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Carbon dioxide & 800-year lag behind temperature

How alarmists think

As we have explained in 2006, Vostok ice core records show that the carbon dioxide concentration averaged over a few centuries has been correlated with temperature at least for half a million of years. However, we know for sure that the temperature was the cause and the CO2 concentration was its consequence, not the other way around. It follows that the greenhouse effect hasn't been important in the last half a million of years.

There are many ways to see it. The 800-year lag is the most popular one, it has been featured in the Global Warming Swindle (especially in this two-minute-long segment), and we will discuss it below. However, there are other ways to see that the influence of temperature on the concentration of gases has been more important than any influence in the opposite direction. For example, the ice core records show that the concentration of methane was correlated with temperature, too. If the CO2 concentration were the primary cause, we would have no explanation why the CH4 concentration was also correlated. In fact, CO2 and CH4 play the very same role in the ice core records. If some combination of them determined the temperature, we would still have no explanation why these two concentrations were correlated with one another.

Moreover, easy reasoning can be used to show that the ability of oceans to store gases decreases with increasing temperature and this effect is clearly much stronger than the greenhouse effect.

The 800-year lag

However, the most popular - and the most straightforward - explanation of the direction of the causal relationship is the fact that in all cases, the CO2 concentration only changed its trend roughly 800 years after temperature had done the same thing. There have been many papers that showed this fact and incidentally, no one seems to disagree with it. For example, a recent paper by Lowell Stott et al. in Science (2007) showed that 19,000 ago, when the last ice age started to go away, CO2 lagged by about 1,000 years, too.

Every sane person knows that this detailed insight implies that the greenhouse effect couldn't have been among the most important effects. Not only the ice core data fails to provide us with evidence supporting the greenhouse theory of the climate; it provides us with strong evidence against it.

The greenhouse effect has been much less important than outgassing. Although we add more CO2 than what Earth has seen for millions of years, the small characteristic importance of the greenhouse effect probably wins.

For whatever reason, some people are not willing to accept this obvious conclusion. That's why they invent various bizarre verbal constructs to circumvent the otherwise inevitable conclusion. The whole "group" at RealClimate.ORG has agreed that there was a lag. But they say that in the first 800 years when the influence of temperature on CO2 is manifest, it was indeed temperature that drove the gases. But in the remaining 4200 years of the trend, it was surely the other way around: CO2 escalated the warming, they say.

Everyone who has basic understanding of feedback theory knows that what they talk about is a textbook example of a positive-feedback system, and if the climate were such a system, the mutually supportive interactions would lead to exponentially escalating temperatures in one of the possible directions. That's clearly not observed in the data and the positive-feedback hypothesis is thus falsified.

The list of people who understand basics of feedback theory includes Jeff who would like to believe the RealClimate.ORG guys except that he has found their rebuttal "incredibly lame, and, in [his] opinion, plain wrong." So he gave a detailed, technical version of my argument above. He also concluded that the hypothesis that CO2 actually helps to regulate the temperature is much more consistent with the data and he asked the owner of an alarmist blog called Reasic what's the answer and whether there is some other evidence for the greenhouse-driven theory of the climate that could replace this obviously wrong argument based on the ice core correlations.

Reasic answers

What answer did he get? Reasic first mentions several rudimentary facts about the greenhouse effect and what kind of electromagnetic radiation it affects. These comments have clearly nothing to do with the direction of the causal relationship in the ice core records and with Jeff's rather sophisticated concerns. Reasic nevertheless adds a paragraph about the absence of any doubts. In my opinion, there can be no doubts that the reader who would think that the relevance of the greenhouse effect has been proven in this particular Reasic's paragraph should see her doctor.

But it gets even better. Reasic tries to answer the first paragraph that talks about the 800-year lag. The alarmist blog says:

  • The idea that this lag somehow debunks the theory of anthropogenic global warming did not originate from the scientists who discovered the lag. It has come from right-wing pundits and skeptics.

Very relevant argument. I am sure that Jeff will be impressed. :-) This kind of "argument" could be good enough for something in between orangutans and chimpanzees. How does Reasic support the statement? Well, the website tells us that the paper that reported the lag contained the following sentence:

  • ... is still in full agreement with the idea that CO2 plays, through its greenhouse effect, a key role in amplifying the initial orbital forcing ...

You have heard the holy word. Well, what Reasic fails to grasp is that science - including experiments, calculations, and arguments - must be reproducible. If an argument can be shown to be manifestly wrong by a careful analysis now, it really doesn't matter whether it's written in one paper or two. Also, it doesn't matter whether the authors of a flawed assertion have previously made some experimental discoveries. These two things have nothing to do with each other. When the Bible used to determine the ultimate truth, the rules of the game may have been different. But times have changed.

Sorry, Reasic. This sentence of that paper is manifestly wrong and one could even speculate that it was added to satisfy politically biased reviewers or co-authors of the article that revealed rather strong evidence against the greenhouse theory of the climate.

Concerning Jeff's main comment about the unobserved positive feedback, Reasic says that he or she is no expert but he or she answers anyway:

  • First, some unknown event triggers the warming (and there are several theories on what this event is).

Maybe it's Gaia. At any rate, the main observed features of the graphs and their causes are not what the politically correct people interested in the climate should look at. They should look at the featureless parts of the graphs :-) that carry no information but where Gaia can conveniently hide with all of Her theories and all of Her prophets and their disciples.

  • Then, the warming triggers a mixing of the deep ocean, which releases CO2 (a process known as “outgassing”).

Well, if warming of the middle troposphere directly triggers motion in deep ocean, I suppose that this remarkable synchronization was organized by cell phones. ;-) But note that Reasic can spell "outgassing": that's really impressive!

  • There is a finite amount of CO2 in the deep ocean, so CO2 cannot be released into the atmosphere indefinitely.

This is another really cute comment. Most kids in the kindergarden will agree with me that there is much more material in the ocean than in the atmosphere. Air is the light substance inside the bubbles from bubbly fu*k - how do I translate this Czech word into English? - while water is heavy. And some of the most educated kids will even know that the oceans contain 50 times more CO2 than the atmosphere. Search for 50 times at this page.

The idea that their hypothetical positive-feedback instability would stop growing because the ocean runs out of CO2 is really entertaining. It's like a very fat woman on a diet who has 50 cakes in her (rotating) fridge and who simply loves to eat cakes. The more she eats, the more she loves it. But after she eats one half of the first cake, she decides that she is running out of cakes and stops. While it's completely silly, Reasic offers us several more sentences with the very same content:

  • Also, it is believed that the 800-year period is also the mixing time for the deep ocean, further solidifying this theory. So, there is a limit to the amount of natural CO2 that can be released, making a never-ending cycle of temperature increase unlikely.

And some of the alarmist readers are grateful for these great arguments! Well, one person's waste is another person's cake.

And that's the memo.

P.S.: Eric Steig has created another meaningless text composed of lies and fog about this topic. Unlike others, he even wants to question the fact that the lag is there. Instead, he argues that CO2 "leads" the temperature variations on "historical "timescales. I am pretty sure that he must realize that what he writes is a downright lie. There doesn't exist a single example of a correlation between CO2 concentration and temperature in which CO2 would "lead" temperature. Such an opposite relationship didn't occur in the glacials and interglacials and it was not a part of the modern history either. The modern, post-little-ice-age warming started well before significant emissions of CO2. I wonder how stupid the people who buy these obvious lies must be. The people who spread these lies - like Eric Steig - are criminals who should be arrested before it's too late.

Bonus climate articles on The Reference Frame

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snail feedback (9) :

reader Bruce Hall said...

Dr. Tim Patterson of Carleton University in Ottawa presented this subject very well.


reader Mark said...

"Everyone who has basic understanding of feedback theory knows that what they talk about is a textbook example of a positive-feedback system, and if the climate were such a system, the mutually supportive interactions would lead to exponentially escalating temperatures in one of the possible directions."

The energy emitted by the earth as black body radiation increases as the fourth power of the absolute temperature of the earth. This places a limit on the feedback, because this radiative loss overcomes the increased forcing (which increases only logarithmically with CO2) from more CO2. As the temperature rises & CO2 is going up, the energy radiated increases even faster, allowing a new equilibrium to be reached, rather than becoming an unstable positive feedback loop.

Still, it's not strong evidence for AGW, as Al Gore presented it to be. You have to look elsewhere for that. Frankly, Al Gore was stupid to use this chart in the simplistic way he did.

reader That guy with the top hat said...

I'm no expert or anything, but doesn't the ocean create a lag?

I mean, in the ice cores, when they are measuring temperature, they are measuring temperature at the time that the ice was frozen. When they measure carbon dioxide, they measure the amount in the water at the time the ice was frozen, as it's pretty much impossible to measure the atmospheric CO2.

If the oceans absorb C02, and there is a lag in the oceans, doesn't that mean that after the lag, there would be more C02 in the rain water?

Like I said, I'm no expert, but this is just common sense to me.

I don't know what math to use, but couldn't this account for the "lag" in C02? It seams to me that that increased temperature would take a lot longer to increase the C02 than the other way around, since the greenhouse effect can be replicated in a lab.

reader Luboš Motl said...

Dear wtf, the ocean creates the lag but not in the way you think.

When the ice freezes, the newest layer exactly stores the information about the environment in the same year. CO2 is directly included in the bubbles. CO2 is not included in the rain - rain is more or less pure water - CO2 is in the atmosphere around it.

Also, the temperature is directly reflected to a concentration of an isotope. You can't create 800-year lags in this way. The observed lags are real.

Moreover, there are other - in my opinion even more solid - ways to see that the temperature is the cause and the concentration of gases are its consequences. For example, not just CO2 but other gases also copy the evolution of temperature.

If CO2 or CH4 or a specific combination of theirs were the driver, you couldn't explain why CO2 and CH4 are correlated with each other. Just to be sure, CH4 is also lagging.

reader Dan said...

You have so many factual and logical inaccuracies in your original post, that I wouldn't even know where to begin if I was going to address the whole thing. The only part I feel your readers need to know is your fat lady analogy is dead wrong. The ocean does contain 50 times more CO2 than the atmosphere. But that doesn't mean that the oceans wouldn't stop degassing until the two are at a 1:1 ratio. The carbon in the ocean is set by the saturation state of water vs. air. Water can hold more. But it is a linear relationship. If there is 1 CO2 molecule in the atmosphere, there will be 50 in the ocean. If there is 10 in the atmosphere there will be 59 in the ocean. Now, if there is 59 in the ocean because it equilibrated with an atmosphere that has 10, but then it is exposed to an atmosphere with 1 (as it upwells), it will equilibrate back down to 50. Then it stops. There is no more carbon added to the atmosphere. There is still 50 times more carbon in the ocean than the atmosphere, but it is back in equilibrium. Your previous statement that a positive feedback will show an exponential growth in one direction is absolutely correct. I challenge anyone to look at the warming coming out of the last glacial and tell me it doesn't look like an exponential that got truncated because one of the feedbacks stopped. And if you can say that, then you need to look up the definition of exponential and see what the curve really looks like. Now, if you accept that this is a feedback that is led by temperature, that means you accept that CO2 does increase temperature. Does it matter which starts first, if we add more CO2 that would not be there naturally then you increase the feedback and it doesn't stop as fast. The 800 year lag does not affect whether or not CO2 has an affect on global temperature. It only tells us that the trigger for the warming in the last deglaciation was something else.

reader Luboš Motl said...

Dan, what you are writing sounds as a new kind of religion. I am not sure whether you are joking or not.

Your counting of carbon equilibrium is complete rubbish. At very long time scales, one restores Henry's law - there is a special article about this topic on this blog - in which the ratio is fixed.

So increasing a gas from 50 to 60 in the ocean corresponds to the increase from 1 to 1.16, not 11, in the atmosphere. Please think again. Find "Henry's law" and think about it. At shorter time scales, Henry's law is violated and the deep ocean is not accessible because it takes time for the gases to penetrate.

But the fact that the ocean contains much more carbon than the atmosphere of course DOES mean that if you wait for a long enough time, it will absorb the carbon from the atmosphere. No sane scientist doubts that after a few centuries after we stop adding CO2 to the atmosphere, the atmospheric concentration drops to pretty much the "pre-industrial" value.

This is a completely rudimentary exercise. The capacity of the ocean is effectively infinite in the long run and it is only smaller in the short run because only the upper ocean can absorb quickly and it gets saturated more quickly.

But your comment about the instability is even more stupid. You say that the exponential was truncated because "one of the feedbacks stopped". How did it exactly happen, did the laws of nature suddenly change? Or did God save the planet from the rest of the exponential curve?

Physical laws can't suddenly "stop" to work. Sorry but this particular comment of yours was so incredibly stupid that I will probably protect the blog against further spam from you.

reader Dan said...

First off, if you cut off the supply of CO2 to the atmosphere, because they have reached a new equilibrium, then that stops the feedback. You don't have to invoke any new age physics for that. A positive feedback cycle cannot continue if there is only one side of the feedback operating. If you don't add any new carbon dioxide, the exponential increase stops.
As for the Henry's law thing, you are correct, I oversimplified for the sake of people who don't understand gas partial pressures. But the point stays the same, the ocean would not dump all of its carbon into the atmosphere. You said it yourself, the capacity of the ocean is essentially limitless, but it has to remain in equilibrium. And as you said, deep oceans can be out of equilibrium temporarily due to the fact that they are out of contact with the atmosphere. But when they come back up, they only degas until they have reached equilibrium and then the stop.
You are absolutely dead right that the ocean will absorb all of the carbon that we put into the atmosphere over the next couple centuries. But unfortunately, neither you nor I will live long enough to see this happen, so we will have to deal with the climate in the transition.

reader PatentedGooner said...

I'm not sure how a feedback explains the lag? If CO2 lags the Temp then isn't that pretty conclusive that temp is driving atmospheric CO2? Further, what activities were driving the previous "cyclic" rises and declines in CO2 before human activity.

I know these are basic questions, but ones Mr. Gore should have spent more time on rather than pandering for emotions by showing polar bears, destroyed houses and Katrina victims.

Also, can anyone point to a good article (scientific, not journalistic, please) illustrating the volume of CO2 from human activity vs. the CO2 from the "feedback" outgassing of the oceans. Is it feasible that Kyoto (and the like) will even help?

reader Lord Poo said...

patentedgooner, I'm no expert either, but in the past temperature has caused CO2 concentrations to go up (as explained in that guy's post) but now humans are releasing CO2 into the atmosphere because of the large amount of factories :-(

Also, I believe it's the Milankovitch cycles that cause the 100,000 year ice age cycles and also brings us out of them, with some help from greenhouse gasses and other factors.

Read more about the Milankovitch cycles on Wikipedia.

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