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CO2 vs temperature: ice core correlation & lag


The temperatures and carbon dioxide concentrations have been correlated - see e.g. Petit et al., Nature 1999 - but we know for sure that the temperature was the cause and the concentration was its consequence, not the other way around. This fact has also been explained in The Great Global Warming Swindle. It follows that the C0₂ greenhouse effect has not been important in the history and we shouldn't expect that it will become important in the future.

Special comment for Australian readers on Sep 28, 2007: just yesterday, there was a new paper in Science - Lowell et al., Science 2007 - that showed that CO₂ lagged by about 1,000 years when the last ice age started to end 18,000 years ago
The direction of the causal relationship can be shown in many ways: for example, it is not just CO₂ but other gases such as methane that follow temperature. The hypothesis of CO₂ as the primary reason wouldn't explain why these other gases are correlated, too. Also, we understand how oceans react to temperature changes by releasing gases. Finally, the gas concentrations lag behind the temperature by 800 years, see e.g. this 2003 paper in Science by Caillon et al.

Main text

The movie of the former future U.S. president - "An Inconvenient Truth" - has impressed many viewers: it is an optimized promotion of the alarmist understanding of the global climate. Moreover, it shows a more attractive Al Gore than the old Al Gore whom we know from the 2000 campaign.

A few years ago, Gore visited Harvard and with Jochen Brocks, my fellow Fellow, we went to see him. Jochen is a leftist, of course, but he claimed that Gore looked repulsive, unhuman, and evil. I am a rightist but paradoxically, I never had terribly serious complaints about Gore's looks.

Don't get me wrong: I certainly think that George Bush is more human and looks like a more trustworthy and more human being than Al Gore, and I wish him the best on his 60th birthday! Nevertheless, their design is not the primary thing that determines my political and scientific opinions.

That's why I am going to discuss more important issues, namely the scientific ones. The most powerful argument in Al Gore's movie were the graphs showing the correlation between the carbon dioxide concentrations and the temperature extracted from ice data in the last 650,000 years.

Figure 1: Correlations between the temperature and the concentrations extracted from the ice cores (click to zoom in). Combined graph by Thomas Stocker of University of Bern, Switzerland

(Incidentally, if you care, the concentration of CO2 and CH4 is determined by a direct chemical analysis of the bubbles. The temperature is reconstructed from the concentration of frozen heavy water - water with the one normal hydrogen atom H replaced by the heavy hydrogen D, known as the deuterium - in the same bubbles. Why? Because the warmer weather there was, the easier it was for heavy water vapor molecules to get to a sufficient altitude - think about the Maxwell-Boltzmann distribution - and to join clouds whose precipitation was adding ice to the ice sheet during the same year.)

No doubt, the correlation between the temperature and CO₂ is nearly perfect. No doubt, the climate on the Earth in the 650,000 years before the industrial revolution can be described very accurately by a single function of time. But if two things, A and B, are correlated, does it imply a particular causal relationship?

In classical physics, the answer is essentially Yes. The perfect correlation must either mean that A is caused by B, or B is caused by A, or both A and B are caused by something else, namely D. It is completely clear what is Al Gore's answer: the temperature was determined by the concentrations of carbon dioxide. That's why all of us are going to die in a hell by The Independence Day 2016 unless all of us accept Al Gore as the ultimate savior, neglecting that he is not a Christ but rather an anti-Christ as Rae Ann has noticed. ;-)

Figure 2: Climate scientists extract the ice cores.

According to Gore, the concentration of carbon dioxide from the ice core records (see the picture above) was evolving according to its free will and does not require any explanation. The concentration could have been caused by oil companies owned by various mammoths. At any rate, Al Gore does not have to answer why the carbon dioxide concentration was changing in the first place. He does not have to answer because he is the savior.

Now imagine that you have the freedom to think about these things rationally, as opposed to metareligious quasithinking under the influence of crazy brainwashing. First, let us try with the following exercise.

What is the cause and what is its effect

Imagine that you find out that whenever you smell methane in the living room, you can also find a certain person in the same room. The correlation is nearly perfect. What is the conclusion? Someone could propose that the methane in the room is the cause whose presence creates the person. I would propose an "alternative" explanation: it is the person who creates the methane whenever he is in the room. Choose any explanation you want.

I picked methane because it will play a role in the main example, too.

You should notice that the graph above shows a perfect correlation not only between the temperature (A) and the carbon dioxide concentration (B), but also between the temperature (A) and the methane concentration (C). What is the cause and what is the consequence if three quantities are correlated so nicely?

Note that the answer can't be unique a priori. At most one of the three quantities - A,B,C - can be the primary cause. Which one? Clearly, if you choose one of the gases, your explanation will be asymmetric and it won't explain all the correlations in a satisfactory way. If you say that the carbon dioxide concentration determines the temperature, you must still explain why the methane concentration (and other concentrations such as N2O, for that matter) follows the same time dependence. You will clearly need a different explanation. If the CO₂ greenhouse effect is primary, you can't explain why the concentrations of CO₂ and CH4 coincide. Unless you find another inevitable explanation of this subtlety, your theory will be very weak.

Actually, we have more than logical arguments of this kind. We know very well why the causal relation is the opposite one. Imagine that you have a small bottle with 385 milliliters of Coke. It originally contained 4 volumes of carbon dioxide: if you extract carbon dioxide from one bottle of Coke to empty bottles at normal conditions, you will fill four bottles. I had to learn these things when we discussed various thermodynamical issues with Brian Greene when he was writing his second excellent book. Now, imagine that the CO₂ has leaked a bit and there is only 1 volume of CO₂ left in the bottle.

Take this bottle to your car whose internal volume is 1 cube meter i.e. 1 million milliliters. The carbon dioxide from the Coke makes 385 ppm (parts per million) of the volume of your car - just like the ratio in the atmosphere.

Suddenly, you notice a strange correlation between the concentration and character of the bubbles in the bottle on one side, and the temperature in your car on the other side. You will have two possible interpretations. Either the leaking CO₂ in the Coke determines the temperature in your car because the Coke with more CO₂ is a bit darker for the Sun that is shining to your windows (or for the infrared rays reflected from the chairs), or the temperature in your car determines how the bubbles behave in the bottle. Which explanation do you choose? ;-)

I think that any sane person obviously chooses the temperature as the cause and the concentrations as a consequence. Everyone who has ever tried to open a bottle of lemonade during a hot day must know why. Hot liquids are not able to absorb gases so well. Warmer oceans are not able to absorb atmospheric gases either. Clearly, if the temperature goes up, less carbon dioxide and methane can be bound to the ocean waters, which is why their concentration in the atmosphere goes up: this process is known as outgassing.
See: Ocean carbon sink, outgassing, and Henry's law
This explanation obviously works both for CO₂ as well as CH4 and other gases that could appear such as N2O.

There are many other mechanisms that contribute to the correlation between the temperature and the concentrations. For example, the frequency of fires may increase when temperatures are warmer, and fires create more CO₂. Also, the growth of plants and animals (consumers and producers of CO₂) depends on temperatures - but the most important contributions to the correlation work in such a way that the temperature is primary and the concentrations are secondary. If you think for a while, you will realize that the example with the car is actually pretty much realistic and the ability of water to bind gases is much stronger an effect than the greenhouse effect.

Even if you did not believe that conclusion and preferred the Al Gore's explanation that methane and CO₂ create the person or the warming, you will have problems to predict the future. While the correlation between A,B,C was nearly perfect in the past, we have violated this perfect harmony because we produce CO₂ and CH4 at different rates. We can deliberately do so. You won't get any natural prediction for the temperature because the correlation data itself can't tell you how much the two gases contribute.

Figure 3: A map of the Vostok lake. The deeper you go, the further you get to the history because the ice was being added at the top. Different years look like different layers of ice, in analogy with tree rings.

You should better look at physics, and physics tells you quite clearly that the ability of water to bind gases is more important an effect for the correlation than the greenhouse effect, and this fact will influence the measurements from The Subglacial Lake Vostok System, a Russian center in Antarctica (see drawing above). The temperature is the primary cause of secondary quantities such as various concentrations - and I would expect advocates of a "global warming" theory to agree with me that the temperature should be the fundamental quantity. This description explains all the correlations and not just some of them.

Much like all other potential explanations, it still says nothing about the origin of the "primary" quantity, in this case temperature. If temperature is indeed the primary and fundamental quantity, why was it changing the way it did?

There are many contributions to the temperature variations we partially know - such as various periodic astronomical cycles or solar variation - and there are many others that we don't know well or we don't know at all - such as nonlinear chaotic effects in the formation of different kinds of clouds. But I think that even though we don't know some things for sure and in their entirety, we can still be pretty much sure that certain hypotheses are almost certainly incorrect. The hypothesis that the CO₂ concentration was primary and it determined the CH4 concentrations and the temperature is one of such extremely unlikely hypotheses.

And that's the memo. But let us add a cute and important point.

What does the 800-year lag mean

There exists a simpler way to show that the temperature was the cause and the carbon dioxide concentration was a consequence, not the other way around. If you look carefully at the graphs, you will see that the carbon dioxide concentrations lag behind the temperature by 800 years. There have been many papers that found and reported the lag. One of the newest and most accurate ones is this 2003 paper in Science by Caillon et al. (full text, click).

On the graph above (click to zoom in), the past is on the right side, time goes to the left. You can see that the Antarctic temperature starts to change first, and CO₂ responds with a 800-year lag. Methane is still correlated with both. The graph is not new. Today, we have many more accurate graphs of this kind, many of which are from more distant past. We also have a more detailed analysis by Stott et al. (Science 2007) of the end of the last ice age 19,000 years ago where CO₂ lagged by about 1,000 years, too.

The explanation is obvious: oceans are large and it simply takes centuries for them to warm up or cool down before they release or absorb gases.

The work proving the lag was recently explained in Scientific American as well as RealClimate where they also essentially claim that you can easily produce a time machine as long as you want to travel only 800 years - or anything less than 5,000 years - to your past. ;-)
See also: CO₂ lag and how alarmists think
I leave it up to you whether you learn just the hard data or also their bizarre interpretation, and whether you will think that the RealClimate people are sane according to this interpretation. I personally don't think so. They would be right if they said that 90% of the time, the temperature and gas concentrations move together, and if you could hide the remaining 10% of the data, you couldn't learn the direction of the causal relationship.

But scientists who don't want to close their eyes can look at these critical 10% of the data, too. The result of such an analysis is that the impact of temperatures on gas concentrations is much stronger than the opposite influences, including the greenhouse effect. This fact can be extracted from the time periods where the trend is changing but because the physical laws themselves don't change, it is very clear that in the remaining periods, it is still true that the influence of temperature on the gases is stronger than the opposite influence. The only way to hide this conclusion is censorship, witch hunts, and burning of heretics at stake. There is no scientific way to deny this clear conclusion from the data.

The comments in some of these articles that the greenhouse effect could still be important is just fog that the authors included in order for their "politically incorrect" scientific conclusions to get published. This fog was probably incorporated into these papers by reviewers-alarmists, but this fog makes no sense whatsoever.

It follows from an analysis of the data that the greenhouse effect couldn't have been too important at the multi-millenium timescale.

Appendix: Gore's lift

If you have seen Al Gore's movie, you may also remember the lift. He argued that because there has been a correlation between CO2 and the temperature during the glaciation cycles, the significant recent growth of CO2 may be directly translated to a huge warming.

But we already know that this prediction is falsified, either by understanding the opposite direction of the causal relationship, as explained above, or simply by looking at the basic numbers:

During the ice ages, the concentration was 180 ppm (parts per million) and it grew to 280 ppm or so during the (warm) interglacials. This increase by 100 ppm of CO2 was accompanied by 8 °C of warming or so. But the same increase of CO2 from 280 ppm in 1800 to 380 ppm in 2005 was only accompanied by the measured 0.7 °C warming or so (even if we assume that all of the observed warming is man-made), more than one order of magnitude smaller than 8 °C. We simply know that the warming caused by CO2 is at least 10 times smaller than Al Gore tries to suggest with his exercise.

Incidentally, if you care, after many centuries or a few millenia, the correlation between CO2 and the temperature will get restored again. But the details how it will happen are inconvenient, too: in a few centuries after we stop adding CO2 to the atmosphere, the oceans will absorb or "suck" most of the "excessive" CO2. Therefore, they will also undo the small warming by 1 °C or so that the excessive CO2 has caused. The oceans have a huge capacity.

Other likable climate articles on The Reference Frame

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reader Charles Jordan said...

I was just starting to do the same thing on global warming. You mentioned the effect of cosmic rays on the cloudiness of the atmosphere. There is an anticorrelation with the sunspot activity which means that more sunspots means less cosmic rays which means less clouds on average. That mean more energy gets to the ground and the ground heats up - global warming. Warming causes CO2 rather than the other way around. Average sunspot activity has been going up and can account for most of the heating we see in the last 50 years.
Just as interesting is the analysis by Nir Shaviv and Geis and Helfel of the orbit of the sun and the earth through the galaxy. They compared the periodic passage through the spiral arms of the galaxy (high cosmic ray flux from supernova, etc.) with the major ice ages over the last 500 Myr and found very good correlation between the period and the present position (phase) of the effect. By the way the cosmic ray flux was also determined independently from meteorites to be high when the solar system is in an arm of the galaxy.
As you mention, this phase question is a big problem for the CO2 people because the temperature change happens before the CO2 change when it should be delayed if anything by the approx 100 years it takes for a the absorption of heat to cause a change in temperature.

reader jbg said...

"In other words, CO2 does not initiate the warmings, but acts as an amplifier once they are underway. "

From 318 ppm to 380 ppm in 50 years...

reader Luboš Motl said...

Dear jbg, you should distinguish science and religion. CO2 might act as an amplifier but there exists no experimental evidence that this fact is relevant at all.

The RealClimate.ORG people are neither trustworthy people nor independent neutral scientists and what they write about this issue makes no sense whatsoever. See also fast comments where all these issues are discussed in detail.

Best wishes

reader jbg said...

hi lubos,

yes, you are absolutely right with your remark. too much scientific knowledge has been (and still is!) sacrificed on the altar of religion...

however, i would like to comment from two sides.

the switch from fundamental physics to the study of (real) complex systems [1,2] constitutes in my opinion an important paradigm shift: from formal mathematical representations to computational simulations. i.e., the analytical vs. algorithmic description of reality [3].

within this context, the climate is obviously a full blown complex system, with many of the traits associated with such systems: adaptivity, self-organization, emergence,... or more formally: non-linear feedback/coupling, stochastic fluctuations, path-dependence, ...

So in essence, our knowledge of the climate, with all its dependencies, is pretty small. Although this conclusion should be equally applicable to climate septics and concerned people, the scientific community appears to be converging towards a consensus. indeed, even the economy is shifting [4], which indicates either the opening of new opportunities for revenues or a mitigation attempt regarding an impending threat.

in addition, the whole climate debate and concern is centered solely around the physics. however, no one knows how the system of all living organisms will react as a complex, adaptive, structure-forming process to the changes induced by human activity, whatever it may be.

secondly, considering the possible magnitude of damage for the future of life on earth, i'd rather err on the side of being too concerned and take responsibility for my and humanities actions than underestimating a cataclysm because, well, the causal connection is not proven, there is so much uncertainty, it's all just a conspiracy of eco-alarmists, it was warmer in the past, ...

in the end it doesn't really matter. the history of life witnessed many extinction events. perhaps conscious beings would never have evolved if this history were altered. and finally, all of life will end anyway with the sun entering its red giant phase (unless life colonizes other planets, where the ultimate fate of the universe will set an upper bound to its existence).

but for the immediate future, there is a big difference every individual can contribute to the collective behavior of humanity, increasing its collective intelligence form something resembling cancer (rapid uncontrolled growth; invasion and destruction of adjacent tissues, i.e., the ecosystems); colonization, ...) to something more symbiotic...

with best regards,


[1] complexity: introductory literature
[2] short summary of complex systems
[3] fundamental vs. complex
[4] e.g. the economist, very skeptical and supportive of b. lomborg up to then: the heat is on;
or swiss re: tackling climate change

reader Unknown said...
This comment has been removed by the author.

reader jbg said...

dear lubos

(sorry for having posted under the wrong alias noon_ch and then deleting...)

i really don't want to appear pedantic or ranting, and i'll shut up after this post, but i just would like to state some personal opinions which are drawn from experience and observation.

- in switzerland the tourism industry and some affected communities are concerned about melting alpine permafrost (which holds the loose rubble together that would otherwise cause debris avalanches hence threatening inhabited areas) and melting glaciers; theses developments have partly become acute in the last decade

-it is not about global warming per se, it's about the increase of local extremal climate events. take switzerland in the last year as an example (sources are various swiss media)
- In Switzerland many places experienced the warmest July in 2006 since the beginning of temperature measurements in 1864.
- September 2006 was the warmest September in the last 150 years for the whole of Switzerland.
- October 2006 was the second warmest October in the last 150 years for the whole of Switzerland.
- November 2006: it was the warmest autumn in Switzerland ever recorded.
- January 2007 was the warmest beginning of year since the start of measurements
- In the south of Switzerland, the temperatures reached up to 24 degrees Celsius on the 18th of January 2007 (beating the record of 13th of January 1920 with 17.3 degrees Celsius)!
- August 2006 was the coldest August in the last 26 years for the whole of Switzerland (mostly colder than january 07).
so we have nearly 6 months back to back with extreme values.

- the 10 warmest years since temperature measurements began 140 years ago were all after 1983

- it would appear naive to disregard the impact of anthropogenic greenhouse emissions (increase of approx. 16% in 50 years) on the climate system; especially if one considers the importance of path dependence (random fluctuations being enhanced) in the evolution of complex systems and the possibility of lock-in mechanisms reducing the possible future states of the system

- i do not have training in climate science, i.e., my personal opinions aren't very relevant; this is why it is so important to have scientific communities; not to say that consensus proves anything, but it would be a gross mistake and arrogant to ignore the people who have professional training in their field, the people who engineer and set up experiments, who interpret the data and the uncertainties, and then develop and empirically try and validate models

- the climate septics appear to be doing exactly the same things they are accusing the climate scientists of doing: the great global warming swindle (e.g., distorting the data, leaving one of the main scientist feeling "completely misrepresented", ...)

- i find it comforting that many young people take the threat of a changing climate seriously, as they are the ones who will have to deal with it

- finally, i find your take on the whole issue to be also somewhat "religious" and fanatic

i really don't expect you to find any of this relevant or true, but it felt good writing it:-)

all the best,


reader Goldsaver said...

So James, your argument is that the weather systems are so complex that we should not pay attention to empirical and geological data but instead look at computer models and accept the great "consensus".
And, since the possible consequences of the possible effects, possibly predicted by the computer modeling is so grave, we should ignore the actual physical world indicators (receding seas in the Maldives, thickening ice cap in the south pole)and accept the faith of Gaia (Algore is her prophet)

How about the known effects of government mandating the reduction of CO2 production in the US to half the output levels of 1990 (the newest "goal")How about rolling brown outs in the US (no nuclear power plants, so we must reduce power plant operations), etc, etc, etc.

reader Unknown said...
This comment has been removed by the author.

reader Alan said...

The best theories usually have a habit of being quite simple ideas. If you rely on fogging the issue by resorting to 'complexities' to deflect criticism then either your theory is flawed or just plain wrong or perhaps your perspective is wrong. If CO2 is the driver of global warming, it seems like a one-way ticket to disaster where beyond a certain point you can't prevent the rise in temperature continuing indefinitley because the earth can't handle it. What caused the much bigger rises in temperature in the past? To believe that is clearly a case of the tail wagging the dog. But then there are old fashioned scientits and there are new fangled environmentalists. However, it's just so much easier to accept the obvious. And if it turns out to be different for some other reason then, hey ... we can still be friends!

reader Unknown said...

This was an interesting read but I think you're getting muddled in the details to some extent and missing the big picture.
Whether it is CO2, CH4, or temperature leading the cyclical change, it still doesn't change the fact that the CO2 levels right now are way out of line with historical numbers. You reference when Al Gore went up on the lift to show where the CO2 levels are now. The drastic increase directly corresponds to the start of the Industrial Revolution. With CO2 levels currently at these high rates, it would follow, based on the historical data, that something will cause the temperature to stay in step with this rising level.

reader Luboš Motl said...

It's amazing, Mike, but you haven't understand anything about this issue at all, not even an infinitesimal piece.

CO2 might be at unusual levels in comparison with the last millions of years but the point is that CO2 is irrelevant. It is simply not true that temperature will adjust to CO2 to restore the r4relationship from the past.

The relationship is safely broken simply because in the past, CO2 was primarily absorbed or emitted by oceans depending on their temperature. Today, we create CO2 directly by our industrial activity and this creation has nothing whatsoever to do with the temperature.

reader Unknown said...

You say the CO2 has nothing to do with temperature and that temperature is dependent on some other unknown item. That being said, the amount of CO2 being generated at this time is in addition to normal, natural levels when you look at the data. Using your own thinking process, your argument for CO2 and temp being separate are as strong as mine saying that there may be some variable x that forces them both to move together.

The fact is, the temperature does cycle and is in a rising trend as everyone has known for the last few hundred years. As I said, everybody already knew that. You wil se a lot of debating going on saying that it's not CO2 and that it may be methane or something else that drives temperature changes. That's kind of besides the point. The fact is that no matter it is that causes the cycle, one thing is for certain, CO2 and temperature follow pretty closely in step for data going back about 650000 years as seen in the chart below. Now that CO2 is off the chart starting with the Industrial Revolution, the real question is what will happen to the temperature? This is where the big debate comes in but looking at the historical correlation, I would conclude that the temperature would try to stay in step with the CO2 levels. Your argument is it won't.

One other point that comes up is the lag. There is a 600-1000 year lag between CO2 and temp. The chart actually shows temperature rising before CO2 levels increase. This is why people say that CO2 levels are not a cause for alarm since the temp didn't go up first. That 800-year average lag is due in part to the time it takes the ocean to warm up. As it warms, it releases more and more CO2. The interesting part is that is what happened historically but not in the recent data as man started to multiply and burn things. There is no lag in the present data but a very close correlation. That is because the excess CO2 being put in is in addition to the normal levels that would be expected, i.e. we are piling more CO2 onto the plate that would not have been created naturally. This excess CO2 acts as an amplifier to the system and the temperature has been following this excess CO2 very closely. Again, if that is the case then the educated guess is that the temperature will soon follow.

If somebody comes back in 100 years and finds some flaw that the temp doesn't correspond then that would be great. Today there is a decision to make, take a conservative position of being prepared for the worst case temperature rise and combatting it by changing our habits OR do nothing and pray that you are right because if you find out you were wrong then it could be catastrophic as no plans were in place. It's a simple risk assessment, the consequences are catastrophic but the likelihood that it will occur is where the debate lies. I would rather be prepared than find out I was wrong later.

reader Anonymous said...

You know, the easiest way to solve this hole global warming debate is to go back and look at all the times in history that high levels of CO2 caused the oceans to boil off.........

(hint: it never happened...something about that whole "thermal equilibrium" thing; specific heat capacity; heat transfer coefficients...thermodynamics...hmmmm....donuts)

reader Unknown said...

This is a hopeless conversation as you guys already have your mind made up that your right based on partial observations. What's the point of discussing.

reader Anonymous said...

Actually, I do take this debate seriously; I just haven't seen adequate evidence to justify killing off most of the human race...which seems to be the only real viable solution according to our most extreme elements.

"Impoverish and eliminate" is not the rally cry I want to follow

reader Unknown said...

At least we can agree on that. There are extremes to both sides. To say that man, which multiplies like a bacteria, is not having an impact would be foolish, in my opinion. The ultimate answer to this whole thing is minimize the impact. By denying this, which may be correct, and digging your heels in, nothing will change and we will have a detrimental impact. Only through people with high visibility, such as Al Gore, can enough coverage be given so that people actually think about it and discuss it such as on this blog. To say for a fact that this is not true is one thing but to insist that our increased fossil fuel burning does not have a detrimental impact so we don't need to do anything to curb our impact is nothing short of foolish and arrogant.

reader Luboš Motl said...

Dear Mike,

I am not saying that CO2 and temp are independent. I am saying that during the most recent millions of years, to say the least, temperature was dictating the CO2, not the other way around. There is absolutely no doubt about this assertion and I won't accept any compromise about it.

Higher temperature means that oceans can absorb less gases which means that the rest is emitted to the atmosphere, regardless of the type of the gas.

This mechanism leads to a functional relationship between CO2 and temperature (and also methane and temperature, and others) that we observe in the past data.

It is trivial to show that this relationship no longer holds because there are also other mechanisms of generating CO2 that were not there during the ice ages but that do exist now - namely burning of fossil fuels etc. These new mechanisms imply that CO2 is much higher than it would be naturally but CO2 used to be a consequence, not a cause, so its changes do not affect the temperature in a significant way.

Imagine that someone has some ugly skin disease. Every day, it can be serious or less serious. Depending on his condition, people in the bus sit further from the ill man You can measure correlation between his illness and the average distance of the closest 5 people in the bus.

Now, the man doesn't like the people looking at him, so he also prints, in his factory, a poster saying that people should sit further from him. That's the role of industry.

People sit further from him, it's the first time he has a poster, but does it mean that his condition got more serious? According to you, it does. According to reality, it doesn't.

I am not saying that CO2 or methane is driving temperature changes. Quite on the contrary, I use the coherent motion of methane and CO2 to show that neither of them, and no combination of them, can be used to explain its (or their) correlation with the temperature because such an explanation wouldn't explain their (CO2 and CH4) correlation with each other.

If you can't understand these totally transparent facts and arguments, then you are mentally retarded and I just don't want you to spam my blog with your sick fantasies and confusion. Next time I will try to erase your idiotic "contributions". I know that my coexistence with pompous fools never leads to anything good and my policy about you is a protection of you, too.


reader Luboš Motl said...

Incidentally, the CO2-temperature relationship that used to hold during the ice ages and interglacials doesn't hold now and won't hold in the 21st century but it will approximately get restored in a few centuries. But what will happen is something else than you indicate.

There won't be any warming chasing the high concentration of CO2. Quite on the contrary. The "extra" CO2 from the atmosphere will be reabsorbed into the land, biosphere, and deep ocean. It simply takes a few centuries to remove the excess. The additional small warming caused by this excess CO2 will be undone, too.

So paleoclimate scientist in 500,000 years into the future will see that the well-known CO2-temperature correlation that they knew from ice ages continued even between the years 2000-4000 AD, with an extra peak of CO2 between 1800 and 2400 accompanied by a disproportionately insignificant increase of the temperature for a few centuries.

We can already observe that it's insignificant. The increase from 180 to 280 ppm during the ice ages was caused by warming by 8 Celsius degrees. But the increase from 280 ppm in 1800 to 380 ppm in 2000 is accompanied by warming by 0.7 deg C only, so it clearly violates the past relationship.

It can violate it because there is a new contribution to CO2 in the atmosphere that wasn't there - or wasn't significant - in the past, namely burning of fossil fuels. But there is no significant contribution to the temperature that could compete with the natural variations plus (or minus) 8 Celsius degrees during the ice age cycles. Even if we burn all of known fossil fuels, we can't cause 8 degrees warming, not even according to the shrillest activists.

The main point here is that CO2 is completely irrelevant and looking at CO2 as an oracle of our future fortunes or doom is a fashionable mental disease whose invalidity is trivial to see.


reader Luboš Motl said...

I am serious. I will be erasing your idiotic comments because it is guaranteed that their value is negative.

In your last one, you jumped to personal attacks and comments about George W Bush. What does he have to do with this topic? Yes, even though he is a kind of coward, I think he is a greater man than most of his critics, but what the hell does it imply for the temperature?

Stupidity like yours must be fought against and it must be done very systematically. It was neglected in the climate science and stupid arguments by stupid people were incresingly tolerated - and eventually we got to the present moment when climate science is more or less controlled by complete imbeciles.

I always appreciate that the number of idiots - and especially the number of nicknames they can invent - is far greater than what can be dealt with peacefully and I will simply not allow imbeciles to overrun my blog.

You can't understand that "A causes B" is something different than "B causes A"? OK, you must be eliminated.

reader Unknown said...

That is a much better explanation than before with no derogatory comments. I take back what I said now.

reader Unknown said...

I have a question, in case of this lag, wasn't it 800-1000 years? I would like to see how todays rising CO2 correlates with the period 800-1000 years ago. If I'm not wrong, the medival warming occurred about 1000 years ago so a part of the increasing CO2 levels now can be an aftermath of that period.

Best regards

reader Unknown said...

We have stated that CO2 lags temperature and as the temperature increases CO2 levels rise. The question is what causes the temperature to rise and fall? Is it sunspots, cosmic dust or possibly just a normal cycle of the oceans releasing and absorbing CO2? (probably not since those levels lag the temp) If something else is causing the temperature to rise and therefore raise CO2 levels which may in turn help to increase the temperature more, then something is causing the temperature to fall again even though we have high level of CO2 and CH4.

So what is it? Maybe by having extraordinarily high levels of CO2 we will cause the earth to be a bit warmer than it is supposed to be for a while, but think of the alternative. Based on the standard cycles going back 400,000 years we are at a peak in temperature. If the temperature were to plummet to those minimum levels life here would probably be a lot worse than adding a degree or two to our "max" temperatures.

The real issue here is change. People don't like to see things different then when they were a kid. If there was snow in Colorado when they were growing up then there should still be snow now. Of course some of the change may be a bit more severe like having beach front property at Lake Okeechobee Florida.

reader Luboš Motl said...

Dear Paul, thanks. The true driver should have been discussed here, too.

The normal theory - accepted by scientists across the ideological divides - are the Milankovitch cycles, i.e. the periodic oscillations in subtle parameters of the Earth's orbit such as the eccentricity and the angle between the rotation axis and the plane of orbit.

There exist alternative theories where the underlying reason is a new kind of "acoustic" wave inside the Sun.

Well, it could be something else, too. But it can't be "just" chaos because the Fourier transformation seems to be focused on pretty well-defined frequencies.

All the best

reader Unknown said...

The a-ha to me was the realization that whatever the IR absorption of CO2 is, it is limited. CO2 may have a strong carbonyl absorption but it is also a very narrow band. This means that overall it is a weak greenhouse gas, and its ability to absorb more IR by adding more CO2 is minimal because within the absorption band the available IR is already absorbed. Now I'd be very interested to know whether or not there is any published maths to back this up based upon the abosrption potential and concentration of CO2 in the atmosphere. Anybody know?

reader jjgdo said...

Dear Group,
I am a physician and I get little time to explore for info. This Blog is a rare treat for me.

I have a liebral friend who tells me many things that I find hard to confirm. The lag of Co2 I learned about watching that climate movie the great Global Warming Swindle. This finding is soo significant, yet the world seems to not notice this. Then my friend tells me that the ice core data shows the oposite claiming that temperature lags CO2. I have not been able to find any good reference to verify his claim, but plenty to back up the data as presented here. I am very sick of people who make false claimes and I have to say that I believe the same people lack rational skill. I agree with the moderator that when you realize that someone will not deal rationally, it is time to treat them as an enemy. Our very lives depend on rational thought, and the people who work against it are now very numerous and powerful. I am not sure that our sivilization will survive them at this point.


reader Bloefeld said...

I cannot link to the article regarding the positive correlation between carbon dioxide and global temperature. I have been looking for such a link for a long time.

The time lag for me is the killer to the causal link between climate change and carbon dioxide.

Your comment with regard to the temperature change since the start of the industrial revolution is one I had failed to see. Obviously it is the only one that has any sort of basis to the claim of the effect of human influenced change in temperature.

However of course this must be tempered with the difference in human population between then and now.

Finally I think the most offensive thing about the various solutions is that they all cloak the reality that population growth is a big part of the equation and that the solution is truthfully repulsive.

Having said that Al Gore's former boss, claimed that he didn't know there was a genocide happening in Rwanda or he would have done something about it. How on earth would the President of the United States not know about it when I knew about it from reading the Economist magazine.

I find it little comfort that the Al Gore's of the world put a higher value on their own lives than they do to say mine or others who live in countries that are "over populated" as if their murder by starvation because he is worked up about some incredibly unproved theory is more important than first finding out the truth about the theory and then deciding if bringing us all down to a level of poverty equal to that in the third world is really the answer.



reader Unknown said...

Guys, I think your science is flawed, primarily in the assumption that there is a simple one-way causal relationship between temperature and CO2 (of the form x => y) and if temperature rise comes first then temperature is x and CO2 is y, world without end amen.

The crux of the argument is whether the climate system behaves this simply, or whether it has properties which are more similar to those of an organism or complex machine (likely), in which case the cybernetic principles of positive and negative feedback loops are more relevant.

In a positive feedback loop, phenomenon a causes more of phenomenon b, and b in turn facilitates more of a, which causes more of b, and so on, so you get what a friend of mine once delightfully termed a "vicious snowball".

In a negative feedback loop, phenomenon a causes more of phenomenon b but b tends to inhibit a so the process is self-limiting. An example of this from mammalian physiology is the hypothalamic-pituitary-adrenal circuit which controls the stress response. Something startles you, adrenalin gets released into your system and you get wired for action, but this hormone release also triggers the release of adrenocorticoids which bring you back down. In case of chronic stress the system can't dispose of all the adrenalin, the excess steroids affect your immune system, and you become ill.

Another example is a steam engine with a governor.

The important point is that the causal relationship operates in both directions - the old chicken and egg - and it makes more sense to represent temperature and CO2 emissions as points on a circle.

In the case of climate (I'm not a climatologist but this is how I understand it), a temperature rise caused by solar activity may well have been the start of a cycle which releases CO2 and other greenhouse gases. Under normal circumstances these would indeed be reabsorbed by the oceans, constituting a negative, and hence self-limiting, feedback loop. (the greenhouse effect from low concentrations of CO2 would not produce enough of a rise in temperature to affect the oceans' ability to absorb most of the CO2, and further rises in temperature would thus be prevented).

But with the addition of high concentrations of man-made greenhouse gases, the systems in the loop come under pressure because the additional greenhouse gases raise temperature further - so temperature rise causes CO2 which causes more temperature rise which causes more CO2 etc. (I think this provides an adequate explanation for the correlation with methane.)

In other words, the reabsorption system (the negative feedback loop), will work up to a point (a so-called tipping point), but at some level of emissions it will become unable to cope with the increased stress on the system because the upward pressure on temperature caused by the greenhouse effect becomes too great, and the negative feedback loop changes to a positive feedback loop, at which point we move into runaway climate change.

Currently, climate scientists treat the world's climate as a complex system, which means that modelling it according to systems principles makes sense. It's not as easy to do precise science like this, but that doesn't make them unscientific. Speaking as someone with 2 degrees in Mathematics who has gotten interested in the life sciences late in life, I would make this remark: if you don't think that extraordinarily complex and difficult-to-model systems can emerge from a few basic chemical elements and processes, have a look at a Mandelbrot set! ;)

As for the relatively low rise in temperature accompanying the steep climb in CO2 concentrations, you've made much of the 800-year lag between temperature rise and rise in CO2 concentrations. I would think it's quite likely that the lag between increased CO2 and increased temperature is also long when the causal relationship is operating in the opposite direction. To me this says that an extremely conservative and worst case approach is a sensible one, because a tipping point crossed now may result in severe warming decades or even centuries into the future; but once the tipping point is past, the process is irreversible because the loop becomes self-perpetuating, and it's on a scale which humans can have very little impact on.

If that makes me a left-wing imbecile, I shall wear the label with pride!! ;)


reader Luboš Motl said...

Dear caroline,

saying that the Earth is like a living "complex" kitty is surely cute ;-) but it is a religion, not science, so let me leave this issue to religious blogs. I don't know what to say about this poetry. The Earth has surely some extremely vague qualitative similarities to animals or computers or anything else you can think of, but it also has important differences. ;-)

Saying that the Earth is just like a kitty doesn't solve anything because for any detailed question, the analogy can either be correct or wrong and the answer is not a priori known.

Another issue. The hypothesis that the CO2-temperature system is an unstable positive feedback system can be easily falsified - and it's been ruled out on this page - by several independent arguments.

If the climate were an unstable positive feedback system in your sense, it would have already run out of control - exponentially - sometimes during the 5-billion-year history of the Earth. Because that hasn't happened, the climate can't have this instability you mention. It is a stable system dominated by negative feedbacks, much like most "long-lived" systems we observe in Nature.

The lag - and the other, theoretical arguments - shows that even if the relationship were going in both ways, and it surely does when we look very accurately and when we include "academic" effects, the impact of temperature on CO2 is much stronger than the influence of CO2 on temperature (i.e. than the greenhouse effect).

The ratio of these two influences over the historical epochs is exactly what the lag measures. If the greenhouse effect were an important effect - or even one of the leading effects in the climatic history of the Earth - the lag would have to go in the opposite direction.

So I am not saying, and I was never saying, that the greenhouse effect is zero. I am saying that it is smaller than all the other effects that are behind the graphs and correlations (namely outgassing), it can be neglected, and there is no statistically significant paleoclimatic evidence that the CO2 greenhouse effect has ever played a detectable role for the climate.

The greenhouse effect has been by 1 order of magnitude less important than outgassing (the opposite influence) simply because the 100 ppm variations of CO2 were *caused* by changes of temperature by 8 degrees Celsius or so (ice ages vs interglacials) while the man-made added 100 ppm has led at most to 0.8 °C of warming (and probably significantly less, because the Sun and PDO etc. have played important roles, too).

This pretty much means that with the available accuracy in paleoclimatology, the CO2 effects on temperature couldn't have been observed. CO2 will only become progressively detectable if its concentration really exceeds the historical variations significantly. We're not there yet and the CO2 effect can't be separated from the other drivers such as PDO, ENSO, solar activity, albedo changes, aerosols, and others.

Best wishes

reader Unknown said...

Lubos, thank you for an intelligent reply.

I don't recall saying that the earth was like a cute kitty, which seem to be a bit of an ad feminam argument ;), but never mind. If the earth demonstrates properties which are similar to those of a living system, and if theories of complexity do a better job of describing and predicting climate processes than simple mechanistic models do, then it's good science to use the most accurate model. If the simpler model doesn't describe the phenomena as accurately, then Occam's Razor (parsimony) doesn't apply.

I agree - it looks as though the effect of greenhouse gases on temperature is less than the effect of temperature on production of greenhouse gases. But is the increased production of greenhouse gas, plus albedo due to shrinking icecaps & loss of cloud cover over rainforests, permafrost melting, etc, taken together, enough to push a previously stable system governed by negative feedback loops into a new state in which a positive feedback loop emerges?

You seem to be saying it's not whereas most climate scientists are saying it is, and the only way to argue that is by getting into the guts of their models. However, I think it is valid to say that the climate system cannot be regarded as closed, and that emissions produced by humans represent a factor never seen in paleoclimatology. To reach a point of dynamic disequilibrium, it's not necessary for emissions levels to cause temperature rises similar to those caused by solar cycles. They just need to cause enough to destabilise the system, because their effect is not "instead of" but "as well as".

So if we are in a natural warming cycle anyway, they could tip the balance. And the whole point about a tipping point (if you'll pardon the pun) is that the future behaviour of the system can no longer be predicted from the past behaviour of the system.

Emissions also don't need to destabilise the system totally (I don't think carbon emissions are going to cause the earth to erupt into a ball of flame ;)), just enough to trigger or speed up a process of making it uninhabitable for more advanced life forms, something that has happened before in geological time.

And again, to determine the probability of this happening, one has to dig into the guts of the mathematical models, and I don't think a simple causation argument like yours is capable of answering this question, which is probabilistic.

At this juncture, the fairly scientifically literate but casual reader (like me) steps back and says: "what does the meta-analysis say?" There will always be results which run counter to the main body of research, but if the bulk of peer-reviewed research suggests a high probability of human activity having a deleterious impact on climate, then it's only common sense to take action. There's a lot wrong with science as practised today, but there's a lot right too - it's not an opinion poll.

(A good analogy is the link between smoking and lung cancer. You will find individual studies which show clearly that there is no link - and diehards who swear that there isn't one based on such-and-such a study - but if you look at the body of research, the vast majority of studies show that there is indeed a link. Certainly the discovery that oat cell carcinoma results from mutated macrophages is good enough for me. Science is not about certainty but about incrementally increasing the probability that one's deductions are correct.)

So the short conclusion is: although you've clearly given it a lot of thought, I'm not buying your argument.

Anyway, as a left-wing, feminist imbecile, I rather like the idea of a clean, green, ecologically sustainable planet with lots of cute kitties running around! ;)

Best of luck with your blog,


reader Luboš Motl said...

Dear Caroline,

if I had used a male dog instead, I would have been also criticized: for using male chauvinist ideas. So I had no choice. ;-)

In some sense, it's surprising that you as an alarmist argue with "complex systems". The point of most alarmist modelers is, on the contrary, that the climate is very predictable and essentially "linear" and all chaotic features can be neglected.

I agree that science is about incremental additions to our knowledge. The only additional subtlety is that as we're adding more, we're learning that the truth is increasingly far from the environmentalists' opinions.

If you presented other arguments against mine, then sorry, they remained hidden in your writing. ;-)

Finally, if you like kitten, you should support intense efforts to warm the planet, or at least not to cool it. "Most cats seem to prefer warmer temperatures than what we might like." Click the previous sentence to see it at its source.

Best wishes

reader Alex D.G. said...

Hi Lubo.

I'm sorry, my english might be bad, I'm a french canadian.

I have to say that I am glad to finally read something that explains so well the climate change even if your opinion doesn't "fit" the global opinion according to the IPCC.

I frankly don't know yet on which "side" I'm standing, I'm still trying to forge my opinion.

So here's my question: How the whole IPCC team could be so wrong?
What would be their motive to spread an idea so false?

On the otherside, I can understand why Al Gore was so motivated to recycle his political career to an "environmental prophet spreading awareness" ;P :

The Money and Connections Behind Al Gore’s Carbon Crusade


reader co2isnotevil said...

There are a few other things to consider. First, the models tend to violate Conservation of Energy by double counting energy, They universally count energy re-emitted as the result of greenhouse gas capture as new energy entering the system while it is really just a delayed form of incident solar energy. Second, the evolution of an ecosystem adapting to temperature change explains most of the CO2/CH4/temp record and is the only factor, other than the ebb and flow of ice, that has time constants on the order of centuries. See this for a complete analysis of the data:

reader Luboš Motl said...

Dear CO2 is not evil,

concerning your second point, the correlation is completely dominated by outgassing, the temperature-dependent ability of oceans to store gases.

Concerning your first point, you are completely right in what you write explicitly - the reemitted energy is just "delayed" solar energy.

But you're wrong about one assumption that you don't articulate explicitly - namely the assumption that the lag doesn't matter. It does matter. Thw lag is the whole reason why the equilibrium temperature is higher in the presence of the greenhouse effect. The lag means that the ability of the system to cool down is reduced - much like a covered pot where you cook soup.

Best wishes

reader co2isnotevil said...

The outgassing operates over very short time scales. Try an experiment to see how long it takes carbonated water to go completely flat. The lag from temperature changes to CO2 changes seen in the ice cores is on the order of a century or more. The temporal resolution in the ice core samples is too coarse to see the effects of outgassing. It's also too coarse to see the direct effects incremental CO2 has on energy absorption.

Regarding the lag of releasing surface energy, this does have a surface temperature effect, by virtue of the pool of energy being stored in the atmosphere, but increasing the CO2 concentration does little to change the amount of energy stored in this pool. CO2 is such a good greenhouse agent, that most of the effect is can have kicks in at very low concentrations.

The problem with many models is that they consider energy re-radiated via greenhouse absorption as input energy that effects the energy balance. If you consider the entire Earth, as seen from space, the energy leaving the planet is the same as the energy coming in, independent of greenhouse concentrations.

The analogy about the pot is missing one piece, which is that the effect of CO2 is like covering the pot with a screen, where as the effect of clouds is like a solid cover.

reader Luboš Motl said...

Dear CO2 is not evil,

you completely misunderstand outgassing and because I am kind of certain that every intelligent reader must have gotten it, even by reading this very point, I hesitate whether it makes sense to say something more.

At any rate, in outgassing, one doesn't talk about the effects of CO2, but on the contrary, about the effect on CO2 and other gases. And the lag is huge, experimentally measured to be those 800 years, and it is so long simply because the relevant absorbing layers of the oceans take many centuries to cool down or heat up.

You are also wrong that changing CO2 concentration in the air has no impact on concentration in the water. Under fixed (other) conditions,
these two things are actually proportional to one another, according to Henry's law. What temperature changes is the ratio of the gas in the water and in the atmosphere, i.e. the distribution.
Best wishes

reader co2isnotevil said...

The time constant for the oceans release of stored energy is not centuries. If you add up all the energy it took to raise the temperature of the ocean from the freezing point, it's only about 17 days of incident solar energy (after accounting for the albedo). Another thought experiment is to consider how long it would take the Earth to become a frozen wasteland if the Sun were to stop shining.

Regarding the time lag, the 800 years was derived from Vostok data, but the uncertainty is relatively high. The Dome C data shows about a 200 year lag from temp change to CO2 change and about a 600 year delay from temperature changes to methane changes. This is more certain owing to more samples and shorter sample intervals. It is also more consistent with the signature of an ecosystem adapting to temperature change.

reader Luboš Motl said...

Hi, the calculation based on the amount of heat from a Sun that is turned off/on has nothing to do with the actual time scales that matter.

The Sun is never turned off - at least not for additional billions of years - and globally, the amount of heat we receive from the Sun per year is constants with accuracy that deviates by much less than 1%.

So the global ocean temperatures never fluctuate by 15 deg C in 17 days. In fact, they only change by fractions of degrees in many decades. When the actual realistic stability of the energy budgets is taken into account, the changes that you attribute to 17 days occur in 5 years, the time constant for the upper ocean.

For deeper ocean, the heat conductivity is actually so small that even this counting fails and one has to rely on physical circulation of the water. It takes about 2,000 years for the deep ocean cycles to circulate, and that's the time scale at which we exchange heat with the deep ocean.

Your indication that the 800-year lag is zero and it is all illusion is just preposterous. It's measured in dozens of independent places and proper models explain why it takes so much time, too. Unlike your guesses, they use realistic models for the nearly balanced energy budgets and realistic numbers for the heat conductivity which is surely not infinite.

Your writing is the kind of writing that justifies some alarmists' hints that climate skeptics are crackpots - it's just that the generalization to all skeptics is wrong.

reader barry said...

Having read 50 papers n this topic and scanned 50 more, I think I understand the theory.

There is no doubt whatsoever that orbital varations (the trigger for quaternary ice-ages and deglaciations cause nslation changes that are to weak to account for the amplitude of warming/cooling. The very highest value given to the contribution to warming amplitude in deglaciation is 20% - in a single paper. The mean contribution amongst the studies I checked is much lower.

The two main amplifiers of the initial trigger from orbital changes are ice sheet and GHG changes. The mean contribution of all GHGs from the studies I read is about 50%. CO2 by itself is 30%.

Lubos, you referenced Caillon 2003. That paper also assigns a significant amplifying effect from CO2 during deglaciation (Termination III). I know of no post-80s peer-reviewed study that contradicts this thesis.

CO2 lags by approx 800 years (that is an estimate, not a final number and vulnerable to further revision in the future), but warming continues for another 4200 years on average for the various terminations. It is held that GHG increase accounts for a major portion of the warming once CO2 starts rising.

There is no question that increased GHGs in a volume of earth atmosphere atmosphere cause warming - this has been verfied in lab tests myriad times and is now an empirical fact, and verified by spectral analysis of the atmosphere over time from lidar readings on satellites. The question is; how much?

Much of the misunderstanding on this topic can be traced to a prediliction for a binary cause and effect situation, where one thing cases and another and that's that. Caroline described it well upthread. To whit, a causes b, which causes more a, which causes more b etc. In the case of Milankovitch cycles, orbital variations bring more insolation to high latitudes, melting ice sheets and warming the oceans, causing outgassing of CO2. Temp does lead CO2. As orbital variations bring the insolation to lower latitudes, the pole cools, ice sheets reform, oceans cool, and the CO2 starts dropping. There is also an in-built limiter in the logarithmic effect of CO2 on warming.

The saw-tooth shape of the ice age time series fits our knowledge of the carbon cycle. As ice sheets melt they uncover buried CO2 (dead plants, raleased from ice and oceans via evaporation) and the oceans warm, which makes them less soluble to CO2. As ice sheets grow and vegetation gets sparser and strata are covered by ice, the CO2 sinks decrease and CO2 decreases happens more slowly, as it takes longer for CO2 to be absorbed by geological sinks. There are other processes at work, of course, but these are the main cycles to our best understanding. The largest signals are ice sheet change and GHG change.

As far as I've read, which apears to be more than most who comment on this issue, the lag of CO2 doesn't undermine AGW theory. It's worth noting that the earliest mention of a possibe lag is in a 1976 paper on ice ages. there is another mention of the possibility of a GHG lag in a 1990 paper (co-authored by Hansen - the Lorius study). While the phase lag impacts quantifcation of the greenhouse effect during glacial canges, it doesn't reduce its significance in the process.

I am not pushing AGW here. I'm neutral on it. Just sharing my understanding of the many papers I've read on the subject. My take is that the CO2/lag argument s not a strong case against AGW theory.

(If you wish, I can cite numerous papers to corroborate)


reader barry said...

Having read 50 papers n this topic and scanned 50 more, I think I understand the theory.

There is no doubt whatsoever that orbital varations (the trigger for quaternary ice-ages and deglaciations cause nslation changes that are to weak to account for the amplitude of warming/cooling. The very highest value given to the contribution to warming amplitude in deglaciation is 20% - in a single paper. The mean contribution amongst the studies I checked is much lower.

The two main amplifiers of the initial trigger from orbital changes are ice sheet and GHG changes. The mean contribution of all GHGs from the studies I read is about 50%. CO2 by itself is 30%.

Lubos, you referenced Caillon 2003. That paper also assigns a significant amplifying effect from CO2 during deglaciation (Termination III). I know of no post-80s peer-reviewed study that contradicts this thesis.

CO2 lags by approx 800 years (that is an estimate, not a final number and vulnerable to further revision in the future), but warming continues for another 4200 years on average for the various terminations. It is held that GHG increase accounts for a major portion of the warming once CO2 starts rising.

There is no question that increased GHGs in a volume of earth atmosphere atmosphere cause warming - this has been verfied in lab tests myriad times and is now an empirical fact, and verified by spectral analysis of the atmosphere over time from lidar readings on satellites. The question is; how much?

Much of the misunderstanding on this topic can be traced to a prediliction for a binary cause and effect situation, where one thing cases and another and that's that. Caroline described it well upthread. To whit, a causes b, which causes more a, which causes more b etc. In the case of Milankovitch cycles, orbital variations bring more insolation to high latitudes, melting ice sheets and warming the oceans, causing outgassing of CO2. Temp does lead CO2. As orbital variations bring the insolation to lower latitudes, the pole cools, ice sheets reform, oceans cool, and the CO2 starts dropping. There is also an in-built limiter in the logarithmic effect of CO2 on warming.

The saw-tooth shape of the ice age time series fits our knowledge of the carbon cycle. As ice sheets melt they uncover buried CO2 (dead plants, raleased from ice and oceans via evaporation) and the oceans warm, which makes them less soluble to CO2. As ice sheets grow and vegetation gets sparser and strata are covered by ice, the CO2 sinks decrease and CO2 decreases happens more slowly, as it takes longer for CO2 to be absorbed by geological sinks. There are other processes at work, of course, but these are the main cycles to our best understanding. The largest signals are ice sheet change and GHG change.

As far as I've read, which apears to be more than most who comment on this issue, the lag of CO2 doesn't undermine AGW theory. It's worth noting that the earliest mention of a possibe lag is in a 1976 paper on ice ages. there is another mention of the possibility of a GHG lag in a 1990 paper (co-authored by Hansen - the Lorius study). While the phase lag impacts quantifcation of the greenhouse effect during glacial canges, it doesn't reduce its significance in the process.

I am not pushing AGW here. I'm neutral on it. Just sharing my understanding of the many papers I've read on the subject. My take is that the CO2/lag argument s not a strong case against AGW theory.

(If you wish, I can cite numerous papers to corroborate)


reader Unknown said...


No serious skeptic denies that changing greenhouse gases have some effect. The point is that this effect is far smaller than the effect from the ebb and flow of ice. This effect is quantifiable with contemporary satellite weather data and is all that is needed to explain the 'amplification'. There is no need to *ASSUME* that GHG is a significant component.

Perihelion occurs in Jan, where about 80 W/m^2 more incident energy arrives from the Sun, which translates into about a 3.5 increase in surface temperature (AGW sensitivity of 0.8 predicts a 16 C increase, which is clearly not evident).

The satellite data shows a 4C decrease instead. The net 7.5 degree decrease is due to the seasonal reflectivity of northern hemisphere snow which just happens to align with perihelion.

If the surface was covered in ice, then this 7.5C would be a static offset and not just a seasonal aberation. The changing earth's tilt makes this difference even larger, which is all it really takes to explain the 12C difference between ice ages and interglacials.


reader Bloefeld said...

Hi Barry,

Very interesting comment and clearly well researched.

How much leverage with regard to increase in temperature and increase of CO2 exists. The relationship does not seem to be as linear as some suggest.

The data appears to me to suggest that the first hundred or so PPM increase has much more effect than the subsequent 700 or 800 PPM seems to have.

Everyone on this forum has toe-nail clippings that know more about this than I do, so I am curious to hear others thoughts on this relationship.

In your comment you mention that CO2 seems to be the biggest component to increase in temperature. That is something that I believe is still out to question.

My belief (opinion) is that we are concentrating on the changes in CO2 less because they have the most leverage on temperature, but more on the ease we have in dating this data with ice-core analysis.

So, if I am correct; it seems to follow that nearly every solution to meet energy needs creates more gases like water vapor and oxides of nitrogen than they reduce lower leverage gases like CO2.



reader Unknown said...


We are concentrating on CO2 because of a presumption that CO2 has the most effect. This concern became amplified when Hansen hooked up with Gore and the IPCC transforming his pet theory of AGW into a political issue. This allowed a consensus to arise without the requirement for scientific rigor, which he could not provide, but thought would surely come eventually. You know, the old 'ends justifies the means' argument.

To his credit, Hansen did all the right things by collecting the data he thought he needed to prove his case, however; at every turn, the data shows exactly the opposite of what he expected. His data is a rich source of contradictions to the AGW hypothesis, but this is not made widely known.

The real science will win in the end and AGW is not real science. Solar variability, orbital variability, the ebb and flow of ice, water vapor and weather are just some of the more important factors. The relative effect of incremental CO2 is small enough that it's nothing to worry about and certainly not enough to justify a multi trillion dollar experiment in climate control just to find out.

CO2 is a popular scapegoat because it offers a false sense of salvation, whose implementation just happens to align with a variety of radical agendas. It bashes oil companies, capitalism, success and it was a good Bush bashing tool for Gore.


reader barry said...

Hi Bloefeld,

How much leverage with regard to increase in temperature and increase of CO2 exists. The relationship does not seem to be as linear as some suggest.

The relationship is logarithmic. When feedbacks are factored in (water vapour, ice sheet eyc), the inclination of the temp profile increases. So says the mainstream. For CO2, each doubling of concentration in the atmos produces roughly the same amount of warming.

In your comment you mention that CO2 seems to be the biggest component to increase in temperature. That is something that I believe is still out to question.

CO2 is not the only thing affecting temps, of course. My comment was related strictly to the understanding of glacial terminations. Ice sheets is another significant forcing. I meant to be careful to distinguish between CO2 and all GHGs. Generally, the studies that I've read give prominience to all GHGs at terminations (NO2, CO2, CH4). I'm not sure if water vapour is factored in to that result, but it s certainly consideredto be part of the warming. Isolating CO2, ice sheet forcing may have an equal or even greater forcing value. The relative contribution between the two has error bounds that overlap.

My belief (opinion) is that we are concentrating on the changes in CO2 less because they have the most leverage on temperature, but more on the ease we have in dating this data with ice-core analysis.

Yes, it is easier to extract the GHG (not just CO2) signal from the ice core and other proxy data, as it is to winnow the temperature change. More difficult to quantify are ocean circulation, cloud changes, vegetation change etc. Of the forcings fairly well understood, about 90% of the temp amplitude is believed to be accounted.

As I understand it, the reason CO2 gets a lot of focus today is because it is the fastest changing component in the atmosphere. During deglaciation, CO2 concentrations increased by roughly 90ppm over 5000 years. More recently, CO2 concentrations in the atmosphere have increased by about 110ppm over 150 years.

We're in danger of going off-topic and into areas I've not researched as much. :-) But I will look for any reply you may post and do my best.


reader Bloefeld said...

George and Barry,

Thank you for your insights. I have a better understanding of the issue now.

George, you and I clearly agree on the real issue. I believe this topic is now so much ruled by consensus that actual scientific query is next to impossible to prove or disprove anything related to it.

I point to President Obama's chief science guy John Holdren, who during the election stated in an interview in London that: The debate is over, and the only people who disagree are morons or Republican's.

It seems that many would take his statement to task, expecially those who are true skeptics and are merely trying to find the truth of the matter.

This board is a perfect example, I doubt if everyone meets Dr. Holdren's necessary and sufficient conditions to hold a contrary position to his.

He is an interesting guy; he was part of the group at Berkley who created their own department of the environment and then conferred PhD.s on themselves to give their view credibility.

They are all in some way connected to Dr. Paul Erhlich who made the famous prediction that as a result of over-population the population of the US in 2000 would be 20,500,000 people living like wolves. He based his prediction on a set of statistics designed to predict the stock market and its cycles.

Now however he and his pals are not just harmlessly bad statisticians. They hold power and are dismantling the concept of academic freedom throughout America.

Getting funding to study global warming if you are not already a 'true believer' is said to be difficult or impossible. This will lead to bad outcomes in the end, because the solutions proffered could well be either destructive to the lives of individual humans on a massive scale, and detrimental to the ability of third-world nations to develop economically.



reader barry said...

I point to President Obama's chief science guy John Holdren, who during the election stated in an interview in London that: The debate is over, and the only people who disagree are morons or Republican's.

It seems that many would take his statement to task, expecially those who are true skeptics and are merely trying to find the truth of the matter.

If I may attempt to put that in context...

There are, of course, many uncertainties in climate science. Clouds and aerosol forcing are just a couple. In terms of projections, no one can tell how much CO2 will be pumped into the atmos in the future. Even within the various scenarios (parameters include more than CO2 rise) there are differences in model outputs.

I believe that 'the debate is over' refers to the general contention of AGW, not the factors that are clearly still under discssion. That is (quoting George) "No serious skeptic denies that changing greenhouse gases have some effect." Simply put, we expect that adding more greenhouse gases to the atmosphere will impede the outflux of longwave radiation, thereby retaining more heat n te atmosphere. While certain feedbacks are not well-known, it is assessed that the unknowns will nt change the general concept. What is in question is the degree to which the globe will warm. Also uncertain (but not completely in the dark) is regional effects.

I presume that when people say "the debate is over", or "the science is settled", they are speaking to the general theory - industrial emissions are and will continue to warm the planet. No complex system like the climate system will likely ever be understood and predictable to the enth degree. There's still debate over fine points - at the very least.

I don't often like to comment on the political/social side of the argument, but it occurs to me that if scientists really want to get more funding (an oft mentioned rationale for illegitimate science), then they would be better off saying that the possibility of global warming is there, with its attendant ill consequences, but that much more money is needed it find out whether it in fact is going to happen. IOW, if the egg-heads want more fnding, they're sending out the wrong message.

reader barry said...

G (I named you George in the previous post - apologies),

I believe you're confusing weather with climate: seasonal changes with centennial: regional with global: perihelion and aperihelion with precession, eccentricity and oblquity (three orbital parameters associated with glacial changes).

IOW, annual seasonal variability is not equivalent to long-term climate change (I hope I haven't misunderstood your point/s).

There is no need to *ASSUME* that GHG is a significant component.

The significance of GHG forcing emerges from the studies. It isn't assumed. One thing that is common across all studies is that total insolation changes over the long-term (millenial) are too small to account for the amplitude of temperature change. In-system climate dynamics must therefore be responsible for most of the change, and of the 100 or so studies I've read, by far the majority either give prominence to GHG forcing, or posit aproximate equivalence to ice sheet forcing. There is more disagreement as to the phasing. A small number of papers (especially pre-1990s) give prominence to ice-sheet forcing, but this theory has fallen by the wayside as better resolution on ice cores has come about.

Obviously it would be impractical to link every study I've looked at (and I only saved a couple dozen to my hard drive), but I will cite a good number on request.

Nice to have a discussion without all the rhetoric and invective. Cheers.

reader Bloefeld said...

Hi Barry,

Unfortunately when something strays from science and becomes politically charged, motivations change.

Obviously there is no debate that the climate is changing; it is always changing.

That CO2 is a part of that change is also clear.

However, when wild-eyed predictions result, the public becomes fearful. This is a sign for politicians to hunt for the power that comes from 'saving' the public.

This is why I persist in trying to find some relatioinship between the amount of increase in GHG and the amount of climate change.

This is why I persist in asking my ignorant questions regarding the amount of leverage CO2 has on the system.

Statements made concerning the future should not look at simply CO2 as the only legitimate culprit for the fear that is being induced by the 'true' believers, but rather should also include the whole of the gambit of GHG's and other climate changing items.

So when Holdren stated that the debate was over, he was not discussing merely climate change, but rather gave the implication that CO2 was the main issue, and that not believing it, made one either a moron or a Republican. The inference being that it was impossible to be both intellectually capable and hold an alternative political viewpoint to that which he holds.
I think that there is little debate in the U.S. world of academia that certain topics are out of bounds for funding. These include climate change and as an example discussion about 'intelligent design.'

One should not have to agree with anything to do research on something. Academic institutions should be prepared to simply eliminate politics from decision making regarding funding.

I, like most people, are concerned about about mankind's role in changing the climate. However, I do not believe that simply eliminating sources of CO2 emissions will result in the necessary and sufficient conditions to reverse the change.

Rather I think that one should be careful about what is done. The solution should not do more harm than the problem.

So, when I see an ad for a Honda whose only emissions are water-vapor, I cringe because water is not just a harmless emission.

I cringe at the idea of hydrogen power; mainly because it creates so much free CO2 to generate hydrogen by the only economic means that exists, taking it out of natural gas.

The same holds true for battery powered cars; its as if the only issue is what issues out of the tailpipe of the car. Take into account the mining and refining of lithium, the very much limited amount of lithium in the earth's crust. Then add to that the treatments to materials to manufacture the barrier films needed to make the systems work, and all of the other sources of CO2 that are created (including generating the power to plug into) before declaring them to be a panacea.

What is being lost at the hands of those who forestall debate, like Dr. Holdren, is freedom.

Letting go of a freedom of any sort, is something that is to be done only after careful examination.

Setting up conditions where academic freedom is subject to any sort of a priori examination of beliefs, will result in the loss of science.

The Dr. Holdren's of the world, are much worse than any oppression on science ever put upon individuals by the Catholic Church. Regardless of your position on the niceties of what is happening to our climate, the loss of science at the hands of 'belief' is more dangerous by far.



I promise to leave this topic at this point. This forum need not be sullied by being dragged into too much discussion of this nature.

reader Unknown said...


Yes, orbital effects are related to ice ages. One of the more important ones is the precession of perihelion. Currently, perihelion is in early January when 80 more watts/m^2 of incident energy is arriving than in June. Because of the greater energy, the global average temperature should be about 3-4C warmer than in June. Instead, it's 3-4C colder. This is because of higher reflectivity of the N hemisphere due to the winter snow pack. This reduces the energy by enough to cause an effective 7C drop in surface temperature. If the northern snow pack was persistent, such as during ice ages, this difference would be a bias on the global temperature. When perihelion is in July, N hemisphere winters will be much colder and even though summers will be warmer, the colder winter could bootstrap the advance of ice. When the Earth's orbit is most elliptical and the Earth's tilt is maximum, there will be much larger seasonal differences, which in the past, has kicked off glaciation transitions.

No real glacial pack can accumulate outside of Antarctica in the S hemisphere since the snow belt is mostly over the ocean. This asymmetry, coupled with the asymmetry in the incident solar energy is the source of the apparent amplification seen in the ice cores. When the effects of solar variability rely on global averages, this asymmetry doesn't get modeled.
My point is that weather and seasonal effects are related to climate and can not be simply considered as a single average of the winter and summer.


reader Anonymous said...

What a fantastic blog - Thanks for sharing!
I have a layman's knowledge of the topic, but has been stricken by the almost complete lack of scientific consideration around global warming that seem more like mass hysteria than anything else.
A Norwegian professor, Atle Nesje, is doing interesting research, and I have seen a few others, but the masses seem mainly interested in jumping on the wagon, cashing in on research funding I suppose.

Keep it coming (not that I thought for a second you could be stopped), thanks!

reader Erik Bloem said...

I just wonder what happens to ocean seawater levels when in the next couple of 100's of years the oceans start to absorb CO2. Does this not change the density of the water? And if so, does the sea level rise just because of this, thus without changing the amount of land-ice?

reader Luboš Motl said...

Dear Erik,

no, the change of the H2O density after being enriched by some CO2 is completely negligible.

The mass of the whole Earth's atmosphere is 5 quadrillion tons, which is like the mass of 5 quadrillion = 5 x 10^{12} cubed meters of water.

The surface of the Earth is 510 x 10^{12} squared meters, so the whole atmosphere weighs like a 1-centimeter layer of water around the surface.

CO2 is only 500 parts per million of mass of the atmosphere, so it's five microns of water for all oceans (and only a small part of it is added by humans every decade). It is efficiently dissolved in water, so be sure that you won't see any dissolved CO2 on the sea level.

The sea levels currently rise by 3 mm/year or so. About half of it is from melting glaciers located on land (melting sea ice doesn't change the sea level at all, by the Archimedes' law), and the other half is from the thermal expansion of the oceans. Both of these effects arise from the temperature changes (warming) somewhere.

(But they're negligible compared to the history - 10,000 years ago, the rate of sea level rise was about 10 times faster.)

The changing chemistry has no direct effect on the density, except for undetectably tiny contributions comparable to the fractions of the micron per century. Chemistry only influences sea levels via temperature - but there are several other important drivers changing temperature, too.

By the way, in a few centuries, the oceans will absorb (or emited, in other eras) the excessive (or missing) gases from (to) the atmosphere. After millennia, the carbon and other elements may also drop to the deep oceans whose capacity to store such compounds is something like 100 times bigger than the upper layers.

So after these time scales, all the additional effects like CO2 added by humans will completely disappear, as far as all their observable effects go. That includes the greenhouse effect, so whatever greenhouse effect we're causing today will be undone in a few centuries (at most those 800 years or so), too.

Best wishes

reader Erik Bloem said...

"(But they're negligible compared to the history - 10,000 years ago, the rate of sea level rise was about 10 times faster.)"
True, it was even more than 10 times faster about 16,000 years ago...

"...and the other half is from the thermal expansion of the oceans."
If so, what amount of sea-level rise will thermal expansion contribute, by say, 1 degree rise of ocean temperature?

Oh, and by the way, don't get me wrong here, I agree with most of your story, especially that temperature is most probably the driving force and not CO2 in the past. I just go a little further in trying to understand other effects, and not stick in dogmatic thinking, but try to understand more of the whole complex system...

reader Luboš Motl said...

Dear Erik, it's always good to understand things more deeply.

I think that the current warming/sea_level trend ratio is representative of the underlying laws. In the last 30 years, we have 0.14 deg C of warming per decade, and 3 cm of sea level rise per decade. Multiply it by seven to see that one degree of warming gives you about 21 cm of sea level rise.

One could try to make a more accurate calculation, by looking at the actual internal mechanisms (instead of looking at the actual behavior, which is what I did), but that's what the IPCC has done and their precision is not spectacular, anyway. I think that these estimates are all about OK, and I won't tell you any figure that is much more accurate than that.

Again, when there were many ice sheets over the continents, the sea level rise per one degree of warming was much bigger, of course. There was much more water to melt. On the other hand, the thermal expansion of the oceans contributes roughly the same thing per 1 deg C of warming, regardless of the ice sheet volumes. It just happens that today, the two components are comparable.

Best wishes

reader Unknown said...

Thanks, Lumo, so I guess that it is ok to say that the max. sea-level rise will be around 20 cm in 100 years if average temperatures rise with 1 degree.

Since the latter is completely wishfull thinking and something we do not know (could also be more, but could also going down), it is, I guess, not possible to predict the future, we can only have what-if scenarios.

But thanks for the explanation. We shoul d all continue to think and look at all scenarios, still I think there is a small chance the alarmists have a point, since in theory (lab) higher CO2-levels result in higher temperatures, but the whole earth system and interaction with space is so complex that at least you can state that they have very, very thin ice to go on, and that your explanation even show that the probability that they are wrong is pretty high.

What I find most astonishing is that they always claim that there is proof. Well, I my conclusion is that that must be a lie.

reader Unknown said...

oh, Lumo, once more and changing subject a bit, but very relevant to the whole greenhouse discussion.

Yesterday on Dutch television they said that researchers had new data from Tasmania showing that between 30-50 million years ago seawater temp. were about 15 degrees, much higher than today. They also said that Tasmania was 50 million years ago situated close to antarctica. This would proof, according to these so-called scientists that CO2 can thus have a much higher effect than previously thought and thus that the greenhouse effect is much stronger than previously thought.

In my opinion they are probably right about the data, and also that Tasmania was located close to antarctica, but think that the conclusion is wrong, at least there are other, much more logical , explanations for the data.

A few years ago I read an article in Nature from geologists claiming that melting ice from antarctica isn't that simple at all. They said that 60 million years ago antarctica was connected to Africa and South America and that thus all ocean currents were different then today. Today antarctica is surrounded by ocean and there is a strong ocean current going around antarctica, driven by the rotation of the earth. Since in the past there was partly continent this current could not exist. Because of this current, warm water from the equator can not reach the cold waters of antarctica because it can't pass the current. This means that it is not easy to heat up the waters and the position of the continents contribute to the relatively low temperatures on earth since the continents broke up.

To my opinion this is a pretty logical idea, and that would also explain the findings of the relatively high temperatures found on Tasmania, since 50 million years ago waters from the equator could easily reach Antartica and Tasmania. So their conclusion that it was due to CO2 levels sounds to me as another tunnel vision. What do you think? Maybe it is worth another blog?

reader Unknown said...

Lumo, sorry, I am logged in on my mum's account, the comments I just posted today (one about comment on my earlier one and the one on the ocean currents) are from the same Erik as the last posts...

cheers, Erik

reader Luboš Motl said...

Dear Erik, those things with Tasmania are interesting but one would have to carefully look at the 1) position of the place and/or surface of the sea millions of years ago - which changed by continental drift, and 2) the actual temperature.

At any rate, whatever the temperature was, it is very clear that CO2 couldn't have been a cause of a warming comparable to 10 deg C. The bare greenhouse effect corresponding to CO2 doubling is 1.2 °C, and it is almost certainly even smaller when feedbacks are included.

10 deg C corresponds to 8 times 1.2 deg C, which would mean 8 CO2 doublings, which means multiplication of CO2 by 256 - an impossible change in recent millions of years.

Moreover, it's known from the Vostok data etc. that the temperature had to change because of other reasons than the greenhouse gases because the gases followed.

I would have to see what they exactly claimed and what evidence they were using but what you write sounds like an excessively shortened sequence of logical arguments.

Best wishes

reader Koeny said...

I'm completely with this article but one comment: the 0,7°C warming was global and the 8°C warming during the Pleistocene interglacials was measured by analyzing ice cores and were confined to the ice core sites.

reader Erik Bloem said...

Dear Lumo,

about the position of the continent they are right: Tasmania and Antarctica were positioned near the South Pole that time (Tasmania moved, Antarctica not much...). But according to me they did not think about the changed global ocean currents, which changed because of the different position of all the other continents except Antarctica (see Pangea for this). According to geo-scientists in Nature this changed the climate near Antarctica dramatically, which is a much beter explanation than that this climate change was caused by a change in CO2...

reader John Fitzgerald said...

I sure would like to know where the data came from. I downloaded the Vostok Data when it was still on the Vostok server.

I'm looking at it and the CO2 concentration peaks are ahead of the temperature peaks by about 2000 BP. Of course, you can't 1) eyeball correlation 2) pick some arbitrary subset of the data.

It will take some time to get to the core data used by the authors.

I always start from the basic facts. The basics is that the recent historical data demonstrates warming which is substantial since the 1970's. This is the fundamental concern. Whatever the Vostok data indicates, doesn't change this concern and without this concern, the Vostok data is just some other exercise.

Now, the referenced paper synopsis states "the timing of changes in these gases with respect to temperature is not accurately known because of uncertainty in the
gas age–ice age difference."

Great, so this author can't make a connection.

This is then followed by "suggests that the CO2 increase lagged" which just strikes me as odd to follow "not accurately known" with a definitive statement.

The opening paragraph includes "The gas age–ice age difference (+/-age) may be uncertain by 1000 years or more". While the synopsis says, "CO2 increase lagged Antarctic deglacial warming by 800 +/- 200 years" He seems to get from +/- 1000 years error to +/- 200 years error.

The paper then simply tells me nothing about the relationship between CO2 and temp as it applies to the current warming trend.

All I get is, at worse, the paper suggests that the Vostok data isn't shedding sufficient light on the current issue. At best, it is suggesting there is more complexity in the dynamics.

The blog, though, seems to misrepresent the paper in an attempt to find "proof" that AWG is incorrect. And, it fails to return to the original basis of the issue, the current warming trend.

There is an important point to consider. The Vostok data examines non anthropological dynamics. The current problem is anthropological dynamics.

If, indeed, the Vostok data indicates that CO2 leads temp in the millenniums of the earth history, this might provide a clue as to the current issue. If it fails to indicate this correlation, it just doesn't provide a clue. If it actually demonstrated that the non-anthropological effects lagged, then we would be left with "I don't know".

We would be left with "I don't know" because we are hoping to infer the current anthropological dynamics from non-anthropological dynamics.

There are three ways to delineate the answer to a question. "Yes", "no", and "I don't know".

"I don't know" doesn't infer "no".

Not much help dude. Thanks for a rather extensive article that concluded nothing while inferring that "I don't know" is the opposite of "yes". Great, I really needed to read another article going into deep detail about how someone doesn't know something.

Now, perhaps we might get back to the fundamental issue. What are the causes and effects of the current AWG?

It seem that, from current data of the current AWG trend is still that CO2 is the causal effect.

Note: the blog is also peppered with numerous logical fallacies. Logical fallacies are, at best, just a way to fill up space so that the article meets his 1000 word quota, or whatever. They distract from being direct in achieving the goal of providing useful information. And they indicate a though process that is busy following useless connections.

reader John Fitzgerald said...

I'm annoyed. I read to learn. In the process, I find articles filled with distractions, non sequiturs, logical fallacies of every type. The whole process of attempting to understand AWG has become a study of logical fallacies rather than what it should be, an honest and direct examination of the science.

I find this disrespectful to the reader. Science is hard enough to grasp without the distractions. Logical and good intelligent thinking takes effort.

What I am never quite sure of if this writing which peppers it's article with non sequiturs is disingenuous, author ego stroking, or simply sloppy thinking. Either way, what it does tell me is that I cannot trust the writer to have my interests as a reader in mind. Whatever his intent, his writing serves his own self interest at the expense of mine.

So I don't buy it. I don't by it for a number of reasons. One is that I have to first identify and extract all the bs before I can begin to examine the facts. A second is that, given the excessive tendency towards obvious use of logical fallacies, I am even less willing to trust the honest presentation of the facts. The third is that I cannot begin to trust his conclusions.

But thanks for a couple of links to honest research papers. I'll be sure to give them the effort that they deserve.

reader Erik Bloem said...


the basic facts are that climate always changes, and that the changes of the last 40 years are not at all extraordenary, on the contrary. So there is no way that the basic facts tell us anything about human influence. For example, sealevel rise about 16000 years ago was around 4 meters per 100 years, last 100 years a couple of cm's...

In addition, I don't think you understand the impact of temperature being leading in the process... You state that the paper misinterpret the data. Where? If you just look at the data, the conclusion is not correct to state that CO2 leads temperature, better is to state the opposite.

At least there is no proof that CO2 caused temperature rise in the past! And that is important. Also, this article explains that the AWG adepts don't have an explanation for the extreme rise in CO2 in the past, for temperature rise with consequent degassing the explanation is much easier.

So AWG leaves us with big unsolved questions, and they come with the statement it has been proven. So your statement about 'yes', 'no' and 'I don't know', is simply the other way around. AWG adept can't state they are sure, there is simply no proof. That rising CO2 levels lead to higher temperatures can't be answered with a 'yes', but should be answered with 'I don't know'...

reader Werner Brozek said...

Reader Peter, Feb 28, 2008.
I have what you are looking for:
The following web site seems to suggest carbon dioxide plays virtually no additional role:
After analyzing the data and noticing very little difference due to CO2, this web site has the following quote:
"This may especially be the case if there is any overlap between the absorption bands of water vapor and CO2. In this scenario, because all the energy in the bands is absorbed, further increases in CO2 will have no additional greenhouse effect. The implication would be that the pre-industrial concentrations of atmospheric CO2 were already close to saturation
(total absorption) levels."

Werner Brozek
Science teacher

reader Shelly said...

This is one of the best blogs I have read on the "debate" --although as we have been told, "the Debate is over."

I spoke just yesterday to a women who teaches internet courses on the climate changes we are experiencing (University of Alaska)--she said the evidence was overwhelming that the earth is warming and that catastrophic changes in weather will wipe out whole species (ex. that the caribou arrived in their feeding grounds at the right time to eat nutritious new buds, but global warming was the cause of the buds blooming two weeks early and the caribou didn't get the nutrition they needed and had weakened immune systems=global warming, nasty humans). She claimed that most global climate changes occur slowly but that we humans accelerated it with our CO2 emissions and will wipe out lots of animals and therefore have to stop our evil ways.

I pointed out that many climatic changes are very quick--such as the frozen mammoth found with daises in its mouth. "She never heard of that!

I asked her why Mars was also warming along with with the earth. She never heard of that.

I mentioned Volcanoes emissions and thank God, she had heard of that-BUT that doesn't explain the last fifty years.

She diverted the conversation and said all the media were in cohoots with the oil people and weren't showing the "tons" of proof.

This is an educated women, mind you that I was talking to.

I pointed out that most of the media was on her side actually supporting the global warming changes--and she had to admit it was Fox she was talking about. she then continued to tell me how Fox never reported the truth. They had been sued by a women reporter who wrote about bovine hormones and Fox didn't want to to report the story she wrote. Fox won the suit-- "But only becasue," this woman teacher retorted, "there is no law that says you have to tell the truth."

In her mind this meant Fox doesn't tell the truth!

I seguewayed her back on topic by referring her to the suit brought by scientists in Briton over the Al Gore movie--that the scientists didn't want this movie to be shown in public schools as "real" science--the scientists won---she never heard of the suit!!!!!

I will send her this fabulous blog becasue it presents both sides with facts--not politics. I cannot believe that people like her are passionate about global warming and the evil oil companies (which of course Fox is a mouthpiece for)--and they TEACH in our universities--she never heard of the mammoths--other planets warming, and the suits against the Gore propaganda and she is telling our students what is "factual." HELP

reader Lucas said...

This is a great blog being able to communicate with educated people with different view and ideas.
personally i have been through propaganda and brainwashing, and i can see it when it is being done. And Global Warming is one of those things. The science of Global Warming is based on miniscule proof that states CO2 absorves low wavelength of energy and releases it in every direction. This does happen. But if we look on the grand scale, how much CO2 is in our atmosphere to cause this reaction? Not much, CO2 is measured in ppm. And according to current data, the CO2 level has gone way off the charts while the temperature stayed the same, this showed that CO2 is not the independant factor. Graph: With this, the fundamental basis of Global Warming is debunked, with legetament data.
I tried to persuade my Father, who does reasearch on atmosheric temperature, he doesn't believe me because of his strong belief in the proof of the greenhouse effect. This deny of idea occured with many people i talked to. This whole idea of Global Warming has gone beyong science, more like religion.

reader Lucas said...

An interesting thing about this subject is that the researchers are actually starting to find that the global warming that the media is protraying does not give the right image. The media says that CO2 is the big thing and the rising of it will contribute to the Climate's warming, however, in the past 7 years, no trends of warming have been recorded. The antartic gained ice cover. Although the arctic did warm up, the media is only showing that area, however globally the temperature has shown no trend of warming. (These information is obtained at a lecture at the Universtiy of Waterloo) However the CO2 level is increasing, but that does not mean a definate warming. Top scientists in this area of reaserch has tried to file a paper to the public, but IPCC has blocked this paper because of it constrasting views with the media. This will have a dramatic effect on the people's idea of climate when temperature falls in the next few years, causing everyone to be unenviornmentally friendly.

reader fraddict said...

About the article: in a cubic meter goes 1 BILLION cubic millimeters. Not just 1 million!

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reader Peter Osborne said...

Green plants and blue-green algae take the CO2 , release the oxygen, make their structures from the carbon. The more CO2 in the atmosphere, the faster they grow and the more plentiful they become. At the end of the ast glacial period , CO2

reader Voodude said...

I apologize for the low-res pics, in advance. Here we have some ocean, near the Kamchatka Peninsula, and off of Japan. The ARGO floats have told us that this area of the ocean is WARMING.

NASA's new satellite, the Orbiting Carbon Observatory, has shown us images of carbon dioxide...

It appears as if the warming ocean is emitting carbon dioxide.

reader Luboš Motl said...

Good if you observed it for the first time, and of course that it is true. People know it from hot summer day when a Coca Cola can tends to explode with all the CO2 because a warmer liquid isn't able to dissolve the same CO2 equally easily. It just releases it.

It's the same mechanism that guarantees the correlation of temperature with the CO2 (and methane and other gases) in the glaciation cycles. Temperature goes up, the ocean releases CO2, temperature goes down, the ocean absorbs CO2 from the atmosphere.

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