at the CO2 increase rate (the variability around the trend), which is highly dependent on temperature with some lag, but that doesn’t say anything about the cause of the trend itself, which is (near) completely caused by human emissions…
Hey Ferdinand! I said if you find a fault, take it up with the good Dr. You claim to know it all, now go tell Dr Spencer where he has gone so terribly wrong. He has asked for this very input, now get going. Don’t sit there arguing with me, this was not my article. I gave you the link, now man up. Geesh!
Ferdinand,
I agree that CO2 is not a good proxie for temperature, but that is what CAGW is all about, climate sensitivity. The divergence shows that it is not a good proxie. Are you trying to say that climate sensitivity is greater or lesser to anthropogenic sources than natural sources?
There is no significant longitude effect on background levels of CO2. At the same latitude and season, the concentrations are the same over land and over sea. There is a lot more sea doing it’s thing than trees in the mid latitudes doing their thing.
Gator says:
March 4, 2011 at 8:23 am
You wrote:
There have been no updates, feel free to contact Dr Spencer if you disagree.
Which was what I have done. There is not a formal “update” by Dr. Spencer, but he published my comment, without any comment on the fact that he used the increase rate, not the increase itself. Does that mean that he agrees with my comment? I don’t know, but you can’t say that there was no update, if there was an immediate reaction without rebuttal…
Hey Ferdinand! I read your letter and Dr Spencer’s comments. Apparently he does not agree with your assertion and has not felt it necessary to update his piece. I also do not buy your arguments, they fly in the face of my training, and logic. But feel free to try and get an update from Dr Spencer, you will get none from me.