Guest Post by Steven Goddard part 1 is here
Ice cores clearly demonstrate the close relationship between atmospheric CO2 levels and temperature, as seen below.
This relationship has been well understood by geologists for longer than Al Gore has been alive.
As ocean temperatures rise, the solubility of CO2 in seawater declines. Thus increasing ocean temperature moves CO2 from the ocean into the atmosphere, and decreasing ocean temperatures move CO2 out of the atmosphere and back into the ocean. As you can see in the graph below, a 10C shift in temperature causes about 30% reduction in dissolved CO2. Closely corresponding to what we see in the measured ice core graph above.
Ice ages are driven by orbital cycles of the earth, and as ocean temperatures change, atmospheric CO2 levels respond – in accordance with the laws of chemistry. The relationships are uncontroversial.
Unfortunately, some educators besides Al Gore have taken liberties with the ice core data. Children’s global warming author Laurie David published the incorrect graph below, which shows that CO2 levels changed prior to the temperature levels. The graph misleads children into believing that ice ages are driven by changing CO2 levels, rather than the other way around. It is difficult to understand how this error could have happened accidentally.
http://scienceandpublicpolicy.org/images/stories/papers/other/graph1.gif
This week is National Engineering Week in the US, when elementary school children are encouraged to learn math and science. Don’t they deserve and need accurate information? Are Laurie David’s book and Al Gore’s movie acceptable in a science classroom?
Whether or not you believe that the burning of fossil fuels significantly affects the earth’s temperature, the ice core data offers no evidence to support that – no matter how big the graph is.
Philip_B (14:44:01) :
There’s no doubt that the positioning of a landmass over the South pole and significant land mass in the Arctic are important for glaciation.
Hower the Milankovitch cycles account very well for the glacial-interglacial oscillations within the glacial period of the last million-ish years. There are actually three cycles [~100,000 year (eccentricity), 41,000 year (obliquity) and 23,000 year (precession)], and since these are out of phase, the pattern of inslation variation is quite complex.
However if one takes the parameters of delta-temperature or delta 18O from the Vostock or Dome Fuji cores and Fourier transforms these with respect to time, strong peaks at frequencies at 111 kyr, 41 kyr and 23 kyr stand out pretty clearly in the power spectrum[***]. So the changes in frequencies in the glacial cycles may relate to the dominance of eccentricity in more recent periods compared to earlier periods where the obliquity cycle dominated….I’m not sure whether that “switch” of dominance is well understood or not…
[***]e.g. see Figure 3 of: Kawamura et al (2007) “Northern hemisphere forcing of climate cycles in Antarctica over the past 360,000 years” Nature 448, 912-919
RE: CO2 levels in ice cores:
As Robert Austin points out, most of the CO2 rise pre-dates the increase of CO2 emissions from burning fossil fuels post WW2.
Which says to me that the CO2 levels in ice cores is an artifact of recent ice layers (ie, the last 200 years of ice cores give misleading data on atmospheric CO2). The other possibility is a changes is agricultural practices since the early 1800s.
Anyway, burning fossil fuels cannot possibly be the cause of most of the (apparent) CO2 rise found in the ice cores, because most of the CO2 rise pre-dates the fossil fuel burning.
Philip_B (15:24:11),
Thanks for that interesting link! In one click, you have reduced the alarmist contingent’s [bogus] scare over catastrophic sea level rise by half.
Of course, the AGW/CO2 scaremongers don’t realize this information cuts them off at the knees. To them, it’s still only a scratch: click
Philip_B (15:24:11) :
The Antarctic ice sheet is indeed mostly over the ocean. We have recently discovered through radar images that Antarctica is not the contiguous continent we thought it was and most of the Antarctic ice sheet rests on the ocean. See link below.
So the claims of x meters rise in sea level if the Antarctic were to melt (which of course it won’t) should be revised down by around 50% on the basis of this new evidence.
What is disturbing is the way AGW advocates ignore new scientific discoveries and cling to their outdated and now disproved dogma.
Philip, there’s nothing revelatory about the fact of Antarctic bedrock being below sea level – especially the WAIS. This is a cause for concern, not complacency! It does not mean that the ice sheet – – which averages about a mile thick – is displacing its weight in water. It is supported by the bed-rock, whether below sea level or not, and not supported by the ocean. Please imagine a bridge whose weight is supported by the foundations below the water level, and not by the water itself. It’s uncontroversial that if the ice sheet were to melt the land beneath would rise, being relieved of the weight.
Whichever way you think about it, we have good knowledge of sea levels when there were no ice sheets. Unless you think the water has disappeared somewhere else then such levels can broadly be anticipated if the ice sheets were to melt (which I don’t happen to think they’re about to do any time soon).
But I’m conscious of posting too much on this thread, so shall say cheerio. All the best 🙂
If you will compare the Atmospheric CO2 numbers from here:
ftp://ftp.cmdl.noaa.gov/ccg/co2/trends/co2_mm_mlo.txt
You will see a very definite correlation between temperature, and the amount of CO2 retained in (gassed into?) the Atmosphere. The biggest example is 1998 vs 1999, and 2000. The most recent example is “right now.” CO2 is increasing in the atmosphere at about a 1.60 ppm/yr rate, down from the approx 2.00 ppm/yr rate it was running at prior to 2008.
Philip_B (16:49:58) :
Not really. Most of the rise in atmospheric CO2 post-dates the post-war industrialisation, especially the period from the early-mid 60’s.
so in 1800 [CO2] was near 284 ppm (the medieval levels were in the range 275-282 ppm)
in 1900 it was near 299 ppm
in 1940 it was near 308 ppm
in 1960 it was around 319 ppm
it’s around 385 ppm now.
so in the 800-ish years to 1800 [CO2] levels rose by a few ppm nett.
1800 to 1900 gave us around 15 ppm altogether (about 20 ppm cumulative)
1900 to 1940 gave us around 9 ppm altogether (around 30 ppm cumulative)
1940 til now gave us around 77 ppm (107 ppm cumulative)
Data are from:
D. M. Etheridge et al (1996) “Natural and anthropogenic changes in atmospheric CO2 over the last 1000 years from air in Antarctic ice and firn J. Geophys Res. 101, 4115 -4128.
and direct measurement from the Mauna Loa station from 1959
Column 1 is the year, column 2 is the [CO2] in parts per million, and column 3 is the yearly increment in the period from 1959. Ice core data from Etheridge (up to 1959) from a series of Antarctic (Law Dome) cores.
1006.0000 279.4000
1046.0000 280.3000
1096.0000 282.4000
1146.0000 283.8000
1196.0000 283.9000
1246.0000 281.7000
1327.0000 283.4000
1446.0000 281.7000
1499.0000 282.4000
1547.0000 282.8000
1589.0000 278.7000
1604.0000 274.3000
1647.0000 277.2000
1679.0000 275.9000
1720.0000 277.5000
1760.0000 276.7000
1796.0000 283.7000
1825.0000 285.1000
1845.0000 286.1000
1861.0000 286.6000
1877.0000 288.8000
1882.0000 291.7000
1891.0000 294.7000
1899.0000 296.5000
1905.0000 299.0000
1912.0000 300.7000
1926.0000 305.0000
1936.0000 307.9000
1948.0000 311.4000
1954.0000 314.7000
1959.0000 315.7000
1959.0000 318.2000 0.9400
1960.0000 319.2000 0.5000
1961.0000 319.7000 0.9600
1962.0000 320.7000 0.6500
1963.0000 321.3000 0.7400
1964.0000 322.0000 0.3000
1965.0000 322.4000 1.0700
1966.0000 323.4000 1.2600
1967.0000 324.7000 0.6800
1968.0000 325.4000 1.0400
1969.0000 326.4000 1.3700
1970.0000 327.8000 1.0000
1971.0000 328.8000 0.7800
1972.0000 329.6000 1.7900
1973.0000 331.4000 1.1800
1974.0000 332.5000 0.7600
1975.0000 333.0000 1.0900
1976.0000 334.0000 0.9000
1977.0000 335.3000 2.0700
1978.0000 337.4000 1.3400
1979.0000 338.7000 1.6400
1980.0000 340.0000 1.8400
1981.0000 342.0000 1.4400
1982.0000 343.6000 0.7100
1983.0000 344.0000 2.1600
1984.0000 346.4000 1.3500
1985.0000 347.8000 1.2200
1986.0000 349.0000 1.5100
1987.0000 350.0000 2.3500
1988.0000 352.8000 2.1100
1989.0000 355.0000 1.2800
1990.0000 356.2000 1.3100
1991.0000 357.6000 0.9900
1992.0000 358.5000 0.4500
1993.0000 359.0000 1.3100
1994.0000 360.3000 1.8900
1995.0000 362.2000 2.0100
1996.0000 364.2000 1.1900
1997.0000 365.4000 1.9800
1998.0000 367.4000 2.9500
1999.0000 370.0000 0.9100
2000.0000 371.2000 1.7800
2001.0000 373.0000 1.6000
2002.0000 374.6000 2.5500
2003.0000 377.1600 2.3100
2004.0000 379.5000 1.5400
2005.0000 382.0000 2.53
2006.0000 384.0000 2.00
Steven Goddard there is an enormous literature on paleoclimate change which contradicts your simplistic assessment. Warming does not happen everywhere at the same time, and CO2 and temperature form a feedback not a simple cause and effect.
This literature is also clear that the orbital and ice albedo feedbacks are far to small to explain the warming/cooling. Take a lookie at the lead lag correlations and you find they are positive with both CO2 leading and with temperature leading.
Dear Anthony, Steven and Ferdinand,
thanks for this blog as it gives me the opportunity to ask and old question ..
First of all the solubility graph is not complete, as it assumes, that the partial pressure in the amtosphere does not change.
My question is:
Can we really exclude the oceans as major sources for the CO2?
Ferdinand writes:
“That includes the measured increase of CO2 in the oceans, the decrease in pH of the oceans, the decrease of d13C in atmosphere and oceans (which excludes the oceans as main source), the deficiency in oxygen use, which excludes the biosphere as main source and last but not least the mass balance: We emit twice as much CO2 as what is found in the atmosphere. The rest is absorbed by nature as a whole, which by definition of non-destruction of mass excludes nature as source of the increase…”
My statement to that points would be (please correct me if I am wrong):
– we could NOT measure an increase of the total CO2 in the oceans!
(Also the pH-value of the ocean did not change due to human CO2! There is indication that it has changed for the near surface sea water, but that is a much smaller volume than the total seas!)
Only a certain depletation of the C13-Isotope was shown, which only indicates, that the anthropogenic CO2 goes (not surprisingly) into the sea’
Please give me a reference of the total ocean CO2-concentration before and after a human impact with error bars! How can you build a mass balance while the total amount of oceanic CO2 is rather unkown?
– the C13-depletion is a result of the burning of fossil fuel, that does not indicate by any means, that the rise in CO2 is manmade.
Would (as I wonder) the oceans be a main contributer for the atmosphere, the depletion would look the same.
My question to you would be: Where were most of the athmospheric CO2-molecules 20 years ago? (With a exchange time constant of 5 years math tells you, that most (95%+) of these molecules come from the sea!)
And:
How would a otherwise unchagend ocean react to an sudden increase of athnospheric CO2 by 30%? It would absorb CO2 like crazy (actually the absorption should only be 3% higher than the desorption due to the Revelle factor), but we don’t seem see that . . could this fact alone mean, that the idea of a pure anthropogenic reason for the atmospheric CO2-rise is wrong?
(As Steven writes is takes about 10K to increase the partial preassure of the sea suffitiently, we did not get there yet and still the sinks and sources for marine CO2 are almost balanced . . why?)
If you rightly assume, that the near surfrace sea water has already risen to a higher CO2-level and is close to an equilibrium with the atmosphere, this only pushes the same question one level deeper:
Why isn’t the anthropogenic CO2 simply dumped into the deep see?
In 1957 Craig gave a time constant for this mechanism of 8 years, which should mean, that any rise of CO2 in the atmoshphere+upper sea water is simply washed out in a few decades ..
Or in other words:
The fact, that we see a slow rise in CO2, means that a process with a long time constant is at work and this should involve the deep ocean.
(CO2 rise as a result of a medival warm period!?)
So far no one tries to claim, that the human CO2 amount has any significant influence on this reservoir, but probably I misunderstood Ferdinand here.
All the best,
LoN
whoops! The tabs seem to have been lost from the CO2 column data posted just above.
for clarification the data:
“1006.0000 279.4000”
means that in 1006 AD, atmospheric CO2 in the Law Dome cores was 279.4 ppm
and:
“1959.0000 318.2000 0.9400”
means that in 1959 atmospheric CO2 was 318.2 ppm and the annual increment was 0.94 ppm.
>Anyway, burning fossil fuels cannot possibly be the cause of most of the (apparent) CO2 rise found in the ice cores, because most of the CO2 rise pre-dates the fossil fuel burning.
No it does not. ADD you can’t see the anthropogenic CO2 rise in Vostok and similar cores anyway because it takes hundreds of years for bubbles to form because the place is a desert.
Steven has also pulled a swifty – notice no in situ data is used for the temperatures in that graph…. The end of the temprerature graph should be vertical on that scale.
This is an attempt to reconcile the following facts:
1. The average residence time of a CO2 molecule in the atmosphere is five years.
2. The atmospheric CO2 level is therefore in effective equilibrium with the oceans, or part thereof.
3. Atmospheric CO2 has gone up by 30% from the preindustrial level.
4. The oceans as a whole have not gone up by 30% in terms of CO2 content.
Following is the logic at arriving at the conclusion that the atmosphere is effectively in equilibrium with the top 100 metres of the ocean, on average:
1. The oceans have a thermocline at an average depth of 400 metres, with an average temperature of 5 degrees below the thermocline down to an average depth of 3,800 metres and an average temperature of 14 degrees above the thermocline
2. Of the 38,000 gt of carbon in the oceans, 9.7% is above the thermocline due to the lower solubility at the higher temperature. This amounts to 3,685 gt.
3. The preindustrial atmosphere had 580 gt in it
4. The ratio of above thermocline carbon to preindustrial atmospheric carbon is 6.35 to 1.
5. Mankind has put 360 gt of carbon into the atmosphere, of which 60 gt went into biomass, 120 gt went into the oceans and 180 gt stayed in the atmosphere.
6. At the same time, the oceans above 400 metres warmed by 0.7 degrees, resulting in the oceans wanting to emit 128 gt to the atmosphere due to the lower solubility. Effectively this carbon remained in the oceans due to maintenance of the partial pressure equilibrium with the atmosphere.
7. But the atmospheric level rose 30%, which means that the part of the oceans that the atmosphere is in equilibrium with also had to rise 30%.
1. To get an equivalent rise in the oceans of 30%, the atmosphere is effectively in equilibrium with the top 100 metres on average.
Of course the real world is a lot more complex with carbonate buffering and changing depths to the thermocline with latitude. A lot can be read from this graphic:
http://cdiac.ornl.gov/oceans/glodap/atlas/p16dic.jpg
Note that the surface waters have a lower CO2 content than the bulk of the ocean, even though they have been in equilibrium with elevated atmospheric CO2 levels for the last 100 years. Bottom water is formed from cooling of surface water in the southern ocean. So how can bottom water have a higher CO2 content when it is being made from surface water with a lower CO2 content? The only answer is that the surface waters are being depleted of CO2 by the formation of organic matter which then descends into the bottom waters where it is oxidised to CO2. Raising the atmospheric CO2 level will speed up the biological pump in the surface waters that is raining organic matter into the ocean depths.
What most people don’t realise is that the ocean bottoms are relentlessly oxidising. That is why deep ocean muds are red. If it was anaerobic, they would be black. I remember from my Exxon training that the oxygen minimum is at 400 metres, part way down the continental slope. It doesn’t mean that it is not oxidising at 400 metres. You have to have a reasonably rapid sedimentation rate to preserve organic carbon. It also means that the attempts to demonstrate oceanic sequestration of carbon dioxide by surface water fertilisation just amount to playing around in boats.
If the world cools 2 degrees to 2030, as predicted by my solar analysis, then the top 100 metres will want to absorb carbon dioxide from the atmosphere equivalent to the anthropogenic contribution over the same period. It will be like the CO2 dip associated with Pinatubo but for a lot longer.
P.S. On that CDIAC site, you will find experiments in which they poisoned plant growth experiments with ozone so the results wouldn’t be positive. The things you have to do to keep your funding (no positive results from increased atmospheric CO2 are allowed).
This study if valid raises some serious quesitons about the validity of extraction and analysis of trapped gas bubbles in ice cores.
http://www.co2web.info/np-m-119.pdf
It indicates the bubbles are sealed off as the snow level gets buried and then as the ice layer gets pressurized deep in the ice pack the bubbles entirely disappear. They only reform when the deep ice is “decompressed” as it is cored. The report indicates that there is considerable doubt about the assumption that the bubbles are truly sequestered from the environment and raises the question that there may be paths for gas exchange even in very cold ice due to absorption in very thin layers of liquid brine between the ice crystals.
Makes you wonder if the old CO2 levels really are representative of the ancient atmosphere at all?
Larry
CO2 increased in the atmosphere 0.22 from Jun 92 to Jun 93. 1.19 from Jun 93 to Jun 94, then Exploded up 2.43 Jun 94 to Jun 95.
That’s an awful lot of CO2 appearing, and disappearing awfully quickly.
Kum Dollison (18:17:04)
Isn’t that similar to what scientists reported over the past couple of centuries? Beck et al. compiled information showing a big rise in CO2 in the 1940’s, and an even bigger rise in the early 1800’s.
The claims that CO2 has remained flat at around 280 ppmv until recently should be viewed with well deserved skepticism.
Smokey, I haven’t read anything here, or anywhere else, that I would be comfortable “investing” in (CO2-Wise.)
“Steven Goddard (09:19:56) :
I might add that anyone who has ever opened a warm beer is aware of the fact that CO2 solubility decreases with temperature.”
I’d rather open a cold one, Bass Ale preferably (1777 was a good year), listen to some good music, have a nice time with friends, and forget about this global warming CRAP
Thanks David
This answers all my questions (above) regarding CO2 !
Makes me wonder about the CO2 that forms over the South Pole of Mars during it’s winter, then evaporates to reveal the Water Ice underneath.
Why doesn’t the CO2 ice sink?
And why isn’t there a bunch of C02 ice in with the water ice?
Fizz.
We should have gone on with the plans to visit Mars in the 80’s.
None of this AGW crap would be stinking up the planet.
All of science would have know better decades ago.
Philip_B and Foinavon:
In my earlier post was only addressing the graph linked by Ferdinand Engelbeen. Other constructions may show the historic CO2 record differently. Ferdinand Engelbeen’s graph shows a definite hockey stick shape with an abrupt and steep rise starting about 1800, albeit with an even steeper rise closer to modern times.
It makes sense that man’s carbon dioxide emissions have increased the atmospheric CO2 concentration above what it would be without the consumption of fossil fuels. The additional CO2, even though it is only 3% to 5% of the natural flux, is a perturbation and will have some effect on the system. As I understand it, by measuring the C12 / C13 ratio, it is hypothesised that 50 % of the man’s carbon emissions contribute to the increase from the supposed ideal of 290 ppm. The remaining 50% of anthropomorphic CO2 emissions disappears into the vast system of carbon flux, probably dissolved in the oceans. But this 50% hypothesis depends on how solid is the science of the C12 / C13 proxy. And the whole historical CO2 reconstruction seems to largely depend on whether ice cores retain pristine samples of ancient atmosphere. Yet we skeptics would be content to let the palaeoclimatologists labour away refining their science in relative security had they and other climate scientists not played their hands so prematurely. The demands for extraordinary sacrifices by the world’s citizens demands extraordinary due diligence. And the whole discussion is only a prelude to the issue of whether the possible doubling of CO2 from the “ideal” 290 ppm will alter climate appreciably.
Just want the truth, wrong thread. The crap is near the treatment plant in the above thread.
I must admit that this use of a James Hansen study gives me pleasure (sort of using his own work against him).
http://pubs.giss.nasa.gov/docs/1974/1974_Lacis_Hansen_1.pdf
But according to this (page 119 or page 2 of the pdf) CO2 only absorbes a specific wavelength of solar energy (also the weakest in the graph). That same wavelength of energy is also absorbed by H2O which is 10X more of a greenhouse gas in its effect. Now it is clear that energy that is absorbed by H2O cannot also be absorbed by CO2. It is also clear that the energy absorbed by CO2 is logarithmic/non-linear with increases in concentration (Beer’s Law) so that at current levels (385 ppm) any increase in CO2 will have a negligable greenhouse effect.
http://brneurosci.org/co2.html
While pondering just how cold the S. Pole can get during an ice age cycle (when insolation can be 5%+ less than now due to orbital mechanics and polar tilt…) I once again pondered CO2 Clathrate ice formation… i.e. CO2/water ‘snow’ and did another bit ‘o googling… This turned up an interesting summary …
Unexpectedly stable clathrate hydrates formed from microporous vapor-deposited amorphous solid water at low “external” guest pressures and their astrophysical implications
Andreas Hallbrucker and Erwin Mayer
Institut für Anorganische und Analytische Chemie, Universität Innsbruck, A-6020, Innsbruck, Austria
Received 6 August 1990; revised 28 November 1990. Available online 25 October 2002.
Abstract
Oxygen clathrate hydrate which was used as a model substance for other clathrate hydrates with highly volatile guest species was formed from microporous vapor-deposited amorphous solid water prepared at 77 K, and from O2 enclosed in the pores during heating and sintering of the amorphous deposit up to ≈120 K, with “external” O2 pressures during the sintering and gas enclosure process of 10, 100, 200, and ≈ 1700 mbar. Clathrate hydrate formation occurred between ≈170 and 210 K as seen by X-ray diffraction. If was stabilized by layers of ice and decomposed completely on heating at a rate of 10 K min− only between 240 and 250 K, which is much higher than anticipated from dissociation pressure/temperature curves. Astrophysical implications with respect to (i) the temperature of formation of clathrate hydrates, (ii) their stabilization by layers of ice, and (iii) the low-temperature decomposition of CO2-clathrate hydrate are discussed briefly.
So, an ‘oxygen clathrate’ that stays stable up to 240K (!) and much higher than anticipated…
The implication being that very very cold ice (snow) formation might very well make CO2 clathrates (and thus either 1) Scrub the air really really well or 2) screw up the ice core records…
So much for ‘settled science’…
Steven Goddard (15:30:33 20 February) :
I have a standing discussion with a few scpetics for over 2 year now, that the current CO2 rise is NOT from human origin (even Dr. Spencer thinks that maybe the oceans are involved). But that is an aside here in this discussion.
Ocean pH levels were measured historically, but with higher accuracy in the past decades. At two places (Hawai in the Pacific and Bermuda in the North Atlantic) continuously (since 1990) and with several seaships on a regular basis. In the past few years an armada of buoiys add to our knowledge.
The Hawai and Bermuda time series (1990-2000) show a drop in pH of about 0.02 units, where Bermuda has a higher seasonal amplitude, which makes the trend more difficult to see (Fig. 1-2):
http://www.isse.ucar.edu/florida/report/Ocean_acidification_res_guide_compressed.pdf
The accuracy of the pH measurements can be as good as +/- 0.0001 pH unit, for practical purposes anyway better than +/- 0.001 pH unit, sharp enough to see a drop over a decade.
These are the only time series on line, but more coverage to come in a few years from now.
http://en.wikipedia.org/wiki/File:AntarcticBedrock.jpg
I find it interesting that the ‘hot’ part of Antarctica is mostly over water while the ‘cold’ part is over land… Maybe the issue has more to do with warmer oceans and/or volcanically heated water than it does with CO2…
Ozzie John (15:44:31) :
Is it possible that the decreased pH of the oceans has another driver ?
Our current observations would make this a likely scenario !
Indeed it is possible that a lower pH drives out a lot of CO2, far more than temperature can do. That is used in the latest (personal) discussions I have about the origin of the current increase. But that doesn’t fit with the observation of the decrease in d13C of atmosphere ánd oceans: the deep oceans have a d13C level of about zero per mil d13C, the upper layer (due to algue growth) of 1-4 per mil (and decresaing, for an introduction of d13C levels in different media, see: http://homepage.mac.com/uriarte/carbon13.html ), the atmosphere is at – 8 per mil (and decreasing) and fossil fuel burning is at -24 per mil in average.
Even if there is some isotope fractionation at the water-air border (in the two directions), the release of CO2 from the oceans should slightly increase the d13C level of the atmosphere, while we see a strong decrease. Not fully as what can be calculated, as there is a dilution of the human “fingerprint” of d13C, as about 20% of the atmospheric CO2 each year is exchanged with ocean and biosphere CO2 over the seasons. But the addition in mass still is only from the emissions…