Paleo-pCO2 Database 324 Million Year Stomata CO2 Data Barclay, R.S.; McElwain, J.C.; Sageman, B.B. Barclay, R.S. McElwain, J.C. Sageman, B.B. earth science/paleoclimate/climate forcing (age,null,null,million years ago,null,climate forcing,null,null,N,null) earth science/paleoclimate/climate forcing (carbon dioxide,bulk atmosphere,null,parts per million,null,climate forcing,null,null,N,from stomatal measurements) earth science/paleoclimate/climate forcing (Global>LATITUDE >LONGITUDE ) The Cretaceous Ocean Anoxic Event 2 (about 94 million years ago) is thought to be linked to extensive volcanism, which triggered a biogeochemical chain of events that eventually led to widespread marine anoxia and a remarkable increase in carbon burial in marine sediments. It has been suggested that the event was accompanied by a substantial decrease in atmospheric CO2 concentrations, but the quantification of the drawdown remains controversial. Here we reconstruct atmospheric CO2 concentrations throughout the ocean anoxic event from counts of the stomata in fossil leaves, and use terrestrial carbon isotopes to link the reconstruction to marine records of the event. We find that before the onset of ocean anoxia, atmospheric CO2 concentrations increased by 20% over background levels of 370 +100/-70 ppm. This was part of a long-term rise in atmospheric CO2 levels, presumably caused by volcanism, which reached a peak of 500 +400/-180 ppm. However, two pulses of extensive carbon burial during the ocean anoxic event, as indicated by positive carbon isotope excursions, are associated with decreased atmospheric CO2 concentrations. We conclude that the sequestration of marine organic carbon led to a decrease in atmospheric CO2 concentration of up to 26% during Ocean Anoxic Event 2. STUDY NOTES: Paleo-CO2 derived from fossil plant stomata, contributed to the Paleo-pCO2 Database NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Barclay, R.S. Investigator : McElwain, J.C. Investigator : Sageman, B.B. 2018-05-25 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/24210 https://www1.ncdc.noaa.gov/pub/data/paleo/climate_forcing/trace_gases/Paleo-pCO2/barclay2010stomata.xlsx https://www1.ncdc.noaa.gov/pub/data/paleo/climate_forcing/trace_gases/Paleo-pCO2/barclay2010stomata.txt https://www1.ncdc.noaa.gov/pub/data/paleo/climate_forcing/trace_gases/Paleo-pCO2/barclay2010stomata.xlsx https://www1.ncdc.noaa.gov/pub/data/paleo/climate_forcing/trace_gases/Paleo-pCO2/barclay2010stomata.txt English https://www.ncdc.noaa.gov/paleo/study/24210 https://www1.ncdc.noaa.gov/pub/data/paleo/climate_forcing/trace_gases/Paleo-pCO2/barclay2010stomata.xlsx https://www1.ncdc.noaa.gov/pub/data/paleo/climate_forcing/trace_gases/Paleo-pCO2/barclay2010stomata.txt Richard S. Barclay, Jennifer C. McElwain, Bradley B. Sageman2010Carbon sequestration activated by a volcanic CO2 pulse during Ocean Anoxic Event 2Nature Geoscience3205-20810.1038/ngeo757https://www.nature.com/articles/ngeo757 David R. Greenwood, Mark J. Scarr, David C. Christophel2003Leaf stomatal frequency in the Australian tropical rainforest tree Neolitsea dealbata (Lauraceae) as a proxy measure of atmospheric pCO2Palaeogeography, Palaeoclimatology, Palaeoecology1963-4375-39310.1016/S0031-0182(03)00465-6 https://www.sciencedirect.com/science/article/pii/S0031018203004656 Wolfram M. Kürschner, Zlatko Kvacek, and David L. Dilcher2008The impact of Miocene atmospheric carbon dioxide fluctuations on climate and the evolution of terrestrial ecosystemsProceedings of the National Academy of Sciences105449-45310.1073/pnas.0708588105http://www.pnas.org/content/105/2/449 Robin Y. Smith, David R. Greenwood, James F. Basinger2010Estimating paleoatmospheric pCO2 during the Early Eocene Climatic Optimum from stomatal frequency of Ginkgo, Okanagan Highlands, British Columbia, CanadaPalaeogeography, Palaeoclimatology, Palaeoecology2931-2120-13110.1016/j.palaeo.2010.05.006https://www.sciencedirect.com/science/article/pii/S003101821000283X Johan Van Der Burgh, Henk Visscher, David L. Dilcher, Wolfram M. Kürschner1993Paleoatmospheric Signatures in Neogene Fossil LeavesScience26051151788-179010.1126/science.260.5115.1788http://science.sciencemag.org/content/260/5115/1788 Yuqing Wang, Arata Momohara, Li Wang, Julie Lebreton-Anberrée, Zhekun Zhou2015Evolutionary History of Atmospheric CO2 during the Late Cenozoic from Fossilized Metasequoia NeedlesPLoS ONE10710.1371/journal.pone.0130941http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0130941 Beerling, D.J.2002Low atmospheric CO2 levels during the Permo- Carboniferous glaciation inferred from fossil lycopsidsProceedings of the National Academy of Sciences992012567-1257110.1073/pnas.202304999http://www.pnas.org/content/99/20/12567 START YEAR: 324000000 cal yr BP * END YEAR: 950000 cal yr BP -180 -90 180 90