CO2 was hidden in the ocean during the Ice Age: study

Why did the atmosphere contain so little carbon dioxide (CO2) during the last Ice Age 20,000 years ago? Why did it rise when the Earth's climate became warmer? Processes in the ocean are responsible for this, says a new study based on newly developed isotope measurements. This study has now been published in the scientific journal Science by German scientists from the Universities of Bern and Grenoble and the Alfred Wegener Institute for Polar and Marine Research in the Helmholtz Association.

Around 20,000 years ago, the atmospheric CO2 concentration during the was distinctly lower than in the following . Measurements from Antarctic ice cores showed this already two decades ago. An international team of glaciologists thereafter looked even further back in time. The found that this close connection between carbon dioxide and temperature has existed over the past 800,000 years: with low during the Ice Ages and higher CO2 values during warm periods. Now they tried to answer also the question as to where the carbon dioxide was hidden during the Ice Ages and how it got back into the atmosphere at their ends.

"We have now been able to identify processes in the ocean which are connected to the observed rise in CO2", says Dr. Jochen Schmitt, lead author of the recently published study and researcher at the Oeschger Centre for Climate Change Research at the University of Bern. According to Schmitt, during the more and more carbon dioxide accumulated in the , causing the concentration of atmospheric CO2 to drop. Only at the end of the Ice Age was this stored CO2 transported back to the through changing and thus emitted back into the atmosphere, write the scientists in the scientific journal "Science".

A new method for isotope measurements has now made it possible for the first time "to reliably decode the fingerprint of the CO2 preserved in the ice", explains Schmitt. He and his colleague Prof. Hubertus Fischer initially developed these new isotope measurement methods for ice cores at the Alfred Wegener Institute for Polar and Marine Research and further refined them in many years of research work after moving to Bern. Using the new method the glaciologists extract the air trapped in the ice core completely and the CO2 contained in the air is thoroughly cleaned. The different isotopes of the CO2 are analysed in a mass spectrometer and from this data the origin of the carbon dioxide can be derived.

Researchers suggested back in the eighties that this puzzle could be solved using an isotopic "CO2 fingerprint". However, it had so far not been possible to make a precise analysis of the trapped in the Antarctic ice due to the technical hurdles. The glaciologists and the climate researchers at the Universities of Bern and Grenoble and of the Alfred Wegener Institute for Polar and Marine Research have now managed a breakthrough with their study.

Development of Future Scenarios

"The new data have already enabled us to revise and improve a few theories about the possible reasons for CO2 fluctuations. Measurement data from the past enable us to gain a clearer idea about how the climate must have looked at the end of the Ice Age", says Jochen Schmitt. And now the data must be compared with the results from climate models to verify and further develop the models. "In addition to the scientific curiosity about how our Earth functioned in the past, the main question to be asked is how the Earth will develop under the influence of man", explains Jochen Schmitt. These are important scenarios for the future because the CO2 content in the atmosphere has never been anywhere near as high over the past 800,000 years as today, says the climate researcher.


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Carbon cycling was much smaller during last ice age than in today's climate: study

Citation: CO2 was hidden in the ocean during the Ice Age: study (2012, March 29) retrieved 20 July 2019 from https://phys.org/news/2012-03-co2-hidden-ocean-ice-age.html
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Mar 29, 2012
The coral bleaching should be therefore prominent during the Ice Age, because the concentration of carbon dioxide in marine water was supposedly high this time. But the corals managed to survive the Ice Age without problem.

Mar 29, 2012
Wait ... more CO2 flows out of the oceans when they warm?

Seems quite obvious that warmth results in more CO2, not the other way around.

Mar 29, 2012
It's AGW! All them cavemen with their campfires have ruined the world! Quick! We must work to revert the world to its naturally frozen state! Notify the IPCC! LOL

One cavemen to another: I pee, see, see?
Caveman 2 response: Good, use pee, put out fire. Save world from climate change.


Mar 29, 2012
@NotParker - it has been well known for over a century that cold water can hold more dissolved gas of almost any kind.

CO2 warms the earth's surface, including the oceans.
The warmer oceans then hold less CO2, so they release CO2.
That CO2 further warms the earth's surface, including the oceans.
This is one of the positive feedbacks that amplifies the effect of CO2 (a bigger amplification being water vapor).

It is also why CO2 increases typically both precedes AND follow temperature increases.

Mar 30, 2012
The cooler the oceans the more they absorb CO2. The more CO2 they absorb, the cooler they become. The cooler they become, the more CO2 they absorb.

This is one of the positive feedback mechanisms that amplify the effects of CO2 on Global Cooling.

It`s also why CO2 decreases typically both precede AND follow temperature decreases.

Mar 31, 2012
@NotParker - it has been well known for over a century that cold water can hold more dissolved gas of almost any kind.

CO2 warms the earth's surface, including the oceans.
The warmer oceans then hold less CO2, so they release CO2.
That CO2 further warms the earth's surface, including the oceans.
This is one of the positive feedbacks that amplifies the effect of CO2 (a bigger amplification being water vapor).

It is also why CO2 increases typically both precedes AND follow temperature increases.
Then however did it get cold, in the first place?


Mar 31, 2012
The cooler the oceans the more they absorb CO2. The more CO2 they absorb, the cooler they become. The cooler they become, the more CO2 they absorb.

This is one of the positive feedback mechanisms that amplify the effects of CO2 on Global Cooling.

It`s also why CO2 decreases typically both precede AND follow temperature decreases.
Then however did it get warm again?

Mar 31, 2012
It is well known and has been for a very long time, that the current spate of ice ages are the result of slow and predictable changes in the earths rotational and orbital parameters

How is it that you don't know this?
All you're saying here is global warming and cooling happens in spite of atmospheric CO2 content. How does that further your AGW argument/agenda?

And while you're at it, please explain how a decade of cooling is actually "accelerated" global warming.

Mar 31, 2012
Then however did it get cold, in the first place?

@NotParker - if you are going to be commenting, please do a bit of reading on the subject first... wikepedia at the very minimum - start with this: http://en.wikiped...h_cycles

As for how it gets warm again, that's actually a much better question. Once warming starts the process is the feedbacks (of which CO2 has been discussed above), but the triggering mechanism details are still being worked out. There have been some papers recently on why ice ages have several pulses of advancing ice and then a sudden collapse of the ice sheets, so we are getting closer to detailed answers, but it is still a 'hot topic' in research.

Mar 31, 2012
Why do you elect to leave out the reason that I provided to you for the cause of the ice ages?
Don't blame the messenger. You're the one that excluded CO2 as the cause.

Like a true idiot, you asked for the cause, and are now ignoring the cause.
How is pointing out the cause not being related to atmospheric CO2 content, ignoring it?

If you weren't such a dishonest retard, you might have asked yourself what changed in the Earth's climate system that caused the Earth to become sensitive to Milankovitch cycles in the first place.
Okay. What changed in the Earth's climate system that caused the Earth to become sensitive to Milankovitch cycles in the first place?

And there you will find that CO2 is in part responsible.
But you just said it wasn't. How does that work?

If you're correct, we'd never have an iceage, 'cause CO2 would prevent it. The facts state otherwise.

Mar 31, 2012
Ignoring facts is a characteristic of a dishonest denialist like yourself.
You mean like you ignoring there's been no net global warming for 14 years, and the sea levels are falling, and a decade of cooling isn't really "accelerated" global warming?

As a honest man, I don't state or consider only those facts that support my position. Unlike you, I go where the evidence leads, rather than torturing the evidence to take me where my conservative ideology demands that I go.
LOL. You're a laugh riot there VDtard. You SPECIALIZE in ignoring data.

I am a clear minded slave to reality.
Stop it! You're making my sides hurt!

Please, for posterity, tell us in your "reality" how a decade of global cooling is actually "accelerated" global warming.

You on the other hand are delusional and suffering from a deep mental illness that stems from your political ideology.
Says the Green Party nut-job.


Mar 31, 2012
Primarily it was due to a reduction ...


In your IQ.

Ice ages have been occurring for 600 million years. The most recent ones are probably because of continental shift that allows cold water to flow.

Antarctica split off from Gondwanaland and moved south about 20-30 million years ago.

Mar 31, 2012
With the sun as hot as it is now, it took the circumpolar current AND lower CO2 to start this series of ice ages, plus a Milankovitch-cycle cooling to start a given ice age.

Mar 31, 2012
You are not a messenger, but a failed consumer of knowledge.

And that is why you ignore the answer to the very question you asked. Ice ages are caused by slowly evolving changes in the orbital and rotational parameters of the earth.
Again, all you're saying is CO2 has nothing to do with climate.

If you had done such a thing. But you did not do so. I did.
And there you again confirm, CO2 has nothing to do with climate change!

And now you are lying about it.
Says the master liar.

The current changes in global temperature are not caused by the glacially slow changes in the orbital and rotational parameters of the earth which take tens of thousands of years to manifest themselves.
Uh, hasn't it been tens of thousands of years since our last iceage?

The primary cause now known to science for almost 150 years is the changing concentration of CO2.
Then why has "global warming" stalled out? Heck, it's been cooling for over a decade!

Mar 31, 2012
"What changed in the Earth's climate system that caused the Earth to become sensitive to Milankovitch cycles in the first place?"

Primarily it was due to a reduction in atmospheric CO2 levels from a state where variations in insolation that were too small to have significantly altered the planets ice balance, to a state where those same insolation changes were large enough, at which point positive feedbacks from the reflective surface of new ice - and other positive feedbacks - amplified the effect, producing ice ages.
Then however did it get warm again?

Mar 31, 2012
Regular ice ages have only been been occurring for 2.5 million years or so.


"At least seven ice ages have been recognized. At least four of them are considered significant because of the extent of their glaciation or because they lasted for an extremely long time:

about 2 million years ago to the presentthe Quaternary Ice Age

350 to 250 million years agothe Karoo Ice Age

800 to 600 million years agothe Cryogenian (or Sturtian-Varangian) Ice Age

2400 to 2100 million years agothe Huronian Ice Age."

VD has no perspective at all.

Apr 02, 2012
Yes, yes, lets insult and denigrate because differences of opinion certainly can't be allowed. And certainly wining over those of differing opinions is far less important than self satisfaction and ego stroking of indulging in moral indignation and superiority. Certainty no one would be put off or take an antagonistic position because of the insulting tone taken by its proponent. Naaa...

Apr 02, 2012
Increasing insolation caused by the same periodic changes that caused the initial decrease in insoltion warmed the ocean and the unfrozen land surface pushing back the equilibrium point for the snow and ice. Warm ocean water outgassed CO2 stored from the ice age and the resulting warming caused even more warming and more melting.

Warming also caused atmospheric methane levels and eventually water vapour levels to increase, warming the atmosphere more, and causing the glaciers to retreat to the positions they held at the end of the current glacial period 12,000 years ago.

Typically, as has been the case in this interglacial, temperatures overshoot the equilibrium point and then slowly cool until the next glacial period. This cooling is punctuated by various anomalies of various origins.
All you're doing is stating other factors caused the warming and cooling periods, and CO2 just went along for the ride.

Apr 02, 2012
Then why has "global warming" stalled out? - Uba


Probably because it hasn't.
But you already admitted it has. So are you lying now, or then?

Apr 03, 2012
Are there dead spots in the ocean circulation where there would still be water undisturbed from the ice age, or at least so slow moving it is still around with measurable composition?

Apr 03, 2012
Until we got here it did. Increased atmosheric CO2 USED to be a result of a warming climate that acted as a feedback to continue the warming cycle, and allow other feedbacks to initiate to amplify warming further. Our CO2 input has changed the entire nature of climate change because WE have initiated a proven climate forcing by artificially elevating it.
It is a proven fact that CO2 is a GHG.
Nobody disputes the nature of GHG's.
Over the last 800,000 years we have had numerous glaciations and warming events during which time CO2 PPM never rose above 280.
Todays level is 393 PPM and rising. To say that this has no effect is wilful ignorance because to do so is to claim you do not believe things which science has proven beyond a reasonable doubt.
We've had no net global warming for 14 years. If CO2 had such a strong effect, how come there is no current correlation between continuously rising CO2 levels, and global temperature?


Apr 04, 2012
No global warming for 15 years.

http://climaterea...?id=9389

Satellite data has March .11C warmer than 1980. Last month if was colder than 1980.

Yet CO2, the amazingly impotent limp GHG has had no effect for 15 years and is so patheticly limp and impotent it never caused any warming. It was all natural.

Apr 04, 2012
coincidentally "stalled" at a plateau higher than the 50 years preceding the start year


1) Satellites were not measuring temperature 50 years ago ... or 68.

2) But ... http://www.cru.ue...t3gl.txt

Jan 2012 0.218

Jan 1944 0.240

It was warmer 68 years ago.

And within .003C 70 years ago.

Jan 1942 0.215

Apr 04, 2012
There are many factors that can alter the earth's temperature. CO2 concentration is just one of them.

During the transition from glacial to interglacial periods, CO2 acts as an amplifier to enhance the warming effect of the change in solar insolation through it's slow release from warming oceans, and it's slow re-uptake from cooling oceans (glacial onset)

But right now CO2 is in the driver's seat as the observed warming runs counter to the ongoing solar insolation changes.
What warming? There's been no net warming for 14 years!

It isn't rocket science. It is K-8 Grade school science.
Then why are you always getting it wrong?

It is a sign of some deep mental illness that you spend hours out of your day lying about it.
The liar is clearly you. Answer the question I asked:

We've had no net global warming for 14 years. If CO2 had such a strong effect, how come there is no CURRENT correlation between continuously rising CO2 levels, and global temperature?

Apr 04, 2012
UbVonTard has publicly admitted that he is a liar and intends to continue to lie regarding Global Warming for the rest of his life.
Just saying this proves you're the liar.

It is mental illness on his part, and worthy only of denigration.
Say the self admitted, murderous eco-terrorist.

Apr 22, 2012
It is well known and has been for a very long time, that the current spate of ice ages are the result of slow and predictable changes in the earths rotational and orbital parameters

How is it that you don't know this, Tard Boy?

"Then however did it get cold, in the first place?" - UbVonTard
"Then however did it get warm again?" - UbVonTard



VD The Troll,
Yes you are accidentally correct once again...
http://www.youtub...=related

Apr 22, 2012
The gravitational facts of other planets cause the ellipse of our orbit to slowly spin around the Sun. It takes about 112,000 years for the ellipse to revolve once relative to fix stars when considered together with two forms of perception add. And it takes about 21,000 years for the solstice to go from aphelion to aphelion. The dates of the perihelion and aphelion advanced each year on the Sun core an average of one day per 58 years. The eccentricity of Earth orbit is a measure of how round or how oval shape is. Over thousands of years the eccentricity of orbit varies as a result of gravitational attractions among the planets primarily Jupiter and Saturn. The orbital eccentricity cycles with a period of 100,000 years. As the eccentricity of the orbit evolves the semi major axis of orbital ellipse remains unchanged, so the length of the sidereal year remains unchanged. As the earth travels in its orbit the duration of seasons depends on eccentricity of the orbit. To be continued..

Apr 22, 2012
When the orbital eccentricity extreme, the seasons that occur on the far side of the orbit are substantially longer in duration. In addition the axial perception theres the axial tilt. The angle of Earth rotational axis makes with its orbital plane. Its currently about 23.4 degrees and is declining. This tilt varies from 22.1 degrees to 24.5 degrees. It makes one complete tilt and back every 41,000 years. This changing tilt is directly related to Ice Ages on Earth. The last max tilt occurred in 8700 BC and the next min tilt will happen in 11,800 AD. The inclination of earths orbit drives up/down relative to the present orbit having a period of about 70,000 years. Orbit also moves relative to the orbit of other planets as well. to be continued...

Apr 22, 2012
By calculating the plane of unchanged total angular momentum of the solar system we can define the overall plane called the invariable plane. It is approximately the orbital plane of Jupiter. The inclination of earths orbit has a 100,000 year cycle relative to the invariable plane. This 100.000 years cycle closely matches the 100,000 pattern of ice ages.
A year on earth is directly determined by all the various orbital motions of the earth. So if someone tells you how many years old they are, you might ask them is that sidereal, tropical or anomalous years. End.

Apr 22, 2012
Regular ice ages have only been been occurring for 2.5 million years or so.

"Ice ages have been occurring for 600 million years." - Parker Tard

There have been other periods of glaciation, but they were not periodic, and are associated with lowered levels of atmospheric CO2.

In the distant past when the continents were fused into a super-continent ocean circulation patterns differed from today. The sun was dimmer, the Antarctic had no land based ice cap, Greenland didn't exist, and the surface of the earth prior to 500 million years was barren rock without plant or animal life.

The causes of rare periods of glaciation at that time or earlier were not what is causing the regular onset of glacial periods that we see today.

Poor ignorant Parker Tard.

how comes 2.5 million years?

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