Warming in a global cool period
By Peter N. Spotts| Staff Writer for The Christian Science Monitor/ September 25, 2008 edition
Graph above added by Anthony – not part of original article
With all the focus on human-triggered global warming, it may be hard to imagine that the world is riding a 50-million-year-long cooling trend.
But it is, and blame the trend on a continental-scale collision, say geophysicists Dennis Kent of Rutgers University and Giovanni Muttoni of the University of Milan in Italy.
Researchers say there is strong evidence that increases in atmospheric CO2 contributed to a warm spell 50 million years ago dubbed the Early Eocene climate optimum – the warmest period in 65 million years. But over the following 15 million years, deep sea temperatures fell by about 10.8 degrees F., reflecting a significant cooling at the surface. This cooling ultimately allowed the cycle of ice ages to emerge.
Drs. Kent and Muttoni have mined paleomagnetic and other data and suggest that atmospheric CO2 dropped because India collided with Eurasia, shutting down a productive, natural CO2 factory.
Some 120 million years ago, the subcontinent that is now India was migrating north from Antarctica. As it moved, it shoved the ocean crust that was ahead of it under an existing crustal plate. As long as this zone off the Eurasian coast was under water, bottom muck enriched by carbon from the biologically-rich ocean plunged under the plate. It got recycled as lava in volcanoes along a geological feature dubbed the Kohistan Arc, as well as in a vast lava-oozing formation called the Deccan Traps. The eruptions released the carbon as CO2, which helped warm the climate. But once India collided with Eurasia 50 million years ago, India rode over the top of the zone and shut off the process. This, plus changes in ocean circulation as continents rearranged themselves, contributed to the long chill, the researchers suggest.
The results appear in the current issue of the Proceedings of the National Academy of Sciences.
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Mr. Norris-
Apparently sarcasm is beyond your comprehension. I’m sure most other people here can understand the use of absurdity, to demonstrate absurdity. I know Anthony has a sense of humor, at least.
Go ahead and ban me, if you want. I see no point in contributing here any more if humor is no longer permitted. And unless I’m making threats, it’s none of your business who I am. I expect you’d find that the addresses of MOST of your infrequent commenters are fake. I’ve used that address about once a week, for several months. No one ever said a word about it, until you showed you couldn’t understand an obvious joke.
If you’re looking to pick a fight with climate alarmist, perhaps you should actually find one.
REPLY: Ted the d-word as you applied to people present is not used here, sorry if you don’t like that, but it’s not negotiable. I also expect people to use real email addresses. Anonymous commentary while allowed, isn’t given the same weight as people that use their real names and have valid email adddresses. – Anthony
“Land and Oceans are absorbing 54% of this amount (2 ppm).”
I believe your Manifesto assigns 800 GTons of carbon as the size of the biogenic sink, primarily surface vegetation.
During the day this sink lays up CO2 and expels CO2 at night. Yet the daily fluctuation results in an increase at 20,000′ of 6ppm in CO2 over the evening measure.
This would lead one to reasonably conclude that the fluence between the ocean and atmosphere dominates. The temperature rises during the day, expelling CO2 and as the temperature drops during the evening the CO2 absorbed. Lets call that total 80 GTons. 1/10 of the entire biogenic sink, is entering and leaving the atmosphere daily!
Spencer’s post here showed that while the biogenic sink prefers to lay up 12C and expells !3C that the seasonal signal, supposed by Keeling biogenic, is not distinguishable from the trend, the sum of all fluences by its 13C/12C fraction.
Thus the ocean temperature determines the atmospheric abundance.
What do you propose to as evidence that your piddling 2ppm is anthropogenic? The fact that the Manifesto says it is so?
Gary, Land and Ocean daily and annual CO2 exchanges clearly dwarf human emissions.
The last numbers I have seen is that Land (plants) and Oceans absorb 154 GTs per year and emit 150 GTs. This is compared to human emissions of 8.5 GTs per year.
But we are adding Carbon to a system which was more-or-less balanced to start with. There is no point arguing humans are not contributing to the rise in CO2 concentrations when CO2 levels are increasing at 4 GTs per year (Carbon) and we are emitting 8.5 GTs per year.
And the theory regarding Oceans absorbing Carbon is that cooler Oceans will absorb more and warmer Oceans will absorb less (emit more). If warming Oceans are responsible for all the CO2 increase, then global warming is real because rising Ocean temps are one of the things which should happen with global warming.
Given that Ocean temps have not warmed over the last 4 years according to the best estimates, CO2 levels should have stabilized over the past four years if human emissions were not a contributing factor.
Obviously, Ocean conditions and plant growth on Land are affecting the annual numbers . CO2 numbers jumped during the 1998 El Nino, for example. But we are adding 8.5 GTs per year to a system which was/is sinking 4.0 GTs per year on average so the net numbers are increasing.
I think this is generally a good thing. That natural processes are taking in so much of what we are emitting. Maybe the natural processes, especially plants, will even accelerate and take more CO2 in. Then there will be nothing to worry about. No global warming and higher plant growth.
We don’t even know the temperature 150 years ago. Look at the weather stations. We certainly can’t trust a 50 million year guess.
Dan Lee: “That whole thing falls apart when either of the following are shown to be true: (1) there was more warmth in the past; (which didn’t trigger any positive feedback b/n CO2 and water vapor), (2) there was more CO2 in the past (which didn’t trigger any positive feedback either.) …Are we giving them life by not shining the spotlight more on the core of their argument?”
It really helps to have a grasp of the big figures, to show just how pifflingly small is the human contribution, and how much evidence there is for living processes involved in maintaining homeostasis. But finding the figures and the science… they are scattered here like gold dust… and sometimes they seem questionable… for instance…
Gary Gulrud, you said “Daily variance of CO2 measured by AIRS in mid-troposphere and at 10,000? at Mauna Loa is on the order of 10^1 ppm, this corresponds to a daily fluence between ocean and atmosphere of on the order of 100 Gtons!”
But my calculations go thus: 380ppm CO2 in the air… http://www.grida.no/publications/vg/climate/page/3066.aspx shows a total atmopsheric CO2 weight of c. 750Gt. Maths: 380ppm=750Gt, thus 1ppm=~2Gt. Therefore you figure of 10ppm corresponds to 20Gt.
I’ve put the figures as best I could, graphically, on my primer (link thru name). These figures were taken from places like Glassman’s and Anthoni’s websites, both of whom I have a high regard for, science-wise. But they are not infallible either. ALL CORRECTIONS WELCOME!
Joel Shore says:
“I think that the idea that the two of you are missing is that different processes can dominate on different timescales. A given major volcanic eruption releases lots of particulates and not all that much CO2. However, the particulates wash out of the atmosphere relatively quickly (generally within days when they are ejected only into the troposphere and within months to a few years when they are ejected into the stratosphere). CO2, by contrast, stays in the atmosphere a long time.”
The problem with that, Joel, is that all the actual evidence (as opposed to ad hoc theories created to support long lifetimes) shows that CO2 has a relatively short atmospheric lifetime. See, for example, the measured lifetime of radioactive CO2 after the 1964 atmospheric nuclear test ban took effect: http://cdiac.ornl.gov/trends/co2/well-gr.html
Up until about 20 years ago, it was considered an established fact that CO2 had a 5-10 year lifetime in the atmosphere, established by a number of means. (See, for example, this short discussion:: http://www.financialpost.com/story.html?id=433b593b-6637-4a42-970b-bdef8947fa4e)
Now, however, that would be a truly “inconvient truth”, as it would directly imply that Human-created CO2 (being created over 100 years) could only account for a few percent of the observed rise in concentration. Hence it has become necessary to promote, with a straight face, complicated theories, unsupported by any actual measurements, that “prove” a long lifetime for CO2. In general, those who promote these theories don’t attempt to explain what is wrong with the actual measurements of decades ago — they simply ignore them.
@Bob Cormack:
Didn’t you know that Gaia can selectively extract the radioactive CO2 from the atmosphere to help restore her natural balance? And that she is causing her mighty oceans to inject CO2 into the atmosphere just to rid herself of humanity who has spoiled her pristine environment?
Gosh, you must be expecting proven physics and chemistry to rule. 😉
Joel Shore: Let’s say that for every 1 deg rise we cause in the temperature due to the direct effects of increasing CO2 levels…
I’ll bet you thought you could sneak that one by. Nice try. Firstly, our contribution of C02 is small, only about 3% or so. Secondly, C02’s warming effect is logarithmic; by far, most of the limited warming effect (small, in comparison to water vapor) has already occurred.
Joel, in your response to Dan Lee, you admirably try to give sensible reasons for addressing CO2 emissions, unlike Al Gore and others who–believe it or not–do talk about catastrophes more serious than famine and world war in a time frame of 100 years or even less.
However, you talk right past Dan Lee’s much shorter argument.
Dan Lee says:
Finally, some perspective. An atmosphere that has remained stable enough to support the 3+ billion year evolution of life, through all these extremes, isn’t going suddenly spiral out-of-control into a life-baking oven when it hits 400 ppm of CO2.…If you take away atmospheric positive feedback, aren’t we done? End of show? Nothing left for AGW to stand on?
You wrote: “(1) No serious scientist that I know of is claiming that there is a Venus-like instability and the climate is going to “spiral out-of-control into a life-baking oven” once CO2 levels hit 400ppm. The positive feedbacks just magnify the warming due to CO2 alone…They are not strong enough to lead to an instability. (On Venus they could because it is closer to the sun and hence receives more W/m^2 of solar energy.)”
Joel, you are ignoring the broad point by discussing the details. This magnification you breeze by is what turns a 1-ish degree increase into a 5-ish one or more. Take a moment to really think about this. If a 1 degree increase was all we faced even at 5000 ppm of CO2, then that would take all the wind out of the sales of people saying we face doom if we don’t decrease CO2 emissions. Thus, the positive feedbacks are key. Do you care to address this, or dare I say, concede it?
Dee Norris: Are you saying that (gasp!) AGW is a religion?!
Now that you’ve brought it up, I have noticed a strange similarity between the few “conversations” I’ve had about this subject on less friendly sites than this one and the types of interactions I’ve had with missionaries at my door 😉
(Except perhaps that missionaries, lacking the cover of anonymity, tend to be more polite.)
@Bob Cormack:
Didn’t impolite missionaries end up in the stew pot?
Lucy, Bill: It is entirely credible that I’ve made an arithmetic error or used a value from the public domain inappropriately, but I believe this to be more likely than one of a logical/conceptual sort.
My recollection is that the accepted weight of atmospheric C02 was 3000 Gtons, the surface vegetation 800 Gtons, oceanic dissolved CO2 50,000 Gtons and oceanic precipitate CO2 100,000 Gtons. I’ve seen in comments here recently, someone imply an atmospheric weight comparable to the biogenic weight which I discounted as an implausible typo.
My impression is that the oceanic phytoplankton are tossed in to the oceanic dissolved total.
I make no claim to precision; one source of inaccuracy on my part is to ignore in the daily variance a moderately hydrophylic nature of CO2 carrying it aloft during the day as the temperature rises. I do that because the Mauna Loa daily variance is larger than the AIRS factor and not the inverse.
The central issue is that balanced equations, in the manner of chemical reactions, for the results of CO2 flux computations, are conceptually invalid predictin results. In chemistry we rigidly control inputs, solvent, temperature and pressure. This is not the case in nature in any way, shape, or form. They are valid only as a snap-shot of the present.
Establishing the origin of the CO2 empirically is required for the assertion that it is of antropogenic origin in any genuine expression of fact. This would at present, require use of the 13C/12C fraction. Seuss naively supposed that since the 13C was increasing that this proved anthropogenesis. Unfortunately, he was mistaken, having ignored the temperature dependent oceanic partial-pressure of CO2.
The inference that because total fluences of CO2 in nature are at any moment “in balance” therefore implies that a change composition of one sink or another can be assigned to a fluence of choice is false in principle and false in actuality. Truth and falsehood is not democratically resolved.
I grew up in Wisconsin and I want our glaciers back. A mere 12,000 years ago we had ice as thick as 5000 feet. Can you imagine the beer you could chill with that? I blame Al Gore for inventing global warming along with the Internet. To hell with all those paleoclimatologists and their interglacial periods. Never mind that we have gone through these cycles a couple of times before. I blame all those early Americans in North America back 12,000 years ago for driving all those SUVs.
Bob Cormack says:
The problem with that, Joel, is that all the actual evidence (as opposed to ad hoc theories created to support long lifetimes) shows that CO2 has a relatively short atmospheric lifetime. See, for example, the measured lifetime of radioactive CO2 after the 1964 atmospheric nuclear test ban took effect: http://cdiac.ornl.gov/trends/co2/well-gr.html
The problems with that graph are:
Bob
(1) It doesn’t address the question of interest…which is not how long it takes a particular carbon atom to cycle out of the atmosphere but how long it takes a perturbation in the total atmospheric level of CO2 to decay. They are different things.
(2) It is not obvious from that graph that the lifetime is what you claim it to be. As I noted, the decay of CO2 is simply not described well by a single lifetime…So, some fraction of a perturbation in the CO2 levels disappears quite quickly but there is also a long tail. Whether the long tail is there or not for what you have plotted can’t really be determined from what you showed.
Bruce Cobb says:
If you don’t want to be taken seriously by any real scientist, I strongly suggest that you continue to repeat the 3% nonsense.
As for its effect being logarithmic, what that means mathematically is that doubling the level from, say 280ppm to 560ppm will produce the same effect as doubling from 140ppm to 280ppm. (Your statement that most of its limited warming effect has already occurred is essentially incomprehensible. If you mean that the rise from 280ppm to 380ppm has already gotten you most of the warming from a doubling from 280ppm to 560ppm, you are demonstrably wrong…even neglecting the issues of the climate not having yet caught up to the current CO2 levels.)
Daublin says:
This is garbled to the point of incomprehensibility. You seem to be (among other things) confusing projections about future temperatures (which depend on how one assumes CO2 levels get) with estimates of the equilibrium climate sensitivity to a doubling of CO2. You are correct that in the absence of positive feedbacks, a doubling of CO2 should produce a bit over a 1 C temperature rise. However, raising CO2 to 5000ppm would be somewhere more than a 16X increase and would thus raise temperatures 4 C in the absence of feedbacks.
And, the IPCC range for the likely equilibrium climate sensitivity is 2 to 4.5 C, not 5 or more. At any rate, I agree that the positive feedbacks are important (at least if we don’t allow the CO2 levels to get too out of hand–if we let them get up to 5000ppm for example, then we are screwed with or without the feedbacks). However, you can’t just wish them away and the current understanding of the paleoclimate seems to require them being there. In the case of the water vapor feedback and the ice-albedo feedback, they also follow from some pretty basic physics…and the water vapor feedback has observational confirmation from the work of Soden et al. among others.
Lucy, I believe your site is using Carbon, or about 28% the weight of CO2.
750 Gtons C == 3000 Gtons CO2. Otherwise, the figures I quoted do vary somewhat from the estimates at the link.
“If you don’t want to be taken seriously by any real scientist, I strongly suggest that you continue to repeat the 3% nonsense.”
Oh, boy, that proscription sends shiver’s up my spine. Ooh, I think I’m soiled.
Joel Shore says:
)” (1) It doesn’t address the question of interest…which is not how long it takes a particular carbon atom to cycle out of the atmosphere but how long it takes a perturbation in the total atmospheric level of CO2 to decay. They are different things.
(2) It is not obvious from that graph that the lifetime is what you claim it to be. As I noted, the decay of CO2 is simply not described well by a single lifetime…So, some fraction of a perturbation in the CO2 levels disappears quite quickly but there is also a long tail. Whether the long tail is there or not for what you have plotted can’t really be determined from what you showed.”
First: You are ignoring the fact that C14 is continually formed in the upper atmosphere by cosmic ray bombardment. The graph shows the excess C14 injected by atmospheric A-bomb tests (the “perturbation”) decaying back to the natural background concentration. The “long tail” is simply the natural background concentration of C14. When you include this in the model, it is fit well by a single lifetime.
Second: The graph demonstrates that there is a real-world process which removes ½ of all radioactive CO2 from the atmosphere every 10-15 years. While it is just possible that the removal process might run at a slightly different rate for C12 than C14, the difference can not be great, so it is reasonable to consider that the lifetime for ALL atmospheric CO2 is ~12 years.
The graph also demonstrates exactly how long it takes a perturbation in CO2 levels to decay – since that is precisely what it is measuring. So, indeed, it does directly address your “question of interest”.
This also means, that half of the the CO2 released this year by Human activity will be gone from the atmosphere in 12 years; as there is no way any physical mechanism can distinguish where a “particular” CO2 molecule comes from.
I know it is fashionable over at RealClimate to yap about “long tails” and “multiple lifetimes”, but there is exactly NO evidence for any such phenomenon. The only thing that might partly save this theoretical House of Cards is the demonstration that the CO2 lifetime is a sensitive function of concentration. AGWers, however, have made NO attempts to make any such measurements – probably because measurements of CO2 lifetimes around 10-15 years (the probably outcome) would be, as I said, a highly “inconvenient fact”.
Dr. S has alerted me, on another subsequent occasion, that my use of ‘variance’ above is inappropriate; should have been ‘variability’.