Ice Controls CO2 and Ocean Currents Shift Temperatures

These are a couple of papers that do have the dreaded CO2 in one of them, but refreshingly, more as consequence than as causal. (Though it is a bit ambiguous about cause and effect…)

First up, a paper that claims to find that Antarctic ice growth causes the reduction in CO2 seen at ice age glacial maximum. Essentially that ice covers the place in the Southern Ocean where deep water CO2 can out gas. Not sure I completely buy into the theory (there’s a lot of ocean where, IMHO, CO2 could diffuse and enter / exit the water; and that is not accounted here). But still, quite refreshing to see CO2 as effect, not cause. It does sort of imply a CO2 causal involvement in the write up / description, but not in the description from the referenced paper (that I’ve not got in hand, though…)

The paleoclimate record for the last ice age—a time 21,000 years ago called the “Last Glacial Maximum” (LGM)—tells of a cold Earth whose northern continents were covered by vast ice sheets. Chemical traces from plankton fossils in deep-sea sediments reveal rearranged ocean water masses, as well as extended sea ice coverage off Antarctica. Air bubbles in ice cores show that carbon dioxide in the atmosphere was far below levels seen before the Industrial Revolution.
The researchers focused on the Southern Ocean, which encircles Antarctica—a critical part of the carbon cycle because it provides a connection between the atmosphere and the deep ocean abyss. Ruffled by the winds whipping around Antarctica, the Southern Ocean is one of the only places where the deepest carbon-rich waters ever rise to the surface, to “breathe” CO2 in and out.
This question demanded the use of the field’s accumulated knowledge of ocean physics. Using a mathematical equation that describes the wind-driven ocean circulation patterns around Antarctica, the researchers calculated the amount of water that was trapped under the sea ice by currents in the LGM. They found that the shock to the entire Earth from this added ice cover was massive: The ice covered the only spot where the deep ocean ever got to breathe. Since the sea ice capped these deep waters, the Southern Ocean’s CO2 was never exhaled to the atmosphere.

The researchers then saw a link between the sea ice change and the massive rearrangement of ocean waters that is evident in the paleoclimate record. Under the expanded sea ice, a greater amount of upwelled deep water sank back downward. Southern Ocean abyssal water eventually filled a greater volume of the entire midlevel and lower ocean—lifting the interface between upper and lower waters to a shallower depth, such that the deep, carbon-rich waters lost contact with the upper ocean. Breathing less, the ocean could store a lot more carbon.
A Southern Ocean suffocated by sea ice, the researchers say, helps explain the big drop in atmospheric CO2 during the LGM.

So the description of the ‘finding’ is that ice limited the CO2 flux. Ice first, then flux change. Only the ‘lead in’ sideways hints at CO2 being needed as a kicker to solar changes. And yeah, it looks like it is Yet Another Model… but maybe it’s ‘right enough’…

“This study is an elegant, straightforward explanation that pulls all these pieces together into one place like no one has managed to do before,” says Daniel Sigman, a professor of geological and geophysical sciences at Princeton, who was not involved in the study.
Sigman, who tries to understand carbon fluxes in the last ice age, says that this new framework narrows his focus to a smaller range of possibilities. “What it really does is tune me in to the sea ice and biochemical conditions that I need to see at the Southern Ocean’s surface for the full CO2 drop to be realized.”

And here, a person who read the paper says that it is about understanding what drives CO2 to drop, and that it is ice changing CO2, not CO2 changing ice…

This one finds that ocean currents change up to 1000 years prior to the change of temperatures. The “thaw” came after ocean circulation changed. Gee…. So oceans shift, then temperatures (and per the above ‘ice changes CO2’, one presumes that even later the CO2 changes…)

The Atlantic Ocean at mid-depths may have given out early warning signals – 1,000 years in advance – that the last Ice Age was going to end, scientists report today in the journal Paleoceanography.
Scientists had previously known that at the end of the last Ice Age, around 14,700 years ago, major changes occurred to the Atlantic Ocean in a period known as the Bolling-Allerod interval. During this period, as glaciers melted and the Earth warmed, the currents of the Atlantic Ocean at its deepest levels changed direction.

The researchers have analysed the chemistry of 24 ancient coral fossils from the North Atlantic Ocean to learn more about the circulation of its waters during the last Ice Age. They found that the corals recorded a high variability in the currents of the Atlantic Ocean at mid-depths, around 2km below the surface, up to 1,000 years prior to the Bolling-Allerod interval. The team suggests that these changes may have been an early warning signal that the world was poised to switch from its glacial state to the warmer world we know today, and that the changes happened first at mid-depths.

They use neodymium isotopes in corals and other sea skeletons to indicate source of waters in the currents, thus infer the currents. Nice.

Dr David Wilson, from the Department of Earth Science and Engineering at Imperial College London, said: “The world’s oceans have always been an important barometer when it comes to changes in our planet. Excitingly, the coral fossils we’ve studied are showing us that the North Atlantic Ocean at mid-depths was undergoing changes up to 1,000 years earlier than we had expected. The tantalising prospect is that this high variability may have been a signal that the last Ice Age was about to end.”

The fossil corals analysed by the team come from a species called Desmophyllum dianthus, which are often around 5cm in diameter and look like budding flowers. They typically only live for 100 years, giving the team a rare insight into what was happening to the ocean’s currents during this relatively brief time. Thousands of years ago they grew on the New England Seamounts, which are a chain of undersea mountains approximately 1000km off the east coast of the US, located at mid-depths 2km beneath the surface. This underwater area is important for understanding the North Atlantic’s currents.

So once again we have a cause / effect arrow that points to ocean changes first, then temperature and ice changes. Coupled with the above paper that finds ice controlling CO2, we have the CO2 change last on the list AFTER ocean currents and ice melt. Golly.
And published in 2014.

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About E.M.Smith

A technical managerial sort interested in things from Stonehenge to computer science. My present "hot buttons' are the mythology of Climate Change and ancient metrology; but things change...
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14 Responses to Ice Controls CO2 and Ocean Currents Shift Temperatures

  1. That seems to place the cause of recent increases in atmospheric CO2 as the warmer oceans (and reduced Antarctic Ice) at the time of the Mediaeval Warm Period.

    I suggested that as a possibility many years ago.

    Then, as to the cause of the Mediaeval Warm Period see here:

    so it is back to the sun again.

  2. “The oceans release stored heat intermittently at variable rates depending on the average state of the various global oceanic oscillations at any particular time. The current assumption that the oceanic oscillations are ‘just’ a mechanism for geographically redistributing heat already available to the atmosphere must be wrong. Over periods up to the 1000 year or more length of the Thermohaline Circulation the oceanic heat store should be regarded as an additional heat source that adds or subtracts the effect of earlier solar irradiance (or lack of it) to or from the present day effect of current solar irradiance.”

    from here

    original 2008 version here:

  3. LG says:

    Speaking of ice,
    Some unreported snow news in US media:

    Heavy snow falls in Morocco, Algeria, Tunisia, Lybia.
    Greece, Turkey , Jordan also afflicted.

    Image links:

    Greece Frozen
    Laconia froze

    Madacher yesterday both Ahras market and Ú¤alma and El Tarf, Skikda, Khanshalah, El Eulma Annaba.


    Snow thickness exceeds 20 cm (8 inches) up to 40 cm (16 inches) in the cities of the provinces of Kef and Jendouba, Siliana and Kairouan Kasserine, adding to the suffering and isolation of the residents, especially the poor due to the high prices of wood heating.


    Turkey snowfall

    Italy/Sicily Snows

  4. Gary says:

    E.M., a look at calcite compensation depth data might be informative. To quote from the link below: “The exact value of the CCD depends on the solubility of calcium carbonate which is determined by temperature, pressure and the chemical composition of the water – in particular the amount of dissolved CO2 in the water.”

  5. Quinn the Eskimo says:

    Arm-waving here, but the first article seems odd in that polar waters absorb CO2 whereas upwelling waters in warmer latitudes outgas CO2. This is consistent w/ Henry’s Law, with observations of CO2 flux by Takahishi, thermohaline circulation, and satellite observations of airborne CO2 concentrations, which are on the low end of the scale in polar regions. Therefore, putting a lid on polar waters would seem more likely to inhibit absorption rather than outgassing, eh?

  6. p.g.sharrow says:

    “They found that the shock to the entire Earth from this added ice cover was massive: The ice covered the only spot where the deep ocean ever got to breathe. Since the sea ice capped these deep waters, the Southern Ocean’s CO2 was never exhaled to the atmosphere.”

    The southern oceans would also lose the ability to liberate deep ocean thermal energy due to the stagnation of tropical to polar circulation as well. The tropic oceans would have to liberate their energy as greater amounts of evaporated moisture.
    This sounds to me to be the cause and effect of Ice Ages and interglacials.
    With the expansion of the Antarctic sea ice we may soon get to see a test this theory. pg

  7. R. de Haan says:

    Love this blog. Thanks to you all.

  8. oldfossil says:

    Ferrari Jansen et al “Antarctic sea ice control on ocean circulation in present and glacial climates”at

    It is important to emphasize that we proposed a diagnostic reconstruction that connects sea ice expansion, ocean overturning circulation, and deep water masses. This is different from proposing a prognostic theory for how the ocean transitioned from the modern to a glacial climate.

    Unfortunately the paper was not written for the benefit of a layman like myself and if there is an explanation of how the oceans managed to inhale CO2 while unable to exhale it, I missed it.

  9. craigm350 says:

    Whilst I don’t think the next decade will be conclusive by any means, I think (some of us at least) will get a reasonable broad stroke of a brush idea of what is going on. Inquisitive minds will look beyond the dogmatic bs and see a degree of illumination by pulling together many threads. I would not be surprised if the real insights come from outside the field and that rather than specialisation (master of one but actually knows sod all about tying shoelaces to walk the walk) it’s the piecing together of many threads that, rent seeking aside, lead the way out of the post modern science ignorance abyss/malaise.

    The carbon dioxide just seems to be a specialisation that seems to have performed regulatory capture on our imagination and legislature by narrowly taking effects we have observed by looking in one direction at face value rather than as a whole. It’s like I suppose saying it was the markets that led us away from recession rather than fiat currency. In that I mean we look to the effect that a fire keeps us warm and say all is rosy and toasty in the room forgetting that we just threw some alcohol on the embers for a quick burst but without any actual fuel (wood/coal) the fire remains but dwindling embers and the heated ‘corona’ of warmth is going to shrink.

    I keep going back to Salby’s temps lead CO2 ‘at all timescales’. CO2 is simply not going to add the fuel we need to keep the planet warm because it is an effect not a cause. To me a reasonable assessment – unbeholden to theory – shows the insignificance of carbon dioxide in the larger scale.

    The advance to solar minimum and it’s terrestrial impacts is going to be very interesting indeed.

  10. emsnews says:

    All this ignores the salient fact that ALL ice ages ended suddenly and nearly all have the same length between cycles and follow the exact same pattern of very sudden warm ups and then a strong drop in temperatures which then, very slowly, gradually rise before the next sudden surge upwards.

    CO2 cycles can’t cause this, they are the after effects of this. Ice sheets that send most solar energy reflected back into space during cold cycles all melt very suddenly during warm cycles.

    The only mechanism that can do these pulses of sudden warming is the sun. And the change in climate over the last 12 million years has been very definitely towards cold cycles, not getting warmer and warmer.

  11. p.g.sharrow says:

    @oldfossil;”Unfortunately the paper was not written for the benefit of a layman like myself and if there is an explanation of how the oceans managed to inhale CO2 while unable to exhale it, I missed it.”

    The wind wave interface acts as a fume scrubber that scrubs CO2 out of the air and into solution where it is taken up by ocean plant life that feeds everything that lives in the sea. As things die, the material sinks to the sea bottom, this carries the CO2 from the air to the bottom of the deep oceans where it may stay for great lengths of time along with other nutrients that are carried to the surface in up welling that cause large plankton blooms. Deep sea water is cold and heavy and resists moving to the surface. Deep currents cause the up welling when they encounter the edge of the continental shelf. pg

  12. Chuck L says:

    Dr David Wilson, from the Department of Earth Science and Engineering at Imperial College London, said: “The world’s oceans have always been an important barometer when it comes to changes in our planet. Excitingly, the coral fossils we’ve studied are showing us that the North Atlantic Ocean at mid-depths was undergoing changes up to 1,000 years earlier than we had expected. The tantalising prospect is that this high variability may have been a signal that the last Ice Age was about to end.”

    I wonder what the world’s oceans are telling us now?

  13. E.M.Smith says:

    @Steven Wilde:

    I think many of us have ended up at the same (or very similar) place. It’s the sun. It is spectrum modulated ( shift to more / less IR vs blue& UV) and the distribution of the energy from ocean depths to top of thermosphere. During ‘quite sun’ times, there is far less UV, so thermosphere and upper stratosphere cool / compress height. Lower stratosphere and near poles can have warming events as this squash happens and flow down at the poles increases. Less heat to deep oceans and more as prompt evaporation at the ocean surface (IR / red absorbs in a thin layer, blue / UV goes deep), so more rain and snow and a cooler “loopy jet stream” mode when IR rich, while a more flat flow when UV rich and warm. (Then all those other things you’ve elaborated so well about meridional vs zonal times)

    No idea who was first (though I know you were very early, I’m just not sure if UV as driver was covered earlier by someone else) and outside academic circles, I’m not sure that matters much.

    The oceans are a very large pendulum for heat, sometimes pushed hard and deep with UV, at other times giving that heat back with little new added with shallow IR causing prompt evaporation and precipitation. Period measured in hundreds of years for the oceans, and with various periods from daily to 11 years to 18 years to 60 years to 180 years to… for the solar & lunar tidal events.


    Interesting collection of links. The Warmistas are depending on the tendency for the Average Person to not get news from out of their area and not see the pattern… so swallow the “warmest year ever” garbage. The snows know the truth…


    Yes, there’s a complex interaction with carbonate formation / destruction, temperature cycles, CO2 outgassing from the abyssal depths, volcanic recycle, et. al. It’s the proper realm of geologists, not IR gas guys…


    I think polar absorption is likely driven by “counter flow stripping” of rain and snow in the air, and not by surface / air interface. Basically, I think the capture is more driven by the massive surface area of precipitation that then plunges into the ocean (or makes a snow layer) where outgassing is via ocean surface / air contact.


    That polar oscillation to a much larger S.Polar ice sheet is a far bigger worry, IMHO, than how much “magic gas” is in the air. But like you said, nature is running the experiment and we may get to see ‘soon’…

    @R. de Haan:

    Thanks for the compliment ;-)

    I’ll try to get quantity and quality back up while looking for some kind of paying gig… and it looks like I may have to move back to California as a cost reduction thing. (Still have a house there and can’t support it and a Florida rental at the same time…)

    So there may be another travelogue series in the near future…

    @Old Fossil:

    See my above statement about rain / snow precipitation stripping CO2 from the air (and into run-off and snow banks) vs an ice cover keeping CO2 in the oceans. An ice cap with some kind of water flow into the oceans is a diode of sorts. CO2 can enter in the subglacial meltwater, but not get back out through the ice.

    Thanks for the full paper link. Their graph shows a different thing. Isolation of polar areas leading to an isolated deep pool with an isolated warm pool on top of it (trapped deep water) where at present they have some mixing / communications and thus deep water ventilation. See Fig. 4.

    I like my explanation better ;-) but theirs has potential too.


    I think the theory that CO2 will just shift water content and net do nothing; is most accurate. I’d also hold out my assertion that CO2 is net cooling in the radiative zones (stratosphere / thermosphere) and irrelevant in the non-radiating (or very low radiating) troposphere; as also important.

    It’s clear that the effect of CO2 is not uniform, nor even detectable. So the warmista theory is very wrong.


    At that moment when snow turns to rain under just enough added warmth, the ice gets a rapid melt force going and a large albedo feedback sets in.

    The Milankovich Cycle is largely just identifying that level of persistent solar heating at the North Pole that makes that transition happen.

    It is ONLY during the very brief (geologically speaking) time when all the “more warm north” events align that we exceed that point and the melt starts. (S. Pole doesn’t matter as it never gets warm enough to melt…)

    Going the other way is slower. There’s a mass transport limit on how fast snow can be made from sea evaporation. That snow has a hard time persisting in the warm cycle, and only at the point when it persists through the summer does the feedback to cold get going.

    That point is when the North Polar Ice does NOT melt every so often. Exactly that thing the Warmistas are most paranoid about ( N. Pole melt) is exactly the thing that, if they got their wish, marks the plunge into the next Glacial… As soon as the North Pole freezes, and stays that way through summers, pack your bags and start moving South.

    @Chuck L.:

    Would be nice to know…

    There’s a computed W/m^2 value that’s about 5? Watts away from breakdown into glacial (IFF the calculated value is in fact the threshold). Best guesses range from “now” to “a couple of thousand years” for irrevocable decent into the next glacial.

    I’ve done some work on solar / tidal cycles that I think indicates the next dramatic cold plunge that is strong enough to be non-recoverable ought to be about 300 years from now (though with a significant chance of ‘now’ in the 2020-2050 year range).

    But it isn’t clear and won’t be until it is too late.

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