{"NOAAStudyId":"24030","contactInfo":{"address":"325 Broadway, E/NE31","city":"Boulder","constraints":"Please cite original publication, online resource, dataset and publication DOIs (where available), and date accessed when using downloaded data. If there is no publication information, please cite investigator, title, online resource, and date accessed. The appearance of external links associated with a dataset does not constitute endorsement by the Department of Commerce/National Oceanic and Atmospheric Administration of external Web sites or the information, products or services contained therein. For other than authorized activities, the Department of Commerce/NOAA does not exercise any editorial control over the information you may find at these locations. These links are provided consistent with the stated purpose of this Department of Commerce/NOAA Web site.","country":"USA","dataCenterUrl":"https://www.ncdc.noaa.gov/data-access/paleoclimatology-data","email":"paleo@noaa.gov","fax":"303-497-6513","longName":"National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce ","phone":"303-497-6280","postalCode":"80305-3328","shortName":"DOC/NOAA/NESDIS/NCEI","state":"CO","type":"CONTACT INFORMATION"},"contributionDate":"2018-05-09","dataPublisher":"NOAA","dataType":"CLIMATE FORCING","dataTypeInformation":"https://www.ncdc.noaa.gov/data-access/paleoclimatology-data/datasets/climate-forcing","difMetadataLink":"http://www1.ncdc.noaa.gov/pub/data/metadata/published/paleo/dif/xml/noaa-forcing-24030.xml","doi":null,"earliestYearBP":17110000,"earliestYearCE":-17108050,"entryId":"noaa-forcing-24030","funding":[{"fundingAgency":"Natural Environment Research Council (NERC)","fundingGrant":"NE/I006176/1, NE/I006427/1, NE/I006168/1"}],"investigators":"Greenop, R.; Foster, G.L.; Wilson, P.A.; Lear, C.H.","mostRecentYearBP":15540000,"mostRecentYearCE":-15538050,"onlineResourceLink":"https://www.ncdc.noaa.gov/paleo/study/24030","originalSource":null,"publication":[{"abstract":"The amplitude of climatic change, as recorded in the benthic oxygen isotope record, has varied throughout geological time. During the late Pleistocene, changes in the atmospheric concentration of carbon dioxide (CO2) are an important control on this amplitude of variability. The contribution of CO2 to climate variability during the pre-Quaternary however is unknown. Here we present a new boron isotope-based CO2 record for the transition into the middle Miocene Climatic Optimum (MCO) between 15.5 and 17 Myr that shows pronounced variability between 300 ppm and 500 ppm on a roughly 100 kyr time scale during the MCO. The CO2 changes reconstructed for the Miocene are ~2 times larger in absolute terms (300 to 500 ppm compared to 180 to 280 ppm) than those associated with the late Pleistocene and ~15% larger in terms of climate forcing. In contrast, however, variability in the contemporaneous benthic oxygen isotope record (at ~1 permil) is approximately two thirds the amplitude of that seen during the late Pleistocene. These observations indicate a lower overall sensitivity to CO2 forcing for Miocene (Antarctic only) ice sheets than their late Pleistocene (Antarctic plus lower latitude northern hemisphere) counterparts. When our Miocene CO2 record is compared to the estimated changes in contemporaneous d18Osw (ice volume), they point to the existence of two reservoirs of ice on Antarctica. One of these reservoirs appears stable, while a second reservoir shows a level of dynamism that contradicts the results of coupled climate-ice sheet model experiments given the CO2 concentrations that we reconstruct.","author":{"name":"Rosanna Greenop, Gavin L. Foster, Paul A. Wilson, Caroline H. Lear"},"citation":"Rosanna Greenop, Gavin L. Foster, Paul A. Wilson, Caroline H. Lear. 2014. Middle Miocene climate instability associated with high-amplitude CO2 variability. Paleoceanography and Paleoclimatology, 29(9), 845-853. doi: 10.1002/2014PA002653","edition":null,"identifier":{"id":"10.1002/2014PA002653","type":"doi","url":"http://dx.doi.org/10.1002/2014PA002653"},"issue":"9","journal":"Paleoceanography and Paleoclimatology","pages":"845-853","pubRank":"1","pubYear":2014,"reportNumber":null,"title":"Middle Miocene climate instability associated with high-amplitude CO2 variability","type":"publication","volume":"29"}],"reconstruction":"Y","scienceKeywords":null,"site":[{"NOAASiteId":"57486","geo":{"geoType":"Feature","geometry":{"coordinates":["-16.737167","115.535"],"type":"POINT"},"properties":{"easternmostLongitude":"115.535","maxElevationMeters":"-2168","minElevationMeters":"-2168","northernmostLatitude":"-16.737167","southernmostLatitude":"-16.737167","westernmostLongitude":"115.535"}},"locationName":"Ocean>Indian Ocean","mappable":"Y","paleoData":[{"NOAADataTableId":"35793","coreLengthMeters":null,"dataFile":[{"NOAAKeywords":["earth science>paleoclimate>climate forcing>carbon dioxide"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/climate_forcing/trace_gases/Paleo-pCO2/greenop2014odp761boron.txt","linkText":"Middle Miocene ODP761 Boron Isotope and CO2 Data","urlDescription":"NOAA Template File","variables":[{"cvAdditionalInfo":null,"cvDataType":"CLIMATE FORCING|CLIMATE RECONSTRUCTIONS|PALEOCEANOGRAPHY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"million years ago","cvWhat":"age variable>age"},{"cvAdditionalInfo":"Trilobatus trilobus","cvDataType":"PALEOCEANOGRAPHY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"biological material>organism>foraminifer>planktic foraminifer","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil","cvWhat":"chemical composition>isotope>isotope ratio>delta 11B"},{"cvAdditionalInfo":"Trilobatus trilobus","cvDataType":"PALEOCEANOGRAPHY","cvDetail":null,"cvError":"two standard deviations","cvFormat":"Numeric","cvMaterial":"biological material>organism>foraminifer>planktic foraminifer","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil","cvWhat":"chemical composition>isotope>isotope ratio>delta 11B"},{"cvAdditionalInfo":"Trilobatus trilobus","cvDataType":"PALEOCEANOGRAPHY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"biological material>organism>foraminifer>planktic foraminifer","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"millimole per mole","cvWhat":"chemical composition>element or compound ratio>magnesium/calcium"},{"cvAdditionalInfo":"based on planktic foram delta 11B","cvDataType":"CLIMATE FORCING|PALEOCEANOGRAPHY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"atmospheric material>bulk atmosphere","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"parts per million","cvWhat":"chemical composition>compound>inorganic compound>carbon dioxide"},{"cvAdditionalInfo":"based on planktic foram delta 11B","cvDataType":"CLIMATE FORCING|PALEOCEANOGRAPHY","cvDetail":null,"cvError":"two standard deviations upper bound","cvFormat":"Numeric","cvMaterial":"atmospheric material>bulk atmosphere","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"parts per million","cvWhat":"chemical composition>compound>inorganic compound>carbon dioxide"},{"cvAdditionalInfo":"based on planktic foram delta 11B","cvDataType":"CLIMATE FORCING|PALEOCEANOGRAPHY","cvDetail":null,"cvError":"two standard deviations lower bound","cvFormat":"Numeric","cvMaterial":"atmospheric material>bulk atmosphere","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"parts per million","cvWhat":"chemical composition>compound>inorganic compound>carbon dioxide"}]},{"NOAAKeywords":["earth science>paleoclimate>climate forcing>carbon dioxide"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/climate_forcing/trace_gases/Paleo-pCO2/greenop2014odp761boron.xlsx","linkText":"Middle Miocene ODP761 Boron Isotope and CO2 Data","urlDescription":"Excel File","variables":[]}],"dataTableName":"Grenop2014ODP761boron","dataTableNotes":null,"earliestYear":17110000,"earliestYearBP":17110000,"earliestYearCE":-17108050,"mostRecentYear":15540000,"mostRecentYearBP":15540000,"mostRecentYearCE":-15538050,"species":[],"timeUnit":"cal yr BP"}],"siteName":"ODP 761C"}],"studyCode":null,"studyName":"Paleo-pCO2 Database Middle Miocene ODP761 Boron Isotope and CO2 Data","studyNotes":"Paleo-CO2 derived from boron isotope measurements on marine sediment core ODP761B for the middle Miocene (~17 - 15 million years ago), contributed to the Paleo-pCO2 Database","version":"1.0","xmlId":"22174"}