CO2 Does Not Drive Glacial Cycles

Guest post by Steven Goddard

There are still people who insist that changes in CO2 can explain the pattern of glacial and interglacial periods.  This article will present several arguments demonstrating that is incorrect, based on the ice core data below.

http://www.brighton73.freeserve.co.uk/gw/paleo/400000yearslarge.gif

Click for larger image

The most obvious reason is that CO2 lags temperature.  Changes in ocean temperature have driven the changes in atmospheric CO2, as explained here.  CO2 is not the driver.

Now consider the earth 20,000 years ago.  Temperatures were low – about 8C cooler than the present.  Due to the cold ocean temperatures, levels of atmospheric H20 (the primary greenhouse gas) were low.  CO2 levels were also low, at about one half current levels.  The earth’s albedo was very high due to extensive ice cover which had much of North America and Europe buried in ice.   Using the popular “CO2 and feedbacks explain everything” theory, all of these negative feedbacks should have driven earth further and further into an irrecoverable ice age.  Cold ocean water should have continued to absorb more CO2 from the atmosphere.

Atmospheric H2O should have continued to decline due to lower vapor pressures over the cooling oceans.  Albedo should have continued to increase due to expanding glaciers further from the poles.  All of these negative feedbacks should have caused temperatures to decrease further, and the death spiral should have continued.  But none of these things happened.  Instead, the earth warmed very quickly.  CO2 was absolutely not the driver, and positive/negative feedbacks had to be in balance.

Consider the earth 14,000 years ago.  CO2 levels were around 200 ppm and temperatures, at 6C below present values, were rising fast.  Now consider 30,000 years ago.  CO2 levels were also around 200 ppm and temperatures were also about 6C below current levels, yet at that time the earth was cooling.  Exactly the same CO2 and temperature levels as 14,000 years ago, but the opposite direction of temperature change.  CO2 was not the driver.

Now consider 120,000 years ago.  Temperatures were higher than today and CO2 levels were relatively high at 290 ppm.  Atmospheric H20 was high, and albedo was low.  According to the theorists, earth should have been warming quickly.  But it wasn’t – quite the opposite with temperatures cooling very quickly at that time.  CO2 was not the driver.

If CO2 levels and the claimed lockstep feedbacks controlled the climate, the climate would be unstable.  We would either move to a permanent ice age or turn into Venus.  Warmer temperatures generate more CO2.  Increased CO2 raises temperatures.   Warmer temperatures generate more CO2 …… etc.  It would be impossible to reverse a warming or cooling trend without a major external event.  Obviously this has not happened.

An exercise to get people thinking for themselves.  If the temperature at some point in the past was 4C cooler than now and CO2 levels were 240 ppm, was the temperature going up or down?  There are ten points on the graph that match those conditions.  Half of them have rapidly rising temperatures and half have rapidly falling temperatures.  It becomes abundantly clear that there has to be another degree of freedom which is dominant in controlling the glacial cycles.

In the ice core record, temperature drives CO2 – not the other way around.   Sometimes the earth warms quickly at 180 ppm CO2.  Other times it cools quickly at 280 ppm CO2.  Again, CO2 is not the driver of glacial cycles – there has to be a different cause.

UPDATE:

The use of the term “negative feedback” in this article is the commonly understood meaning – i.e. feedbacks that drive temperature down. Technically speaking, this usage is incorrect. From a viewpoint of semantics, a negative feedback would be one that works against the current trend. This semantic difference has no relevance to the logic being presented in the article.

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Nick Stokes

Steve,
Who are these people “who insist that changes in CO2 can explain the pattern of glacial and interglacial periods”? I don’t think they include any regular climate scientists that I know of. There is a view that CO2 provides positive feedback to a change already under way.

rokshox

“Atmospheric H2O should have continued to decline due to lower vapor pressures over the cooling oceans. Albedo should have continued to increase due to expanding glaciers further from the poles. All of these negative feedbacks should have caused temperatures to decrease further…”
Ummm. Those are positive feedback mechanisms. The feedback signum refers to effect on signal amplitude, not the direction the signal changes.

Wondering Aloud

Way to not read carefully.

Steven Goddard

Nick Stokes,
Are you asking a serious question? The giant ice core graph was the centerpiece of Al Gore’s movie – in a clear, deliberate, unambiguous attempt to convince the audience that CO2 drives temperature cycles. Nearly every schoolchild in the world has been taught this concept.

Mike Ramsey

Nick Stokes (21:58:40) :
Steve,
Who are these people “who insist that changes in CO2 can explain the pattern of glacial and interglacial periods”?
http://www.sciencemag.org/cgi/content/abstract/289/5486/1897
“Hence, the 100,000-year cycle does not arise from ice sheet dynamics; instead, it is probably the response of the global carbon cycle that generates the eccentricity signal by causing changes in atmospheric carbon dioxide concentration.”

Bill D

My comment is bascially the same as Nicks. All of the science that I have read says that sun cyles drive the long term glacial cycles and that CO2 provides a positve feedback during the warming periods. It’s not just the simple solubility of CO2 in the oceans. Warming increases rates of bacterial degredation on land and in water, as well as making stronger thermal statification in the oceans. Thus, warming can lead to less CO2 burial in the ocean and more CO2 release from soils. Right now the tundra is a major reservoir of organic carbon. If warming and melting continue, releases from this source will increase.

Didjeridust

Of course there aren’t any of these people
This is just a way of trying to give the simple minds among the readers here the impression that there actually is people in the “AGW camp”, the “Alarmists”, “Climate hysterics” or whaetever, that holds this view.
“Science Blog of the year” – Yeah, right!

REPLY:
Actually, you got the title wrong. If you are going to criticize, at least do it correctly. – moderator

Wondering Aloud

What is clear from the ice core data is two fold
1. Carbon dioxide trails temperature and so can not be the primary cause as it would violate causality.
2. The idea that temperature increase releases carbon dioxide is reasonable but the second part that this amplifies the signal is clearly not supported by the data in fact the shape and timings of the peaks and cooling portions of the graph falsify this hypothesis as well.
I see reason to think carbon dioxide should help warming however the ice core data really doesn’t support it.

Philip_B

It’s a mystery why we do not get runaway warming or cooling (to a stable state) in the glacial/interglacial cycles.
Something stops and then reverses the warming and cooling on a regular 100,000 year cycle. Although, the length of that cycle changed from about 50,000 years to a 100,000 years around a half million years ago.
Milankovic Cycles have been proposed as the cause, but several problems exist with this (proposed) cause.
http://en.wikipedia.org/wiki/Milankovitch_cycles#Problems
BTW, the CO2 as feedback theory is nonsense.
CO2 declines approximately linearly over the glacial phase of the cycle of about 80,000 years. And similarly it increases approximately linearly over the interglacial. This means CO2 will act as a negative forcing for about half of the time and most crucially for the first half of the glacial/interglacial period (when the two are averaged together).
So rather than being a positive feedback, CO2 is forcing the temperature in the opposite direction to whatever is causing the warming and cooling glacial cycle for the first half of the cycle.
In fact, if one were to ignore (the rather flimsy) evidence that increased CO2 causes warming and decreased CO2 causes cooling, CO2 looks to be a good candidate for driving the glacial cycle. Increasing CO2 progressively cools the climate, eventually overwhelming other positive feedbacks. Ditto for warming.

Nick Stokes

Steven
Yes, it’s a serious question. Gore showed the plot, as many have done. His main point was that CO2 is now at a higher level than it was during that period. I don’t see anywhere where he said (let alone insisted) that it drove glacial cycles.

Steven Goddard

It is quite amusing seeing AGW defenders scrambling to claim that “no one believes” CO2 is the driver. It was the AGW camp who attempted to use the ice cores to prove their case, and now they are disavowing any knowledge.
Al Gore stood in front of the giant Vostok Graph in his movie and said “there is one relationship that is far more powerful than all the others and it is this. When there is more carbon dioxide, the temperature gets warmer, because it traps more heat from the sun inside. “
Has he issued a retraction to the hundreds of millions of people who saw the film and believe what he said?

Stephen Brown

According to the story at this link …
http://www.telegraph.co.uk/earth/environment/climatechange/4734859/Scientists-capture-dramatic-footage-of–Arctic-glaciers-melting-in-hours.html
… we don’t have to worry as the glaciers have just about disappeared already.
REPLY: The title of that video is: ” Scientists capture dramatic footage of Arctic glaciers melting in hours”
I watched the video to the end. What utter unmitigated rubbish. First it was shot and edited like a TV reality show. Second there was no before and after proof in the video imagery showing “a” glacier let alone “glaciers” melting in entirety within a hours, or even days. It’s nothing more than video showing something that happens regularly on glaciers and icefields with seasonal changes. They melt, water runs under them to the base. It is called a “moulin”. Unfortunately many will be drawn in by the slick editing and the danger faced by the intrepid scientists dangling over the abyss. Oh the danger, what brave scientists! Except, other than take a water speed measurement, there was no science in that video, just antics for the camera.
A moulin is nothing new. Admiral (then Lieutenant ) Peary reported on it back in 1897 in the Journal of Geology. Read here.
– Anthony

Steven Goddard

Molon,
You are technically correct about the use of the term “negative feedback” but most people associate the term “negative feedback” with feedbacks which drive temperatures downward, and associate the term “positive feedback” with feedback that drives temperatures upwards.
I don’t see anyone disputing the logic of the article – so can I take it that the AGW camp agrees that Al Gore’s film was misleading?
.

Nick Stokes

Steven,
If you want to establish your point, you only need to name those who believe that, and quote what they say. Your quote from Gore is just a standard, if a bit oversimplified, statement of the greenhouse effect. It’s not saying CO2 drives glacial cycles.

Policyguy

Steven,
Well done.
I’ve observed over the last several years that very few day-to-day climate change believers, whether strident AGW alarmists or just every day citizens who read papers and watch TV, have any comprehension of the real scientific issues that come into play in a discussion of what climate change is, has been or could be. One of my policy friends questioned me the other day whether we had ANY data, before satellites, to support contentions of medieval warming, the mini ice age or solar cycles going back 250 years. Another penned an email asking whether it was true that its getting cooler, not warmer, and what proof exists. Apparently this person had been exposed to someone who indicated that predicted higher temperatures were not occurring. These are highly educated people who populate high corporate and government public positions responsible for implementing climate change policies, who don’t have a clue about what constitutes climate change. These are people who accept a public consensus that climate change will lead to a host of unimaginably horrible things related to an ever warming planet caused by human waste and avarice, They don’t yet realize that the current CC movement is fueled by a global political – economic ideology, not scientific concern. Its amazing, but our entire national public policy apparatus is now focused on saving us from supposedly increasing global temperatures when our true public policy risk is abrupt cooling and the utter havoc that will cause.
Your post is aimed at scientifically minded individuals familiar with glacial and interglacial cycles. I love it. Though I’m tempted to share your observations (and questions) with the people I cited above, to help educate them regarding the utter lack of scientific justification for our current craze, I hesitate because my fellow day-to-day climate change policy executives have no background to appreciate your observations and the implication of your logic. They have no conception that the IPCC reports are based on a “what if” premise of CO2 causation, rather than a scientifically based conclusion to a legitimate question about what was responsible for late 20th century warming.
So, I take my hat off to you for your clearly written and well thought out post. But I offer the observation that those who understand your work are either part of the choir or, if not, understand that the well educated policy executives in high corporate and public policy positions responsible for implementing new climate change policies have no way to process this information and will not be affected by it. Over the last several years I have identified only three or four individuals, out of the many who populate high corporate and government policy positions, who could appreciate your work. How sad.

Steven Goddard

Nick,
Al Gore’s claim is incorrect “there is one relationship that is far more powerful than all the others and it is this. When there is more carbon dioxide, the temperature gets warmer”
The Vostok data (which he was standing in front of at the time) disproves his point. 120,000 years ago, CO2 levels were high and temperatures were cooling rapidly. 14,000 years ago, CO2 levels were low and temperatures were increasing rapidly.
The Vostok data shows unequivocally that you can not make any prediction about the direction which temperatures are moving, based solely on the amount of CO2 in the atmosphere. Al Gore was wrong and has misled hundreds of millions of people. Still, he gets invited to give keynote speeches at AAAS.
And let us not forget that during the Ordovician, CO2 levels were 10X current values, and earth had an ice age.

Nick Stokes, the reasonable face of AGW pedantry; it is disingenuous to claim that a lack of CO2 doesn’t cause the ice-ages when AGW is premised on the hypothesis/fairy-tale that CO2 increases cause the opposite of the ice-ages; Arrhenius, who certainly thought a lack of CO2 would ice things up, is quoted with approval in Weart’s classic dystopic piece, “A Saturated Gassy Argument”;
http://www.realclimate.org/index.php/archives/2007/06/a-saturated-gassy-argument/
Keep trying Nick, you may stumble onto something consistent in AGW eventually, even if it is the R2 correlation between CO2 increase and Gore’s increasing wealth.

Steven Goddard

Now let us focus on the other half of Al Gore’s statement.
there is one relationship that is far more powerful than all the others and it is this. When there is more carbon dioxide, the temperature gets warmer
The Vostok data again proves that is incorrect. The most powerful driver has to be something else besides CO2, because whatever is driving the glacial cycles has to overcome and reverse CO2 feedback, as well as H2O, albedo and other feedbacks – all of which are working against a reversal.
Whatever drives glacial cycles must be a very strong force, and it is not CO2.

Brendan H

Steven: “There are still people who insist that changes in CO2 can explain the pattern of glacial and interglacial periods.”
This sentence is badly worded. It appears to be claiming that some people regard CO2 as the sole or primary driver of both glacial and interglacial periods.
It’s not clear who these “people” are, but the standard understanding of the change from a glacial to an interglacial period is that CO2 acts as feedback to a process – perhaps a change in the earth’s orbit — that sets off the initial warming that occurs at the end of an ice age.
http://www.realclimate.org/index.php/archives/2007/04/the-lag-between-temp-and-co2/langswitch_lang/in
If you are arguing that CO2 was not the primary driver of past glacial/interglacial cycles, then you are in agreement with standard AGW theory. The difference between the glacial/interglacial periods and now are:
1) We are not currently emerging from an ice age, and;
2) CO2 is now considered to be acting as a forcing, not a feedback.

Nick Stokes

Steven,
Gore did precede the quote you’ve given with the caveat “The relationship is very complicated.” And he went on to make a point that, in the context, was overly simplistic. But this falls a long way short of demonstrating your claim that: :There are still people who insist that changes in CO2 can explain the pattern of glacial and interglacial periods.”
Mike Ramsay pointed to a 2000 Science article which does come close to making that claim. Although that is not so long ago, the author clearly was not aware of data showing the phase sequence of heating and CO2 rise – his claim is that both preceded ice volume changes. The IPCC AR3 in 2001 did say that CO2 lagged temperature, which pretty much settled this issue.

Wondering Aloud

You may want to check on what Leif has been saying on various threads here. His field is solar astronomy and he seems to be able to argue convincingly that solar variability doesn’t match the record either.
It isn’t that we know why the climate is varying, I am just darn tired of being told that we do. Things like “an inconvenient truth” do significant harm to science as a whole and as a result to society.

Ozzie John

Hi Nick,
Maybe you could add your thoughts on what does drive the Glacial Cycles to support your viewpoint. If you don’t believe it’s CO2 then you would be more aligned with Steve’s post than with the AGW camp !

CO2 is a trace gas, the Atmospheric (incorrectly coined Greenhouse) Effect is not about infared this or that or insulation. It is about boundaries of convective zones (mass) of fluid. AGW violates what we understand of thermodynamics.
How the physics of this whole area of study was supplanted with politics is a ‘case study’ in a sociology class.
Whether that is science or not is another debate.
As far as interglacials and glaciations go … how many people out there understand that we are at the end of an interglacial in what could be called a long ‘ice age’ and it could end at any time like it did many times in the Vostok record. My guess is we have a millenium before the Milankovitch cycle takes over. Not very long considering it took us this whole interglacial for mankind to start hitting his stride. We will need a few centuries like the 20th, in terms of technological development, to deal with evacuating most of North America, Europe, and Northern Asia. Evacuate may be the operative term given that some evidence, even this graph, indicates the onset can be very quick … even a decade. Now that would be a good ‘what if’ for a sociology class.

One need to be cautious with drivers and feedbacks…
Theoretically, there is a positive feedback of CO2 on temperature, as good as ice sheets and vegetation albedo changes are positive feedbacks on some inititial temperature change. To avoid any confusion: a positive feedback strengthens the initial change in the same direction, be it up or down.
Does that mean that a positive feedback always lead to a runaway process? That depends of the feedback factor: As long as the feedback effect is smaller than the original forcing (feedback factor smaller than one), there is no runaway, but only a higher response than from the original cause alone.
Is there a positive feedback of CO2 on temperature measured in the Vostok (or other) ice core(s)? No. Even a 40 ppmv drop at the end of the Eemian (the previous warmer (than current) period doesn’t show a measurable decrease of temperature, while a 3°C/2xCO2 should cause a drop of 0.5°C, according to current models:
http://www.ferdinand-engelbeen.be/klimaat/eemian.html
Temperatures (and methane) are already at minimum and ice sheets again at maximum when CO2 starts to drop, without measurable effect on temperature.
The same is true for the warming from the LGM to the Holocene: There is a clear influence of temperature on CO2 levels, but no measurable influence of CO2 on temperature, as one should expect if CO2 is an important feedback:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/epica5.gif
With thanks to André van den Berg, who provided the graph.
Thus all together, the least one can say is that even if CO2 forms a positive feedback, that is not measurable in the ice cores and far overblown in current GCM’s…

I see no reason to single out Al Gore or even James Hansen. A vast army of people believe that CO2 forces global temperature increases. The CO2 Believers are planning “the largest mass civil disobedience for the climate in U.S. history” on March 2 in Washington DC. The Obama Administration is thick with such folks. It’s hard to find any politician that doubts that CO2 drives global temperature.
And yet the ice record clearly shows that CO2 does not force global temps up or down. Temps fell when CO2 was high, and rose when CO2 was low, and vice versa. That factoid has been demonstrated numerously at WUWT (my personal favorite was the post by Frank Lansner last month).
http://wattsupwiththat.com/2009/01/30/co2-temperatures-and-ice-ages/
I know it flies in the face of The Consensus, but increased CO2 over the last ten years has been accompanied by falling global temperatures. Ipso facto, that theory is wrong. The ice record confirms that CO2 as the climate forcing GHG is bunkum, and in fact throws the entire GHG as a forcer of climate change into question, regardless of whichever GHG we’re talking about.
It does no good, I know, to tell True Believers that the seas are NOT going to boil. Some folks are deeply invested emotionally as well as financially into the End of Creation hysteria. But I tell them anyway, not to bum their trip but out of a slim hope that logic will cure their madness.

tty

A few notes on the previous interglacial 120,000 years ago:
The CO2 level was actually a bit higher than 290 ppm see:
http://www.geol.lu.se/personal/MSR/bjerknes.pdf or:
http://www.geol.lu.se/PERSONAL/DNH/images/RUN2005.pdf
The ice-core record smooths out the short-term changes during the interglacials, and is probably systematically low at least during interglacials (stomatal index measurement give consistently higher results during the Holocene too) .
The temperatures in northern Siberia were MUCH higher than today (on the order of 10 degrees centigrade) and forest extented to the Arctic coast, but no noticeable CH4 release resulted, nor did it during earlier warm interglacials. This strongly suggests that this particular feedback is imaginary.
About the Ordovician glaciation. Not only did it occur at a time of much higher CO2 levels, it may well have been the most severe during the Cenozoic. It is the only glaciation to have caused a mass extinction.

John Edmondson

Also the cyclicity of glacial/interglacial is a crucial point. The ice ages are driven by 3 interacting astronomical variables.
1.These are the variation of the earth’s orbital eccentricity. The eccentricity varies between 0 , a perfect circle, and 0.1, at these times the earth sun distance varies between 88 and 98 million miles. Cycle length = 100,000 years
2. Axial inclination , this is currently 23.5 degrees, but can vary between 22.5 and 24.5, cycle length = 41,000 years.
3. Precession of the equinox, this is the variation of the seasons compared with the calender. i.e. in the NH summer solstice occurs in June, but in 13,250 years time NH summer solstice occurs in December. Cycle length = 26,500 years.
An Ice age will happen when the above parameters cause reduced solar heating in the NH summer. Permanenet Snow and Ice moves south , increasing the earth’s albedo. This positive feedback continues to reduce temperature until the ice covers all of Canada, the Northern part of USA large parts of Europe. Typically the average temperature is 5 degrees below what we see today.
Ice ages are a lot easier to start than to end. The is why glacial/interglacial times spans are typically 100,000/20,000 years.
To end an Ice age the sun would have to a maximum heating effect to melt the Ice and reduce the albedo. To do this the axial inclination would have to be near 24.5 degrees, NH summer solstice sun distance near to the minimum of 88 million miles.
2 other points.
Ice ages are a NH only, antartica has little or no influence on this.
Carbon dioxide varies during Ice ages, but is not the driver.

foinavon

Mike Ramsey (22:34:44)
Your selective quoting of a sigle sentence of Shackleton (2002) misrepresents the theme of the article. Shackleton and the science of 2000 in general recognised the dominant role of Milankovitch cycles as the primary drivers of ice age glacial-interglacial cycles. The question was what factor(s) amplify the rather puny changes arising from variations in insolation due to changes in orbital eccentricity.
A previous study (Imbrie) had proposed that the temporally primary amplification was ice sheet dynamics (albedo feedbacks). Shackleton (the paper you linked to) analyzed deep sea sediments and the new glacial core records to infer a phasing of drivers (Milankovitch orbital eccentricity) and amplifiers (CO2; ice sheet albedo responses) and concluded that the primary amplifier of the weak orbital eccentricity was CO2 rises in advance of albedo effects through ice sheet dynamics.
So Shackleton (2000) can’t really be “recruited” to support the straw man “argument” of the top post. Then as now, the evidence supports CO2 and albedo effects as the primary amplifiers of the orbital variations that drive the ice age cycles (we’d probably reinstate ice age dynamics a little more prominently nowadays since we have a better handle on the relative timings of responses now).
Nicholas J. Shackleton (2000) The 100,000-Year Ice-Age Cycle Identified and Found to Lag Temperature, Carbon Dioxide, and Orbital Eccentricity Science 289, 1897 – 1902

Wondering Aloud

How strong is the evidence that the orbital cycles people keep mentioning are in fact the cause of the glacial cycles? I only ask this because until a few months ago I was convinced they could, now… not so much. We need an explanation for the glaciations ending is the problem, if we haven’t got that we haven’t got much.

mugwump

Steven Goddard,
How can you be so simplistic as to take Al Gore’s claims on face value?
“there is one relationship that is far more powerful than all the others and it is this. When there is more carbon dioxide, the temperature gets warmer”
Clearly, what Al meant depends upon what the meaning of the word “is” is.
[/sarc]

Roy

Molon was absolutely right about the negative/positive feedback distinction, and if anyone is going to use that term they should either use it properly or make it explicit that they using it colloquially (i.e. wrongly).
It’s not a mistake I would make and I immediately tune out when I see someone else making it. It is a big deal–almost worth blogging about.

E.M.Smith

Bill D (22:35:08) : All of the science that I have read says that sun cyles drive the long term glacial cycles
I assume you meant to say ‘insolation cycles due to orbital mechanics’ since solar cycles don’t have any known 100,000 or 40,000 year periodicities…
Warming increases rates of bacterial degredation on land and in water, as well as making stronger thermal statification in the oceans. Thus, warming can lead to less CO2 burial in the ocean and more CO2 release from soils. Right now the tundra is a major reservoir of organic carbon. If warming and melting continue, releases from this source will increase.
And what about the effect of growing 25 to 50 TONS per acre per year of plants (as demonstrated in Eucalyptus, Willow, and Poplar groves)? Hmm? How about that 40% increase in growth rate demonstrated from higher CO2 levels?
Please balance your CO2 books on plant dynamics. Warmer and higher CO2 results in much greater biosequestration over most of the earth surface. Look beyond the tundra…
Yes, this matters a great deal. Just where do you think all that coal and oil came from in the first place… See peat bogs for a modern example of the process still at work.

Ellie in Belfast

The one question we need to ask is this –
“Can the climate get COOLER when there are high(er) levels of CO2 in the atmosphere?”
This needs to be asked – and answered – clearly, loudly and often. The answer, clearly and unequivocally, from historical data, is YES.

Allen63

I question if the historic interglacial CO2 peaks were in the 290 range (as on the graph). The ancient atmospheric CO2 has not been directly measured. Rather, ice core measurements have been “adjusted” by a “factor”. I question the “factor”.
Could be that current CO2 levels are not any higher than recent ancient interglacial levels. A bit OT for this thread, but it is something I think about every time I see that graph.

So, here I am lurking around, not being particularly scientifically minded (leaning toward Psychology rather than a hard science because that’s just how my mind works) and I see statements like Nicks, and wonder…
You see, the last 20 years of the AGW hype have been premised on the idea that CO2 drives the climate. To state, now, that this has never been stated in the precisely worded way Nick asks for is rather like turning to a large haystack and saying “But there isn’t a straw in there that’s exactly 111.762 mm with a diameter of 16 mm, therefore the entire haystack doesn’t exist”.
It’s a clever bit of obfuscation to say that nobody has made a precise statement but it rather misses the point; the claim has been that CO2 drives climate. The proof is lacking, and the claim falsified by the data.
Back to lurking!

John Philip

We look forward to Mr Goddard’s next post where, having single-handedly shown how the world’s assembled climate and coral experts are mistaken he goes on to demonstrate that chickens cannot actually lay eggs because the chickens ‘lag’ the eggs… 🙂
The same argument was advanced by Viscount Monckton, and the counterargument elegantly expressed by Dr Stephan Harrison, Senior Lecturer in Physical Geography at the University of Exeter
He says that during glacial/interglacial transitions, increases in atmospheric C02 follow rather than precede warming, and argues that this nullifies the present causal link between high levels of CO2 and observed warming. Of course it doesn’t. Warming at glacial/interglacial timescales is driven by orbital forcing, with C02 playing an important feedback on global temperatures. This is entirely different to the situation that exists today, where changes in insolation amounts or patterns are insufficient to explain the warming we see. Either Monckton knows this (in which case his arguments should be dismissed as pure propaganda) or he doesn’t know this, in which case his understanding of the science is woeful.
Are we getting hung up on semantics here? Historically CO2 does not ‘drive’ the changes in temperature, in the sense of initiating them, but does act as a powerful feedback once they are underway, which explains the ‘lag’. Not a difficult concept really.
Others adressing the issue include the Royal Society see misleading argument No 3,, RealClimate, (read the letter by Professor og Geosciences Jeff Severinghaus) its a New Scientist Climate Myth, and it is currently No 11 in the skeptical science list of arguments.
Reply: Tone it down ~ charles the moderator

nevket240

“We look forward to Mr Goddard’s next post where, having single-handedly shown how the world’s assembled climate and coral experts are mistaken”
Oh, really sir. Assembled where?? How many are feeding on the public teat?? How many are really Climate Scientists??
or just politically appointed advocates who are not being held accountable?? Why are so many other Climate Specialists now forging a publicly visible rebuttal?? Do you regard political activists hijacking public policy through bad science to be a moral issue or a “feedback” of some sort.
regards

foinavon

Steven Goddard (00:06:50)
It’s worth putting back Gore’s previous sentence from that part of his film you quoted from:
The relationship is very complicated. But there is one relationship that is more powerful than all the others and it is this. When there is more carbon dioxide, the temperature gets warmer, because it traps more heat from the sun inside.
Of course it would have been better if Gore had said “all else being equal, when there is more carbon dioxide, the temperature gets warmer….”. That would accord with scientific understanding. In any case I suspect that everyone that is interested in this subject will know that orbital variations “drive” the ice age cycles and are amplified by CO2/albedo (and water vapour!) feedbacks.
A more serious point is your assertion:

And let us not forget that during the Ordovician, CO2 levels were 10X current values, and earth had an ice age.

That’s rather “Gore-like” in its omissions! First it’s incorrect since we simply don’t know what the CO2 levels were at the time of the late-Ordovician glaciation nearly 450 million years ago.Unfortunately we don’t have any paleoCO2 proxies contemporaneous with that event. Secondly it’s very well characterised that the solar constant was around 5% weaker then (late-Ordovician) than now, and so the threshold for significant glaciation was much higher then than now. So whereas widespread glaciation can occur on Earth now with CO2 levels around/below 500/600-ish ppm of CO2, during the late-Ordovician greenhouse gas levels would have to be much higher (greater than 2000 ppm and perhaps as high as 3500 ppm CO2 [***]) to suppress significant glaciation.
e.g. D. L. Royer (2006) CO2-forced climate thresholds during the Phanerozoic Geochimica et Cosmochimica Acta 70, 5665–5675

Syl

“So whereas widespread glaciation can occur on Earth now with CO2 levels around/below 500/600-ish ppm of CO2…”
then why-o-why are people so adamant we have to get back to 280 or so and that the 380 we currently have is close to or beyond a ‘tipping point’? We are currently STARVED of co2 and 280 is dangerously low for the health of life as we go into the next glaciation. I have seen NO studies that quantify the loss of life as CO2 was depleted from the atmosphere as the globe cooled. All scientists have been interested in is extinctions! Well, if a few individuals of a species survive and therefore don’t go extinct that doesn’t make killing off most of them due to co2 starvation okay does it?
This makes the one-sided arguments of warmers rather specious and empty.

Wondering Aloud

The problem is the relationship that is “more powerful than alln the others” is also clearly dead wrong from the vary data set he is pointing at.
Claiming minor problems with what someone else says does not alter this HUGE deliberate falsehood.
Why are paleo proxies OK for the AGW folks to abuse but not ok when the evidence in them disputes it?

Nick Stokes

Roy and Molon: I absolutely agree – proper use of the term negative feedback is important.
On feedback Ferdinand gives a good summary too, until it comes to GCM’s and modern times. Now CO2 is not a feedback – it’s a forcing. We’re injecting it into the atmosphere.
Ozzie John and cohenite – foiunavon above has summarised the standard theory of Ice Ages. AGW theory doesn’t say that past warmings were caused by CO2, and I don’t believe they were. It just says that the present unique circumstances, in which large amounts of fossil carbon are being added to the atmosphere, will cause warming.
In fact CO2 change was never a good explainer of Ice Ages. It would only raise the question – what drives the CO2 change (then)?

gary gulrud

“Now CO2 is not a feedback – it’s a forcing.”
All right, a feedback in AGW-speak changes the amplitude, got it. So one can’t model more than quadratic functions? Seems that a forcing could go negative in non-linear systems.

M White
Philip Mulholland

A Centifugal governor is a mechanical device that automatically determines the power output of a steam engine and is an example of system control via negative feedback http://en.wikipedia.org/wiki/Centrifugal_governor
The phrase “Dangerous negative feedback” is an oxymoron with a dissemblance rating of genius level.

John PhiliP quotes:

…the situation that exists today, where changes in insolation amounts or patterns are insufficient to explain the warming we see.

What warming?
CO2 is a minor forcing agent, overwhelmed by other factors. Our planet is proving it to those who simply open their eyes: click

David Porter

Nick Stokes (03:41:51) :
“In fact CO2 change was never a good explainer of Ice Ages. It would only raise the question – what drives the CO2 change (then)? ”
How about temperature?

David Porter

John Philip (03:24:53) :
Are we getting hung up on semantics here? Historically CO2 does not ‘drive’ the changes in temperature, in the sense of initiating them, but does act as a powerful feedback once they are underway, which explains the ‘lag’. Not a difficult concept really.
Explain the concept please because I find it difficult. The difficulty I have is that I feel I have to believe it before I can understand it. Would that be correct?

Nick Stokes

David Porter
How about temperature? Well, it’s temperature that you’d be trying to explain, so that won’t do. Although it’s not too far off – heat vaporising CO2 which causes heating … is the kind of positive feedback mechanism which can promote oscillation from relatively weak drivers. But you still need a driver – orbital aberrations have the right kind of frequency.
I think the role of CO2 in this kind of feedback should not be overstated – water vapor is probably more significant.

DocMartyn

” Bill D (22:35:08) :
Thus, warming can lead to less CO2 burial in the ocean and more CO2 release from soils.”
O.K., on the last point; where and when did the carbon become entrapped in the soil?
Organic material is sequestrated in the soil during growth, are you suggesting that during a cold period there is more entrapped, which is released when things heat up?
Can you model the time-line for the entrapment of carbon and its release on the same time scale as presented by the author.

mugwump

John Philip (03:24:53) :

Historically CO2 does not ‘drive’ the changes in temperature, in the sense of initiating them, but does act as a powerful feedback once they are underway, which explains the ‘lag’. Not a difficult concept really.

The whole point John is that the “powerful feedback” part is entirely unproven. The Stefan-Boltzmann law gives a very weak feedback effect of about 1 degree for doubling of CO2. Anything beyond that requires invoking even more powerful feedbacks such as water vapor, and discounting potential negative feedbacks such as clouds.
Steven’s post illustrates this nicely: if CO2 was such a powerful feedback then how come the ice core record shows that it seems to be almost completely overwhelmed by other effects?
The simple fact is we still have very little understanding of the relative strengths of the different feedbacks and how they are influenced by the climate state, despite Al Gore’s and the alarmist industry’s vociferous claims to the contrary.

Dorlomin

Steve Goddard has excelled himself again. Posts like this will have all those so called ‘scientists’ quaking in their boots!

Alexander Harvey

Here is a longer Benthic Carbonate reconstruction:
http://en.wikipedia.org/wiki/File:Five_Myr_Climate_Change.png
Visually I notice the appearance of greater variance or amplitude with lower tempertures.
Is this real or an artifact of the reconstruction? Anyone know?
If it is not an artifact then does it imply that the climate is more stable when temperatures are warmer? (Less positive feedback?)
If so, does that imply Climate Sensitivity has declined with increasing temperatures?
These are not statements, just questions; as I sure do not know. If it is an artifact it needs sorting as it is very suggestive of a real difference in the temperature stability between warm and cold periods.
Alexander Harvey

Tim L

Looks like a place to post this, note 100,000 years pattern in graft.
The Fermi telescope and NASA’s Swift satellite detect “in the order of 1,000 gamma-ray bursts a year, or a burst every 100,000 years in a given galaxy,”
http://news.yahoo.com/s/afp/20090219/sc_afp/sciencespaceastronomy;_ylt=AgMlEZoKo9cB4K9JUXloNxVxieAA;_ylu=X3oDMTE5djBmdHJiBHBvcwMzBHNlYwN5bi1tb3N0LXZpZXdlZARzbGsDaHVnZWdhbW1hLXJh

Bill Illis

For the opposite point of view on CO2 and the ice ages …
You have to read Hansen’s latest paper published recently in Open (Access) Atmosphere Science Journal (but was rejected by Science and even NASA would not put out a news release on it)).
The long list of coauthors includes all the paleoCO2 experts.
He is bumping up the long-term equilbrium warming estimate to +6.0C for a doubled CO2 based on his current understanding of how the ice ages work, the now-slower-than-thought ocean thermal response time, the causes of the Antarctic glaciation (now I know why foinavon keeps bringing this up) and the Eocene thermal maximum.
Here is the full paper.
http://www.columbia.edu/~jeh1/2008/TargetCO2_20080407.pdf
The published one is here (just small changes and authors added).
http://arxiv.org/abs/0804.1126
Basically, warming will be slower than originally thought, but most of the ice sheets will still melt and the albedo feedback from the lack of ice will push us to +6.0C from a doubled CO2 within 1,500 years.
This all depends on his current understanding of how the ice works and his misunderstanding of Pangani’s CO2 estimates during the Antarctic glaciation.

nevket240

“Basically, warming will be slower than originally thought, but most of the ice sheets will still melt and the albedo feedback from the lack of ice will push us to +6.0C from a doubled CO2 within 1,500 years.”
1500 years.??????? good grief!! this looks like a “get out”
Look back 1500 years and see how far humanity has come technologically. Just look back 100 years !!
The EcoDruids are in panic mode as shown by the Steig Affair
and that noteworthy attempt to involve the last man standing in this sordid affair of AGW, Antartica.
regards

redneck

tty (01:45:59)
The Ordovician occured during the Palaeozoic era.
M White (03:50:08) :
“Wrapping Greenland in reflective blankets”
I wonder if academics, like Dr. Box, ever think about the practical aspects of their proposals. It does explain why academics, like Dr. Box, should remain in institutions and not venture into the private sector.

Steven Goddard

What the Vostok cores show is that there is 0% correlation between CO2 levels and the direction the temperature is moving. You can pick any CO2 level on the graph, and find an equal number of points where the temperature is going up, and where it is going down. This is the exact opposite of what Al Gore was claiming.
As far as Dr. Hansen goes, he put this claim in his Illinois Wesleyan presentation.
Chief instigator of climate change was earth orbital change, a very weak forcing.
http://www.columbia.edu/~jeh1/2008/illwesleyan_20080219.pdf
This claim is self-contradictory. The “chief instigator” would have to be the strongest influence in the system, because it has to be able to overcome the combination of all of the other feedbacks in order to reverse the direction which the temperature is moving. 15,000 years ago CO2 was low, H20 was low, and albedo was high – yet the temperature started rising quickly. Changes in the earth’s orbit had to be able to overwhelm the combination of CO2 forcing + H2O forcing + albedo forcing, all of which were working to lower temperature further at the time.

Steven Goddard

I taught a class of 10 year olds on Friday. The class was not about global warming, but one of the children raised the subject.
If you want the names of people who believe that Al Gore’s giant CO2 graph proves that rising CO2 leads to rising temperatures, go to any public school and talk to the brightest children. They all have been brainwashed to believe this.
Whether or not AGW is a serious concern, the Vostok graph tells us nothing about it. All that it shows is that there is a relationship between temperature and CO2 levels.

Steven Goddard

For clarity, I asked Anthony to add the following addendum to the article, but I don’t know if he is busy with CA today.
The use of the term “negative feedback” in this article is the commonly understood meaning – i.e. feedbacks that drive temperature down. Technically speaking, this usage is incorrect. From a viewpoint of semantics, a negative feedback would be one that works against the current trend. This semantic difference has no relevance to the logic being presented in the article.