Paleo-pCO2 Database Early Cenozoic Liverwort-Bryocarb CO2 Data Royer, D. Royer, D. earth science/paleoclimate/climate forcing (notes,null,null,null,null,climate forcing,null,null,C,stratigraphic level) earth science/paleoclimate/climate forcing (sample identification,null,null,null,null,climate forcing,null,null,C,sample name) earth science/paleoclimate/climate forcing (notes,null,null,null,null,climate forcing,null,null,C,sample repository) earth science/paleoclimate/climate forcing (notes,null,null,null,null,climate forcing,null,null,C,how was age determined) earth science/paleoclimate/climate forcing (age,null,null,million years ago,null,climate forcing,null,null,N,null) earth science/paleoclimate/climate forcing (longitude,null,null,degree east,null,climate forcing,null,null,N,null) earth science/paleoclimate/climate forcing (notes,null,null,null,null,climate forcing,null,null,C,person who entered data) earth science/paleoclimate/climate forcing (carbon dioxide,null,unspecified error lower bound,parts per million,null,climate forcing,null,null,N,null) earth science/paleoclimate/climate forcing (notes,null,null,null,null,climate forcing,null,null,C,family) earth science/paleoclimate/climate forcing (notes,null,null,null,null,climate forcing,null,null,C,geologic formation) earth science/paleoclimate/climate forcing (notes,null,null,null,null,climate forcing,null,null,C,CO2 type) earth science/paleoclimate/climate forcing (notes,null,null,null,null,climate forcing,null,null,C,what is the uncertainty range?) earth science/paleoclimate/climate forcing (age,null,unspecified error upper bound,million years ago,null,climate forcing,null,null,N,null) earth science/paleoclimate/climate forcing (notes,null,null,null,null,climate forcing,null,null,C,date of data entry) earth science/paleoclimate/climate forcing (notes,null,null,null,null,climate forcing,null,null,C,genus) earth science/paleoclimate/climate forcing (notes,null,null,null,null,climate forcing,null,null,C,age scale) earth science/paleoclimate/climate forcing (carbon dioxide,null,unspecified error upper bound,parts per million,null,climate forcing,null,null,N,null) earth science/paleoclimate/climate forcing (notes,null,null,null,null,climate forcing,null,null,C,species) earth science/paleoclimate/climate forcing (age,null,unspecified error lower bound,million years ago,null,climate forcing,null,null,N,null) earth science/paleoclimate/climate forcing (notes,null,null,null,null,climate forcing,null,null,C,general notes) earth science/paleoclimate/climate forcing (notes,null,null,null,null,climate forcing,null,null,C,doi) earth science/paleoclimate/climate forcing (carbon dioxide,null,null,parts per million,null,climate forcing,null,null,N,reported mean CO2) earth science/paleoclimate/climate forcing (notes,null,null,null,null,climate forcing,null,null,C,citation) earth science/paleoclimate/climate forcing (notes,null,null,null,null,climate forcing,null,null,C,what is the distribution of uncertainties?) earth science/paleoclimate/climate forcing (latitude,null,null,degree north,null,climate forcing,null,null,N,null) earth science/paleoclimate/climate forcing (Global>LATITUDE >LONGITUDE ) The relationship between atmospheric carbon dioxide (CO2) and climate in the Quaternary period has been extensively investigated, but the role of CO2 in temperature changes during the rest of Earth's history is less clear. The range of geological evidence for cool periods during the high CO2 Mesozoic 'greenhouse world' of high atmospheric CO2 concentrations, indicated by models and fossil soils, has been particularly difficult to interpret. Here, we present high-resolution records of Mesozoic and early Cenozoic atmospheric CO2 concentrations from a combination of carbon-isotope analyses of non-vascular plant (bryophyte) fossils and theoretical modelling. These records indicate that atmospheric CO2 rose from ~420 p.p.m.v. in the Triassic period (about 200 million years ago) to a peak of ~1,130 p.p.m.v. in the Middle Cretaceous (about 100 million years ago). Atmospheric CO2 levels then declined to ~680 p.p.m.v. by 60 million years ago. Time-series comparisons show that these variations coincide with large Mesozoic climate shifts, in contrast to earlier suggestions of climate-CO2 decoupling during this interval. These reconstructed atmospheric CO2 concentrations drop below the simulated threshold for the initiation of glaciations on several occasions and therefore help explain the occurrence of cold intervals in a 'greenhouse world'. STUDY NOTES: Liverwort-Bryocarb paleo-CO2 data from Fletcher et al. 2008 and Royer et al. 2012 contributed to the Paleo-pCO2 Database. NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Royer, D. 2017-12-17 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/23250 https://www1.ncdc.noaa.gov/pub/data/paleo/climate_forcing/trace_gases/Paleo-pCO2/fletcher2008liverwort.xlsx https://www1.ncdc.noaa.gov/pub/data/paleo/climate_forcing/trace_gases/Paleo-pCO2/fletcher2008liverwort.txt https://www1.ncdc.noaa.gov/pub/data/paleo/climate_forcing/trace_gases/Paleo-pCO2/fletcher2008liverwort.xlsx https://www1.ncdc.noaa.gov/pub/data/paleo/climate_forcing/trace_gases/Paleo-pCO2/fletcher2008liverwort.txt English https://www.ncdc.noaa.gov/paleo/study/23250 https://www1.ncdc.noaa.gov/pub/data/paleo/climate_forcing/trace_gases/Paleo-pCO2/fletcher2008liverwort.xlsx https://www1.ncdc.noaa.gov/pub/data/paleo/climate_forcing/trace_gases/Paleo-pCO2/fletcher2008liverwort.txt Benjamin J. Fletcher, Stuart J. Brentnall, Clive W. Anderson, Robert A. Berner, David J. Beerling2008Atmospheric carbon dioxide linked with Mesozoic and early Cenozoic climate changeNature Geoscience143-4810.1038/ngeo.2007.29https://www.nature.com/articles/ngeo.2007.29 D.L. ROYER, M. PAGANI and D.J. BEERLING2012Geobiological constraints on Earth system sensitivity to CO2 during the Cretaceous and CenozoicGeobiology104298-31010.1111/j.1472-4669.2012.00320.xhttp://onlinelibrary.wiley.com/wol1/doi/10.1111/j.1472-4669.2012.00320.x/abstract START YEAR: 58400000 cal yr BP * END YEAR: 51900000 cal yr BP -180 -90 180 90