{"NOAAStudyId":"22850","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":"2017-10-18","dataPublisher":"NOAA","dataType":"PALEOCLIMATIC MODELING","dataTypeInformation":"https://www.ncdc.noaa.gov/data-access/paleoclimatology-data/datasets/paleoclimatology-modeling","difMetadataLink":"http://www1.ncdc.noaa.gov/pub/data/metadata/published/paleo/dif/xml/noaa-model-22850.xml","doi":null,"earliestYearBP":21000,"earliestYearCE":-19050,"entryId":"noaa-model-22850","funding":[{"fundingAgency":"Australian Research Council  ","fundingGrant":"DE150100107"}],"investigators":"Menviel, L.","mostRecentYearBP":18000,"mostRecentYearCE":-16050,"onlineResourceLink":"https://www.ncdc.noaa.gov/paleo/study/22850","originalSource":null,"publication":[{"abstract":"Atmospheric CO2 was ∼90 ppmv lower at the Last Glacial Maximum (LGM) compared to the late Holocene, but the mechanisms responsible for this change remain elusive. Here we employ a carbon isotope-enabled Earth System Model to investigate the role of ocean circulation in setting the LGM oceanic δ13C distribution, thereby improving our understanding of glacial/interglacial atmospheric CO2 variations. We find that the mean ocean δ13C change can be explained by a 378 ± 88 Gt C(2σ) smaller LGM terrestrial carbon reservoir compared to the Holocene. Critically, in this model, differences in the oceanic δ13C spatial pattern can only be reconciled with a LGM ocean circulation state characterized by a weak (10–15 Sv) and relatively shallow (2000–2500 m) North Atlantic Deep Water cell, reduced Antarctic Bottom Water transport (≤10 Sv globally integrated), and relatively weak (6–8 Sv) and shallow (1000–1500 m) North Pacific Intermediate Water formation. This oceanic circulation state is corroborated by results from the isotope-enabled Bern3D ocean model and further confirmed by high LGM ventilation ages in the deep ocean, particularly in the deep South Atlantic and South Pacific. This suggests a poorly ventilated glacial deep ocean which would have facilitated the sequestration of carbon lost from the terrestrial biosphere and atmosphere.","author":{"name":"Menviel, L., J. Yu, F. Joos, A. Mouchet, K.J. Meissner, and M.H. England"},"citation":"Menviel, L., J. Yu, F. Joos, A. Mouchet, K.J. Meissner, and M.H. England. 2017. Poorly ventilated deep ocean at the Last Glacial Maximum inferred from carbon isotopes: a data-model comparison study. Paleoceanography, 32, 2-17. doi: 10.1002/2016PA003024","edition":null,"identifier":{"id":"10.1002/2016PA003024","type":"doi","url":"http://dx.doi.org/10.1002/2016PA003024"},"issue":null,"journal":"Paleoceanography","pages":"2-17","pubRank":"1","pubYear":2017,"reportNumber":null,"title":"Poorly ventilated deep ocean at the Last Glacial Maximum inferred from carbon isotopes: a data-model comparison study","type":"publication","volume":"32"}],"reconstruction":"N","scienceKeywords":null,"site":[{"NOAASiteId":"22723","geo":{"geoType":"Feature","geometry":{"coordinates":["-90","90","-180","180"],"type":"POLYGON"},"properties":{"easternmostLongitude":"180","maxElevationMeters":null,"minElevationMeters":null,"northernmostLatitude":"90","southernmostLatitude":"-90","westernmostLongitude":"-180"}},"locationName":"Geographic Region>Global","mappable":"N","paleoData":[{"NOAADataTableId":"34013","coreLengthMeters":null,"dataFile":[{"NOAAKeywords":["earth science>paleoclimate>model>ocean model"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/gcmoutput/menviel2016/","linkText":"LOVECLIM d13C and D14C netCDF files","urlDescription":"Data Folder","variables":[{"cvAdditionalInfo":null,"cvDataType":"PALEOCLIMATIC MODELING","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"degree north","cvWhat":"sampling metadata>latitude"},{"cvAdditionalInfo":null,"cvDataType":"PALEOCLIMATIC MODELING","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"degree east","cvWhat":"sampling metadata>longitude"},{"cvAdditionalInfo":null,"cvDataType":"PALEOCLIMATIC MODELING","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"hydrologic material>sea water","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil","cvWhat":"chemical composition>isotope>isotope ratio>delta 13C"},{"cvAdditionalInfo":null,"cvDataType":"PALEOCLIMATIC MODELING","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"hydrologic material>sea water","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"dimensionless","cvWhat":"chemical composition>isotope>isotope ratio>Delta 14C"}]},{"NOAAKeywords":["earth science>paleoclimate>model>ocean model"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/gcmoutput/menviel2016/menviel2017-loveclim.txt","linkText":"Study Description and Metadata","urlDescription":"NOAA Template File","variables":[]},{"NOAAKeywords":["earth science>paleoclimate>model>ocean model"],"fileUrl":"https://doi.org/10.4225/41/58192cb8bff06","linkText":"Study Description and Link to the Data on THREDDS Server","urlDescription":"DOI Landing Page","variables":[]}],"dataTableName":"Global LOVECLIM Menviel2016","dataTableNotes":null,"earliestYear":21000,"earliestYearBP":21000,"earliestYearCE":-19050,"mostRecentYear":18000,"mostRecentYearBP":18000,"mostRecentYearCE":-16050,"species":[],"timeUnit":"cal yr BP"}],"siteName":"Global"}],"studyCode":null,"studyName":"LOVECLIM Earth System Model Last Glacial Maximum oceanic d13C and D14C data","studyNotes":"This dataset is a collection of outputs of numerical simulations performed with LOVECLIM, an Earth System Model. The\r\n model was forced with Last Glacial Maximum (~20 ka B.P.) boundary conditions (orbital parameters, ice-sheet topogra\r\nphy and albedo, CO2, d13CO2 and D14CO2).\r\nThe dataset are oceanic d13C values for 28 Last Glacial Maximum (LGM) experiments, as well as oceanic D14C values fo\r\nr a subset of the LGM experiments. d13C and D14C values are the isotopic signatures of oceanic DIC and respectively\r\nrepresent a measure of the ratio of stable isotopes  13C  and radioactive isotope 14C with respect to the standard .\r\n Both are reported in parts per thousand.\r\nLOVECLIM is an acronym made from the names of the five different models that have been coupled to built the Earth sy\r\nstem model: LOch-Vecode-Ecbilt-CLio-agIsm Model (LOVECLIM). LOVECLIM 1.2 includes representations of the atmosphere,\r\n the ocean and sea ice, the land surface (including vegetation), the ice sheets, the icebergs and the carbon cycle.\r\nThe atmospheric component is ECBilt2, a T21, 3-level quasi-geostrophic model. The oceanic component is CLIO3, which\r\nis made up of an ocean general circulation model coupled to a comprehensive thermodynamic-dynamic sea-ice model. Its\r\n horizontal resolution is 3° y 3°, and there are 20 levels in the ocean. ECBilt-CLIO is coupled to VECODE, a vegetat\r\nionmodel that simulates the dynamics of two main terrestrial plant functional types, trees and grasses, as well as d\r\nesert. VECODE also simulates the evolution of the carbon cycle over land while the oceanic carbon cycle is represent\r\ned in LOCH, a comprehensive model that takes into account both the solubility and biological pumps.\r\nLOVECLIM description is an extract from http://www.academia.edu/12279222/Description_of_the_Earth_system_model_of_in\r\ntermediate_complexity_LOVECLIM_version_1.2\r\n\r\nReference: Menviel, L., J. Yu, F. Joos, A. Mouchet, K. Meissner, M. England, \"Poorly ventilated deep ocean at the La\r\nst Glacial Maximum inferred from carbon isotopes: a data-model comparison study\", 2016, Paleoceanography,2016PA00302\r\n4, under Review.\r\n\r\n3 dimensional netcdf data of dc13 (permil, c13_X.nc) and DC14 (permil, c14_X.nc), where X denotes the name of the ex\r\nperiments described in Tables 1 and S1.\r\nPI denotes the pre-industrial control run.\r\n\r\nExperiments list  from reference paper\r\n\r\n\r\n  V1     52 ± 53GtC\r\n              NADW, AABW,  SO XP,  CT\r\nV1L            S     S     -      -142\r\nV1LNAoff      Off    I     -      -19\r\nV1LNAw         W     I     -      -22\r\nV1LNAwSOw      I     I     -      -6\r\nV1LNAwSOs      I     S     -      -75\r\nV1LNAwGR       I     I     +9%    -17\r\n\r\n  V2     205 ± 47GtC\r\n              NADW, AABW,  SO XP,  CT\r\nV2L            S    I     -       171\r\nV2LNAoff      Off   I     -       217\r\nV2LNAw         W    I     -       208\r\nV2LNAwSOw      W    W     -       212\r\nV2LNAwSOs      W    S     -       181\r\nV2LNAwSHWw     W    W     -       244\r\nV2LNAwGR       W    I     +9%     237\r\n\r\nV3       351 ± 44GtC\r\n              NADW, AABW,  SO XP,  CT\r\nV3L            S    I     -       313\r\nV3LNAoff      Off   I     -       357\r\nV3LNAw         W    I     -       346\r\nV3LNAwSOw      W    W     -       369\r\nV3LNAwSHWw     W    W     -       392\r\nV3LNAwSOwSHWw  W    W     -       426\r\nV3LSOs         S    S     -       289\r\nV3LNAwSOs      I    S     -       320\r\nV3LNAwGR       W    I     +9%     357\r\nV3LNAwGRSOs    I    S     +9%     343\r\n\r\n  V 4, 567 ± 39GtC\r\nV4LNAw         W    S     -       514\r\nV4LNAwSHWw     W    W     -       605\r\nV4LNAwSOwSHWw  W    W     -       609\r\nV4LNAwSOs      I    S     -       534\r\nV4LNAwGR       W    I     +9%     574\r\n\r\nTable 1. Main characteristics of LGM experiments. CT indicates the difference between the\r\nlate Holocene and LGM terrestrial carbon stock (GtC) for all the experiments performed and calculated following\r\nEquation 3. The mean CT and standard deviation for each set of experiments (V1-V4) is also shown.\r\nThe relative formation rates of NADW and AABW are indicated as follows: for NADW, S=Strong (>= 20 Sv),\r\nI=Intermediate (15-20 Sv), W=Weak (10-15 Sv) or Off= shutdown (2-3 Sv); for the AABW transport in the\r\nIndo-Pacific basin, S=Strong (10-16 Sv), I=Intermediate (8-10 Sv) and W=Weak (<= 7 Sv). All symbols\r\nare filled except experiments in which export production (SO XP) was enhanced by 9% over the Southern Ocean\r\n(56-36S) compared to the pre-industrial control run.\r\n\r\nContact: l.menviel@unsw.edu.au for any question on the dataset content and provenance\r\n         paola.petrelli@utas.edu.au for questions or issues with file accessibility from THREDDS server.","version":"1.0","xmlId":"21054"}