Mauna Loa CO2 vs Ice Core CO2 data?

Does data from CO2 Observatories match data about CO2 from Ice Cores, or do they contradict each other?

Anyone have any snazzy looking graphs (or links to)?

Quote:

Originally Posted by quitenormal 

Does data from CO2 Observatories match data about CO2 from Ice Cores, or do they contradict each other?

 

Anyone have any snazzy looking graphs (or links to)?

The time constants are different so there is very little overlap.  Mauna Loa starts in the 1950's, which is just about when the latest ice cores end (most are far earlier, like a few thousand years). 

The different ice core datasets from the northern and southern hemisphers pretty much agree with each other though. 

Thanks. Are there any other re constructions of CO2 content pre 1950, which back up the Ice Core data?

Quote:

Originally Posted by quitenormal 

Thanks. Are there any other re constructions of CO2 content pre 1950, which back up the Ice Core data?

Yes, lots.  The best place to start looking at what is available is in the IPCC AR4, Chapter 6, where they deal with paleoclimate science.  If you are an IPCC hater, then you likely won't believe a word they say, but it is a good review of the relevant science. There was also a Nature paper I saw once, but since most people can't access those online I'll let you dig it up for yourself (google "ice core co2 comparisons" and scroll through the hits a bit).  

The ice core data is backed up by sediment records from the oceans, corals, and terrestrial proxies (the details of which I've forgotten but are available in the IPCC report. 

I'm not an IPCC hater gcnp58. I'd just prefer a nice, easy little graph that I link people to in debates, rather than a lengthy scientific report. You don't have any of those do you?

Quote:

Originally Posted by quitenormal 

I'm not an IPCC hater gcnp58. I'd just prefer a nice, easy little graph that I link people to in debates, rather than a lengthy scientific report. You don't have any of those do you?

Here's an example for isotopic ratios:

http://www.gisp2.sr.unh.edu/DATA/Bender.html

Most of the ice core data is available for download here:

http://www.ncdc.noaa.gov/paleo/icecore/current.html

You could plot it yourself and post the results here.  :-)

There is this plot from Caspar Ammanns at NCAR:

http://www.cgd.ucar.edu/research/profiles/images/2009/ammann1.jpg

(from this paper:  Gao, C., A. Robock and C. Ammann. 2008: Volcanic forcing of climate over the past 1500 years: An improved ice core-based index for climate models. Journal of Geophysical Research-Atmospheres, 113, D23111, doi:10.1029/2008JD010239.)

Quote:

Originally Posted by gcnp58 

 

 

 

You could plot it yourself and post the results here.  :-)

 

I could, except that what I'm after is a comparison between ice core records and some other historical CO2 proxy. While the links you've given me seem to show comparison between ice cores, and other ice cores. As I said: Are there any other re constructions of CO2 content pre 1950, which back up the Ice Core data? 

Quote:

Originally Posted by quitenormal 

 

I could, except that what I'm after is a comparison between ice core records and some other historical CO2 proxy. While the links you've given me seem to show comparison between ice cores, and other ice cores. As I said: Are there any other re constructions of CO2 content pre 1950, which back up the Ice Core data? 

You're asking for something that I don't believe exists.  There aren't any good proxies for atm. CO2 concentrations aside from ice cores.  Stomatal CO2 estimates are notoriously imprecise (and have been derived for the most part with the ice core records to begin with), and the other estimates from paleo CO2 come from models like GEOCARB (google "geocarb berner").  So, while you can find these comparisons in the literature, they don't really tell you much since the ice core data is so much better than other estimates.  What has been done a lot is to compare isotopic information from ice cores with isotopic data from sediments, and in those cases there is very good agreement.  The agreement of the isotope records gives very high assurance that the CO2 records are also correct.  Furthermore, the agreement between ice core data from different sites, especially the interhemispherical agreement, provides further evidence the CO2 data are correct. 

But you can't find a plot of CO2 comparison between ice core and something else because there isn't really anything else.  If there were, and the agreement was not good, there would be hundreds of such plots on every nitwit climate skeptic website out there.  But there isn't because the ice core data is as certain as anything can be in science. 

Example of a paper comparing sediment isotope records to ice core isotope data:

Deep sea sedimentary analogs for the Vostok ice core.     Mortyn, P. Graham; Charles, Christopher D.; Ninnemann, Ulysses S.; Ludwig, Kristen; Hodell, Dvid A.    Scripps Institution of Oceanography,  La Jolla,  CA,  USA.    Geochemistry, Geophysics, Geosystems  (2003),  4(8),  No pp. given.  Publisher: American Geophysical Union,  CODEN: GGGGFR  ISSN: 1525-2027.  http://www.agu.org/journals/gc/gc0308/2002GC000475/2002GC000475.pdf  Journal; Online Computer File  written in English.    CAN 140:29728    AN 2003:742709    CAPLUS 

Abstract:  Many applications of the Vostok ice core depend critically on the ability to make stratigraphic ties to marine records in the adjacent Southern Ocean.  Oxygen isotopic records are presented for high accumulation-rate sites in the South Atlantic sector of the Southern Ocean, collected for the purpose of complementing the recently extended .delta.D record from the Vostok ice core.  The combination of several planktonic foraminiferal .delta.18O record from the Vostok ice core.  The combination of several planktonic foraminiferal .delta.18O records from northern subantarctic piston cores demonstrates that all of the millennial-scale oscillations-expressed in the Vostok ice core over the last 60 kyr are also present in marine records.  The observations also support the assumption that the millennial-scale oscillations common to both marine and ice archives are synchronous, thus providing a rationale for extending the marine-ice core comparison through the last 400 kyr, making use of a marine drilled core (ODP Site 1089).  By aligning the phase of these common abrupt events, the Vostok chronol. is related to an orbitally tuned marine sediment chronol. - a refinement that allows examn. of a variety of paleoclimatol. issues such as the relationship between deep ocean variability and Antarctic polar climate.  For example, this exercise suggests that, over at least the 4 major deglaciation events, the primary (orbital scale) changes in the chem. and, most likely, the temp. of the deep Southern ocean were synchronous with changes in atm. pCO2 and polar air temps.  Also, the deuterium excess in the ice core resembles marine (foraminiferal) .delta.13C records and the deuterium excess is synchronous with an "anomalous" foraminiferal .delta.18O signal (the residual between normalized versions of Vostok .delta.D and foraminiferal .delta.18O).  These observations demand a tight link between the Vostok isotopic record and the air-sea interaction of the subantarctic zone.