It comes as not even a tiny surprize that when someone asks “Where does all the CO2 go in an ice age?” that the answer is “The Ocean“.
We already know temperatures rise 800 years before CO2 levels (Caillon 2003), and we know the oceans contain 50 times as much CO2 as the sky. Moreover, basic chemistry tells us that CO2 (like all gases) will dissolve better in cold water, and be released as the water warms. To cap it all off, the deep abyss of the oceans turns over once every millenia or so (which fits loosely with the “lag” between temperature and CO2 levels).
But you would think this new research was solving a deep mystery, rather than confirming what most sane knowledgeable people would expect. Nonetheless, this may be the first detailed study of C13 levels going back 24,000 years.
CO2 was hidden in the ocean during the Ice Age
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 scientists from the Universities of Bern and Grenoble and the Alfred Wegener Institute for Polar and Marine Research in the Helmholtz Association.
According to Schmitt, during the Ice Age more and more carbon dioxide accumulated in the deep ocean, causing the concentration of atmospheric CO2 to drop. Only at the end of the Ice Age was this stored CO2 transported back to the sea surface through changing ocean circulation and thus emitted back into the atmosphere, write the scientists in the scientific journal “Science”.
Right then, but knowing that might muck up a few climate models? If it does, we don’t hear that from the press release or the abstract. Though there is room for the usual caveats about man-made CO2. The paper is behind a paywall, so comments welcome from anyone who can read all the details about the future of those climate models.
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.
Reference: Jochen Schmitt, Robert Schneider, Joachim Elsig, Daiana Leuenberger, Anna Lourantou, Jérôme Chappellaz, Peter Köhler, Fortunat Joos, Thomas F. Stocker, Markus Leuenberger & Hubertus Fischer. Carbon Isotope Constraints on the Deglacial CO2 Rise from Ice Cores. Science Express, 2012