{"NOAAStudyId":"15069","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":"2013-09-16","dataPublisher":"NOAA","dataType":"PALEOCEANOGRAPHY","dataTypeInformation":"https://www.ncdc.noaa.gov/data-access/paleoclimatology-data/datasets/paleoceanography","difMetadataLink":"http://www1.ncdc.noaa.gov/pub/data/metadata/published/paleo/dif/xml/noaa-ocean-15069.xml","doi":null,"earliestYearBP":null,"earliestYearCE":null,"entryId":"noaa-ocean-15069","funding":[{"fundingAgency":"Swiss National Science Foundation","fundingGrant":"200021-131886/1"},{"fundingAgency":"National Science Foundation","fundingGrant":"OCE-1060947"},{"fundingAgency":"NOAA Ernest F. Hollings Scholarship Program","fundingGrant":null}],"investigators":"Straub, M.; Tremblay, M.M.; Sigman, D.M.; Studer, A.S.; Ren, H.; Toggweiler, J.R.; Haug, G.H.","mostRecentYearBP":null,"mostRecentYearCE":null,"onlineResourceLink":"https://www.ncdc.noaa.gov/paleo/study/15069","originalSource":null,"publication":[{"abstract":"Surface nitrate concentration is a potentially useful diagnostic in reconstructing the past circulation of high-latitude North Atlantic waters. Moreover, nutrient consumption in the North Atlantic surface impacts the atmospheric concentration of carbon dioxide. To reconstruct nutrient conditions in the subpolar North Atlantic region during the last ice age, a record of foraminifera-bound d15N was measured in Neogloboquadrina pachyderma (sin.) from core V28-73 south of Iceland (57.2°N, 20.9°W). Foraminifera-bound d15N is up to 2‰ lower during the last ice age than during the Holocene, suggesting as much as ~25% less complete nitrate consumption during the former. This is consistent with stronger light limitation associated with a deeper summer surface mixed layer, perhaps related to the formation of Glacial North Atlantic Intermediate Water previously suggested to have occurred near the core site. However, three single-point maxima in d15N in the glacial section and the sharp deglacial d15N rise coincide with Heinrich event layers. This suggests that increased water column stratification during Heinrich events, presumably due to surface freshening, reduced the nutrient supply from below and led to nearly complete nitrate consumption in the summertime mixed layer. The Heinrich layers in V28-73 are not accompanied by d18O minima in either N. pachyderma (sin.) or Globigerinoides bulloides, which we tentatively attribute to extreme mixed-layer shoaling. The reconstructed subpolar North Atlantic upper water column changes—both glacial/interglacial and millennial—are inverse to those inferred for the Antarctic.","author":null,"citation":"Straub, M., M.M. Tremblay, D.M. Sigman, A.S. Studer, H. Ren, J.R. Toggweiler, and G.H. Haug. 2013. Nutrient conditions in the subpolar North Atlantic during the last glacial period reconstructed from foraminifera-bound nitrogen isotopes. Paleoceanography, 28, 79-90. doi:10.1002/palo.20013","edition":null,"identifier":{"id":"10.1002/palo.20013","type":"doi","url":"http://dx.doi.org/10.1002/palo.20013"},"issue":null,"journal":"Paleoceanography","pages":null,"pubRank":"1","pubYear":2013,"reportNumber":null,"title":"Nutrient conditions in the subpolar North Atlantic during the last glacial period reconstructed from foraminifera-bound nitrogen isotopes","type":"publication","volume":null}],"reconstruction":"N","scienceKeywords":["Heinrich Events"],"site":[{"NOAASiteId":"55429","geo":{"geoType":"Feature","geometry":{"coordinates":["57.2","-20.9"],"type":"POINT"},"properties":{"easternmostLongitude":"-20.9","maxElevationMeters":"-2063","minElevationMeters":"-2063","northernmostLatitude":"57.2","southernmostLatitude":"57.2","westernmostLongitude":"-20.9"}},"locationName":"Ocean>Atlantic Ocean>North Atlantic Ocean","mappable":"Y","paleoData":[{"NOAADataTableId":"25076","coreLengthMeters":null,"dataFile":[{"NOAAKeywords":["earth science>paleoclimate>paleocean>geochemistry","earth science>paleoclimate>paleocean>oxygen isotopes","earth science>paleoclimate>paleocean>nitrogen isotopes"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/straub2013-poc/straub2013-poc.txt","linkText":"straub2013-poc.txt","urlDescription":"Original Data and Full Metadata","variables":[{"cvAdditionalInfo":null,"cvDataType":"PALEOCEANOGRAPHY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"centimeter","cvWhat":"depth variable>depth"},{"cvAdditionalInfo":"foraminiferal-bound 15N","cvDataType":"PALEOCEANOGRAPHY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"biological material>organism>foraminifer","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil","cvWhat":"chemical composition>isotope>isotope ratio>delta 15N"},{"cvAdditionalInfo":null,"cvDataType":"PALEOCEANOGRAPHY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"biological material>organism>foraminifer>planktic foraminifer>Neogloboquadrina sp.>Neogloboquadrina pachyderma>Neogloboquadrina pachyderma sinistral","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil","cvWhat":"chemical composition>isotope>isotope ratio>delta 15N"},{"cvAdditionalInfo":null,"cvDataType":"PALEOCEANOGRAPHY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"biological material>organism>foraminifer>planktic foraminifer>Globigerina sp.>Globigerina bulloides","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil","cvWhat":"chemical composition>isotope>isotope ratio>delta 15N"},{"cvAdditionalInfo":null,"cvDataType":"PALEOCEANOGRAPHY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"geological material>bulk geological material>sediment","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil","cvWhat":"chemical composition>isotope>isotope ratio>delta 15N"},{"cvAdditionalInfo":null,"cvDataType":"PALEOCEANOGRAPHY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"geological material>identified mineral>carbonate>calcium carbonate","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil VPDB","cvWhat":"chemical composition>isotope>isotope ratio>delta 18O"},{"cvAdditionalInfo":"dolomite/calcite","cvDataType":"PALEOCEANOGRAPHY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"geological material>bulk geological material>sediment","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"dimensionless","cvWhat":"geological material>identified mineral>mineral index"},{"cvAdditionalInfo":"silicate/calcite","cvDataType":"PALEOCEANOGRAPHY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"geological material>bulk geological material>sediment","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"dimensionless","cvWhat":"geological material>identified mineral>mineral index"}]}],"dataTableName":"V28-73 Straub13-POC","dataTableNotes":null,"earliestYear":null,"earliestYearBP":null,"earliestYearCE":null,"mostRecentYear":null,"mostRecentYearBP":null,"mostRecentYearCE":null,"species":[],"timeUnit":null}],"siteName":"V28-73"}],"studyCode":null,"studyName":"North Atlantic Nitrogen and Oxygen Isotope and Mineralogy Data from Last Glacial Period","studyNotes":null,"version":"1.0","xmlId":"12911"}