Study: Southern ocean was a big CO2 sink during last ice age

In the Southern Ocean, a carbon-dioxide mystery comes clear: Sediments show greenhouse gas taken from air

From the THE EARTH INSTITUTE AT COLUMBIA UNIVERSITY

Researchers have found that bottom waters of the Southern Ocean had very low levels of oxygen during the last ice age, indicating high uptake of carbon. Here, dissolved Southern Ocean bottom-water oxygen in modern times. Brighter colors indicate more oxygen; dots show sites where researchers sampled sediments to measure past oxygen levels. CREDIT Jaccard et al., Nature 2016

Researchers have found that bottom waters of the Southern Ocean had very low levels of oxygen during the last ice age, indicating high uptake of carbon. Here, dissolved Southern Ocean bottom-water oxygen in modern times. Brighter colors indicate more oxygen; dots show sites where researchers sampled sediments to measure past oxygen levels.CREDIT Jaccard et al., Nature 2016

Twenty thousand years ago, when humans were still nomadic hunters and gatherers, low concentrations of carbon dioxide in the atmosphere allowed the earth to fall into the grip of an ice age. But despite decades of research, the reasons why levels of the greenhouse gas were so low then have been difficult to piece together.

New research, published February 3rd in the leading journal Nature, shows that a big part of the answer lies at the bottom of the world. Sediment samples from the seafloor, more than 3 kilometers beneath the ocean surface near Antarctica, support a long-standing hypothesis that more carbon dioxide was dissolved in the deep Southern Ocean at times when levels in the atmosphere were low.

Among other things, the study shows that during the ice age, the deep Southern Ocean carried much smaller amounts of oxygen than today. This indicates that photosynthetic algae, or phytoplankton, were taking up large amounts of carbon dioxide near the surface. As dead algae sank to the depths, they were consumed by other microbes, which used up the oxygen there in the process. The scientists found chemical fingerprints of the oxygen level by measuring trace metals in the sediments.

The evidence “is a long-sought smoking gun that there was increased deep ocean carbon storage when the atmospheric CO2 was lower,” said Sam Jaccard of the University of Bern, Switzerland, the study’s lead author.

Coauthor Robert Anderson, a geochemist at Columbia University’s Lamont-Doherty Earth Observatory, said the study “finally provides the long-sought direct evidence that extra carbon was trapped in the deep sea by the buildup of decaying organic matter from above.” He added, “It’s also clear that the buildup and release of CO2 stored in the deep ocean during the ice age was driven by what was happening in the ocean around Antarctica.”

The study also shows that variations in carbon-dioxide storage in the Southern Ocean were probably behind a series of natural “wobbles” in atmospheric levels of about 20 parts per million that took place over thousands of years. The study suggests that the wobbles were probably caused by changes in the amount of iron-rich dust, which fertilizes phytoplankton, being blown from land onto the ocean surface. Levels may also have been influenced by varying amounts of carbon being released from the deep ocean as ocean currents changed, said the authors.

The study may hold powerful lessons for today. While the natural 20-part-per million wobbles took thousands of years to happen, carbon dioxide levels have risen that much in just the last nine years, due to human emissions. Levels are now about 400 parts per million, versus about 280 in the early 1800s. “The current rate of emissions is just so fast compared to the natural variations that it’s hard to compare,” said study coauthor Eric Galbraith of the Autonomous University of Barcelona. “We are entering climate territory for which we don’t have a good geological analog.”

###

The study was also coauthored by Alfredo Martinez-Garcia of Germany’s Max Planck Institute for Chemistry.

68 thoughts on “Study: Southern ocean was a big CO2 sink during last ice age

    • Several entries at climate4you.com(Ole Humlum) give good examples of why using regression techniques- drawing lines through a collection of data points- does not give a true picture of what is represented. Look under climate reflections, 20080911.

      It’s particularly important when data has a trend. Standard deviation and confidence intervals don’t apply. They only apply to Gaussian data(that with a particular symmetric standard deviation). Various statistical techniques have been developed, collectively called Auto Regressive Integrated Moving Average(ARIMA), which remove the errors highlighted in the article.

      • If there is a gaussian , random, error in global temperature it is in the rate of change of temperature , which itself is strongly auto-regressive.

        ARIMA includes “MA” : moving average aks running mean which is a crap form of low pass filter that distorts data and inverts peaks to troughs etc.

        https://climategrog.wordpress.com/2013/05/19/triple-running-mean-filters/

        Any such analysis should be done on dT/dt and use well-behaved filters , not crap running means.

      • Temperature is auto-regressive, so any “trend” in temp is random walk. I you want to use any statistics that assume random “normal” or “gaussian” distributions: work in dT/dt.

      • I looked at the dT/dt of the GMTA a while back when I first became interested in AGW so I did a simple analysis using a running mean. I also did a quick check of how good it was by doing a cumulative plot of the rates (and offsetting).
        http://postimg.org/image/6o26kgkf7/?_ga=1.184993070.668630845.1454622041
        I didn’t do an R2 calculation but its pretty obvious that with a ±0.1°C for monthly anomalies that the simple analysis is good enough.

        What I never understood was why you couldn’t do this but you could use an auto-correlation analysis to calculate a large error for a linear regression and then claim that the pause was debunked.

      • A collection of data points gives a true picture of what is happening. In fact it’s the only thing you know about what is happening. All the rest is conjecture.

        G

        ARIMA is aptly named particularly that Regressive part. Pure numerical Origami !

  1. Twenty thousand years ago, when humans were still nomadic hunters and gatherers, low concentrations of carbon dioxide in the atmosphere allowed the earth to fall into the grip of an ice age. 20 K years ago we began to emerge from 80 K years of glaciation, another cycle in 400 K years of the current ice age. After reading that sentence there was no need to read more of this nonsense.

    • When oh when will these morons admit that cold water sinks CO2 and warm water sources CO2. CO2 from the oceans is a lagging indicator of temperature, not a leading one. I guess, none of them have even had the experience of opening a bottle of warm seltzer.

      • Those morons need first to brush up on their climate history before they can even start to apply their alleged science. As skeohane pointed out, it was 20,000 years ago when the world started to come out of a major glaciation period. How in the world these papers can get past peer review is beyond me. Do not any of these climate scientists know anything about climate history?

      • So atmospheric CO2 has gone up by a factor of 1.4 from 280 ppm to 400 ppm, since long before the industrial age, with possibly a 0.6 deg. C increase in Temperature, but when it went down to 260 ppm way back when, it plunged the earth into an ice age.

        Well back then, pigs were flying too.

        CO2 IR absorption heats the atmosphere. (they claim) So less CO2 cools the atmosphere.

        A cooler atmosphere holds less water (H2O). That means precipitation will remove more clouds, which leaves less clouds.

        Less clouds block less sunlight, so you get an increased solar warming of the surface of the earth.

        A warmer earth surface warms the atmosphere by conduction, convection, evaporation and radiation.

        Those are perfect conditions for triggering an ice age, specially if the CO2 goes down by a whopping 20 ppmm.

        The north pole CO2 in the atmosphere goes up and down 18-20 ppmm every year.

        Oh I guess that does trigger a local ice age, as ice comes and goes in the arctic ocean every year just as predictable by this new theory.

        Wunnerful; simply wunnerful !

        g

      • When oh when will these morons admit that cold water sinks CO2 and warm water sources CO2.

        I think the “morons” just published a peer reviewed paper in a usually alarmist journal, not just suggesting, but proving that was the case.

        When will the ‘morons’ that inhabit WUWT stop the knee-jerk wailing and sarcasm and actually read and realise when supportive evidence gets published.

      • To Mike. I will happily read their papers when they cease to become an escathological cargo cult and they become science. The ones I have read have represented lost time in my life that I will never get back in exchange for reading absolute rot.

      • The morons will never admit to that, ShrNfr – nobody is as blind as the one who refuses to see. They simply cannot wrap their brains round the fact that the CO2 increase happened long after the temperature increase. They MUST be willfully blind, I think.

    • skeohane – a graph might help:

      The idea that Earth fell into the grip of an ice age 20,000 years ago is so ridiculous it isn’t funny.

      • Mike Jonas,

        That graph is a little small. Click in this one to view a larger pic:

        Here’s another one:

        [Note: Holocene on left. Click in chart to embiggen]

      • Well the day that Vostok Temperature is at either -4 deg. C or 4 kelvin, I’m going to retire.

        Now -94 deg C I would believe, some of the time, but not -4.

        G

      • K is an absolute Temperature scale.

        1K is colder than the freezing point of hydrogen. Delta T is in deg. C (Celsius).

        Don’t have any degrees K, just plain K.

        G

      • In the 1980’s for a year or two I worked with an electronic communication engineer (late Robert Kelvin Flood-Thain ) descendant of the Lord Kelvin.

    • Yep, pretty dumb to suggest that cold water absorbs CO2, right? What a bunch of morons. Next they will be suggesting that warming waters release CO2. How dumb can you get ?!

      • Are you really that stupid, Mike? What part of “low concentrations of carbon dioxide in the atmosphere allowed the earth to fall into the grip of an ice age” did you not comprehend? The fact that cold water absorbs more CO2, and warm water releases it is grade-school stuff. Is that what you really think this paper is about?
        Go back to Trolls R us.

      • I have no problem with the water sinking or sourcing CO2 in response to temperature. Cold water, such as you might get during an ice age, will sink CO2, warm water, such as you might get in any of the warming periods will source CO2. The hypothesis that the sinking of CO2 caused an ice age is absurd on its face. In order to be a net sink it had to be cooling already. Since we know that the CO2 concentration was above the 175 ppm that is necessary for green plants to survive, you have CO2 in the range of perhaps 175ppm to (say) 250 ppm. That would hardly create an ice age, but an ice age would create sinking of CO2 in the ocean. Got it now, or did you flunk high school chem and not understand soda pop.

      • Mike February 4, 2016 at 11:06 am
        Bruce Cobb February 4, 2016 at 12:15 pm
        dbstealey February 4, 2016 at 1:01 pm

        I think part of the problem with this article is it reads like a press release, not a abstract. Things like where their start date for min and max on co2 is. also from what years of the ice age are they referring? The list is long.

        michael

  2. Wasn’t CO2 at 280 PPM for 2 million years until recently ? The temperature varied greatly in that time, so their conclusion is wrong.. CO2 does not control temperature…

  3. Quite agree with skeohane, I quit reading there and laughed. I was reminded of the Jamaican belief that opening the refrigerator without shoes on will cause pneumonia.

  4. If “the current rate of emissions is just so fast compared to the natural variations that it’s hard to compare”, maybe just maybe, the emissions are NOT affecting the variations.
    Over the course of the satellite record CO2 levels in the atmosphere have risen nearly 20% – the global temperature, well, not so much.

      • funny thing is, the lower troposphere is warming slower than the surface, while climate science predicted the opposite. which in any other branch of science would constitute falsification. a failed theory.

      • Let’s what everybody doesn’t understand, the temperature increase from 180 to 360 ppm CO2, is the same temperature change as it would now take to go 400 to 800 ppm. Since the ECS, Equilibrium Climate Sensitivity is likely to be less than 2.0, it not enough to get us into their beloved apocalyptic temperature zone with out added warming from water vapor; yet water vapor is much more likely to transport heat above the CO2 layer than it is to retain it.

  5. Why are you allowed such alarmist rubbish to be printed Anthony? Saying low CO2 “caused” low temperatures is stupid and unsupported by the science which shows the greenhouse effect of CO2 is far far too small to cause the 8C change needed.

    But by allowing this kind of conspiracy ideology onto your site you are in effect endorsing the view that a small change of CO2 can cause a massive change in temperature (if I remember right its a feedback of the order of 10x that is required – far higher even than the moronic stuff now produced by even the worst climate alarmist.

    And there is very clear evidence CO2 does not cause the change, as several times after the interglacial, the world has been plunged into a very cold period (~6C cooler) with very little change in CO2.

    And I know all this because I tried to find a way to include CO2 as part of a feedback mechanism – and unfortunately (as I nearly had a mechanism) it just cannot work.

    • “It’s also clear that the buildup and release of CO2 stored in the deep ocean during the ice age was driven by what was happening in the ocean around Antarctica.”

      I find one instance of the word “caused” in the article.

      The study suggests that the wobbles were probably caused by changes in the amount of iron-rich dust…

      I suggest that you follow Willis’ usual plea and QUOTE was you are referring to instead of inserting your own paraphrased misinterpretation of what you read.

    • Saying low CO2 “caused” low temperatures is stupid

      Indeed, so who is saying that apart from you? I can’t find it.

      • I think I found it:

        Quote from the article: “Twenty thousand years ago, when humans were still nomadic hunters and gatherers, low concentrations of carbon dioxide in the atmosphere allowed the earth to fall into the grip of an ice age.”

        It looks to me like the authors are implying/assuming low concentrations of carbon dioxide “caused” the earth to fall into the grip of an ice age. i think “cause” and “allowed” are interchangeable here.

        TA

      • The first sentence ends with “low concentrations of carbon dioxide in the atmosphere allowed the earth to fall into the grip of an ice age”. You don’t see the implied causation?

        Scottish Sceptic may have taken a small amount of licence in putting the word “caused” in quotes but it is certainly what they are saying with that opening statement

        You have to wonder if that opening sentence was added purely for funding purposes since it runs counter to the probable cause of the increase in carbon storage.The whole thing seems to be recycled from the earlier publication (March 2014) by the same authors
        http://science.sciencemag.org/content/343/6177/1347

  6. Read the abstract and extended data info. Paper ismpaywalled and not worth the price.
    The Columbia press release is highly misleading, as are the authors statements in it compared to what they actually found: on millennial scales, ocean circulation and iron fertilization affect CO2 sequestration. The first is not new news; the ~800 years CO2 lag to temperature (oceans, Henry’s law) corresponds roughly with the period of thermohaline circulation, which will be changed some by glacial sea level drop as the Bering Strait and the Malacca Strait go dry. The second is not jew news either; iron fertilization is the basis for ocean geoengineering, and changes with sea level change, exposed land change, and winds.. Showing change with deglaciation is utterly unsurprising. There is no linkage to AGW, other than another demonstration that more CO2 increases the ocean biological carbon sink rate. But we knew that already also, and didn’t need PR misrepresenting paleosediment studies from around Antarctica to prove it.

    • I would gladly read the abstract if our host would be so kind as to link the paper under consideration. Since you have presumably found it , how about a link or DOI ?

  7. From the disinformation laboratory at Columbia University – we only thought it was impossible. It was only when the models showed it can’t be impossible that an unlikely rationale came to us. We had been over-thinking it. Such is the nature of settled science that anything is now possible including some fiddling with an inconvenient glaciation time line that would have been impossible in a skeptical world. It was a dark day for the scientific method when Dr. Feynman left this mortal coil.

  8. Despite the genuflections to the CO2 God to please the gatekeepers, it appears to at least have, indeed, found a strong CO2 sink. Just remember, where it can be a sink, it can also be a source.

  9. “Twenty thousand years ago… carbon dioxide in the atmosphere allowed the earth to fall into the grip of an ice age.”

    They are confusing the term “ice age” with “glacial period”. We are currently in an ice age that began more than 2.5 million year ago. We are in an interglacial of the Quaternary glaciation, Pleistocene glaciation or the current ice age.

    Even if they are talking about the last glacial period, that began about 110,000 years ago. Maybe they mean the Last Glacial Maximum which was about 26,500 years ago (or by other estimates, approximately 22,000 years ago).

    Using the term “last ice age” for the “last glacial period” has worked its way into popular usage, but it entirely confuses the subject.

    Even if they are talking about the last glacial period, that began about 110,000 years ago. Maybe they mean the Last Glacial Maximum which was about 26,500 years ago (or by other estimates, approximately 22,000 years ago).

    Using the term “last ice age” for the “last glacial period” has worked its way into popular usage, but it entirely confuses the subject.

    Is it ignorance or deliberate?

  10. While the natural 20-part-per million wobbles took thousands of years to happen, carbon dioxide levels have risen that much in just the last nine years, due to human emissions.

    How many times to we have to see the same fundamental scientific errors being made?

    What is the time resolution of these proxies? I doubt they have 50 or even 100y resolution. It is nonsense to say that there was not 20 ppmv variation in 9y if the data does not have the resolution to show that, if it was the case. This is Marcott et al all over again.

  11. I see the familiar “Whack a Moley” guidance for research in cliSci again. How do we deal with skeptics’ raising what happened to all the paleo CO2 that didn’t acidify the ocean enough to wipe out life in the seas, particularly shellfish.

    How about sequestering it in the deep ocean as dead seaweed. Yeah, but then the contrarians will say so what happened to the O2 the seaweed must have generated on a huge scale? Well bacteria ate it. But then what happened to the CO2 the bugs made… Sh!t Bill, get a grip. They won’t think of that. Besides we can always get a grant to cook up a way to handle that

  12. Another example of ‘cargo cult science’.
    If Columbia U. allows these excursions of fantasy to reach the market, they might as well be Columbia Records in the entertainment sector.

  13. george e. smith February 4, 2016 at 8:54 am
    “Well back then, pigs were flying too…..
    g “

    Hi big G, here is an alternative to the flying pigs (sorry, just release it is not politically correct to talk about pigs)
    Nevertheless, there was no Ice Age in southern Hemisphere, not many volcanoes down there.
    It is atmospheric volcanoes that keep us warm. It goes like this: the N. Hemisphere should be now in the permanent ice age. Ice slowly builds up, pushing crust down until pressure gets high enough to force magma up and volcanoes in Iceland, Kamchatka and Aleutian go pop.
    They keep popping for about 10Ky until magma is de-pressurized, and than a long slog of the ice build up restarts. So how volcanoes keep us warm? not sure, something to do with polar jet stream, so equatorial volcanoes dont count.. Iceland on average goes off once every 3-4 years. From 1600 to 1700 Iceland had less than 2 eruptions/decade, but from 1900-2000 it had 5.8 eruptions/decade. Kamchatka data is not as good but it shows similar disparity.
    (should not be taken to seriously, until I complete a paper on the subject, and than it should be completely ignored)

    • Vuk
      Excellent.

      The pig-flights of yore [per big G] contributed much more mixing to the atmosphere – as pigs are comparatively less aero-dynamic than, say, robins or vultures – so magnified mixing promoted spread of – well, whatever the watermelons think might help their religion.

      Auto
      – prepared for a vicious campaign of being ignored, also.
      Mods – apologies – I am in Serious /sarc mode tonight. This effusion is no different.

    • Howcum those porcines are non U.

      Down there in the Shaky Isles, where we really know about Volcanoes, we call those wild truffle hunters “Captain Cookers”. It was the English who brung them. The earlier Dutch (that Abel Tasman chap), just brought themselves to dinner with the Maori, and were invited to join in the festivities; which made them the center of attraction; and the main entrée.

      So when the survivors left, there was only the dogs that the Maori brought with them, and they don’t hunt truffles. I’ve washed my share of hams since then, and I’m pretty damned good at knitting link sausages.

      I think there actually are some swine at the White House, but I don’t think they actually eat them.

      G

    • Vuk, somebody already mentioned it here. Volcanoes are really getting us from ice grip, exactly way as you are saying. But it is done via dust and ash collection. It is taking some ten thousands years to build up dust layer on glaciers. Then dust layers stays on top, increasing albedo forcing ice to melt.
      Whole cycle is:
      Warm oceans, high precipitation, accumulating snow and ice, not enough dust in air, high albedo of snow/ice cover. Full ice age develops.
      Temperature plummets, snow/ice still accumulating, cold wave spreading down earth crust, tightening it, closing gaps, slowing volcanic activity.
      Pressure in Earth Mantle increases, sudden increase in volcanic activity, as you said, Earth pops. It is happening somewhere in the middle of cold cycle.
      Amount of dust increases in Earth atmosphere, accumulation of dust on snow and ice. After reaching some threshold, lower albedo causes prevailed melting over accumulation.
      Snow and ice is gone, Earth is in warm phase, oceans warming again, precipitation is increasing. Going back to start of cycle.

      This is also explaining why equator volcanoes are not impacting this cycle. As prevailing wind direction in middle latitudes is west – east, only middle and high latitude volcanoes are adding dust to snow/ice sheets.

      • Yes I am aware of the volcanic ash hypothesis (ralfellis).
        a) the deposits of volcanic ash will be covered by every fresh snow fall; there may not be a cumulative build up.
        b) We are in a worm interglacial, mantle is depressurised and volcanoes stop erupting, is the polar region summer albedo high enough to restart new ice age?

      • a) it is about total yearly balance. Freshly fallen snow will melt in the spring totally and then layer of previous year dust is added to this year and exposed to sunlight. Layer of dust must be covered by new snow and never melt. This is not happening.

        b) this should be easy to say, just find if permanent snow/ice line is retreating or advancing.

        on the other side, most of current atmospheric content of dust is man made by burning wood, coal and diesel. It is doing work of volcanoes. If you look anytime on actual Earth picture:
        http://www.nnvl.noaa.gov/view/globaldata.html#TRUE
        You see how much of soot is coming from equatorial Africa, India, Indonesia and south east Asia. Fact is that last 10 thousand years there is already influence of man burning woods. This could be reason for this exceptionally long interglacial.
        I’m afraid (or happy) that those deposits will melt most of remaining ice sheets and keep us in warm interglacial.

      • I have no data on volcanic ash or dust deposits to either prove or disprove the hypothesis.
        I have lived in England for some years now, and day to day, week to week and so on, weather reports explain our weather by referring to the polar jet stream. I wondered how atmospheric pressure (usually in vicinity of Iceland) blocking the polar jet stream is controlled. Than I looked at frequency of the volcanic eruption’s and plotted this (needs updating):
        Blue line is the CET reconstructed from it’s 3 fundamental frequencies, to my surprise its oscillations happen to match better the decadal integral of volcanic activity than the CET, the actual data from which it was derived (reason I decided to call it natural variability, rather than the CET reconstruction).
        Any hypothesis requires data (longer the better) to give it some credibility. What is shown above, the 300 years apparent correlation (not necessarily causation) is by no means compelling proof but it could be a good start. If this can be extrapolated back to one or more ice ages, difficult to say. I would only add that there is possibility that the same jet stream plunging N. America an N. Europe into ice age, may have kept Siberia and Alaska clear of the large ice deposits even at depths of the last ice age around 20 Kyr ago.

  14. …and the Southern Ocean is huge sink today because we’ve already started the slow descent to the next glacial period.

    • It is a simplistic view to think of the deep ocean surfaces as being in constant Henry’s Law equilibrium as far as dissolved CO2 is concerned; and likely some other solutes as well. Surface Temperature falls, CO2 dissolves. Surface Temperature rises a little bit, CO2 outgasses into the atmosphere.

      It can’t happen that way.

      The problem is the general lapse rate of near surface water Temperature, probably as a result of the one way transport of solar spectrum radiant energy received from the sun. The long and short ends of the spectrum get peeled away in the shallows, and particularly the UV end is high energy photons. So nearer the surface, the solar heating is greatest, with perhaps a slight Temperature drop right at the surface due to evaporation. The evaporated water vapor is at a much higher Temperature than the bulk of the water, because it is the high energy tail of the Maxwell Boltzmann distribution that provides the easiest escape for H2O molecules, so the average KE of an evaporated water molecule (or group of) is higher than the MB peak (most probable) KE, and moreover the surface water remaining is depleted of the higher KE molecules so the peak of the distribution is shifted lower, and the very surface water becomes colder.

      Now add to the Temperature lapse rate, at least down to the Thermocline, (Izzat a word) the fact that the solubility of CO2 is higher in colder water (Henry’s Law). So you have an upward solubility gradient with increasing depth.

      So a CO2 molecule at a given depth, would be more welcome at a deeper level than it would be at a shallower level. The result is that the random diffusion of CO2 molecules, favors a downward propagation and disfavors an upward travel.

      You have a CO2 pump acting to drive CO2 away from the surface to a greater depth, thus depleting the surface layers of CO2 relative to their Henry’s Law equilibrium concentration.

      So the Temperature gradient and solubility gradient pumps CO2 away from the surface, to greater depths.

      So any small increase in surface Temperature, will not result in immediate outgassing, because the surface water is not saturated with CO2; it is depleted.

      So you have a sort of hysteresis effect, not unlike a diode. CO2 can enter the water somewhat easier than it can exit, due to the Temperature gradient depletion of the surface CO2.

      It’s not a zero sum game. The deep oceans take CO2 out of the atmosphere, and move it to greater depths, and it likely isn’t going to see the light of day for a long time thereafter.

      Yeah I know ocean storm turnovers will mess with the program, but overall, the deep oceans keep on sucking CO2 to its doom.

      Just about the only thing that I know about water, that is even more diabolical than CO2 pumping, is how partly filled gasoline cans that are open to the atmosphere, ensnare H2O from the atmosphere in the can, inhaling H2O during the warm day, which then condenses on the can during the cold night, and promptly drips down into the gasoline, and sinks below it to the bottom of the can, where it is completely immune to subsequent evaporation. That’s why water separating filters are essential on things like gas powered boats. (and sealed gas tanks on cars).

      G

      • George,

        What you describe is largely what happens for the “mixed layer”, the upper few hundred meters of the oceans. That is mostly important for the seasonal exchanges where temperature changes have a large influence.

        There is not much migration of CO2 (and temperature) between the mixed layer and the deep oceans. The main exchanges are by the oceans sink and upwelling zones, which are concentrated in less than 5% of the surface each. Based on 14C and 13C ratio changes, the exchange is about 40 GtC/year, slightly more sink (~3 GtC/year) than source. The mixed layer takes about 0.5 GtC/year out of the atmosphere and is in rapid equilibrium with the CO2 levels of the atmosphere.

        The speed of uptake and release between atmosphere and sink/upwelling places is directly proportional to the partial CO2 pressure difference between water and atmosphere and depends of wind speed, as that makes the exchanges easier as pure diffusion of CO2 is extremely slow.

        Feely e.a. have compiled several million pCO2 measurements all over the oceans which show the main sink and source places:
        http://www.pmel.noaa.gov/pubs/outstand/feel2331/maps.shtml

        That gives the pCO2 differences in summer and winter, while the next section shows the CO2 fluxes over the year 1995.

  15. The evidence “is a long-sought smoking gun that there was increased deep ocean carbon storage when the atmospheric CO2 was lower,” said Sam Jaccard of the University of Bern, Switzerland, the study’s lead author.

    A child could have done better. For such perceived wisdom Nobel Prizes are awarded. To other people.

  16. During the last ice age the sample points would have been under thick sea ice so dissolution of both O2 and CO2 would have been nonexistant to minimal. Put that into your models!
    Too many assumptions for me to agree with this post.

  17. 1. “We are entering climate territory for which we don’t have a good geological analog.”
    2. “The study may hold powerful lessons for today.”

    I’m having trouble reconciling those two sentences. If we don’t have a good analogue, where are the lessons supposed to be coming from?

    I have practised visualising a square circle, but some things are just too much for my poor brain to put together.

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