{"NOAAStudyId":"15068","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":"2013-09-18","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-15068.xml","doi":null,"earliestYearBP":157450,"earliestYearCE":-155500,"entryId":"noaa-ocean-15068","funding":[{"fundingAgency":"Swiss National Science Foundation","fundingGrant":"200021-131886/1"},{"fundingAgency":"National Science Foundation","fundingGrant":"OCE-1060947"},{"fundingAgency":"Grand Challenges Program of Princeton University","fundingGrant":null}],"investigators":"Straub, M.; Sigman, D.M.; Ren, H.; Martínez-Garcia, A.; Meckler, A.N.; Hain, M.P.; Haug, G.H.","mostRecentYearBP":4020,"mostRecentYearCE":-2070,"onlineResourceLink":"https://www.ncdc.noaa.gov/paleo/study/15068","originalSource":null,"publication":[{"abstract":"In the ocean, the chemical forms of nitrogen that are readily available for biological use (known collectively as ‘fixed’ nitrogen) fuel the global phytoplankton productivity that exports carbon to the deep ocean. Accordingly, variation in the oceanic fixed nitrogen reservoir has been proposed as a cause of glacial–interglacial changes in atmospheric carbon dioxide concentration. Marine nitrogen fixation, which produces most of the ocean’s fixed nitrogen, is thought to be affected by multiple factors, including ocean temperature and the availability of iron and phosphorus. Here we reconstruct changes in North Atlantic nitrogen fixation over the past 160,000 years from the shell-bound nitrogen isotope ratio (15N/14N) of planktonic foraminifera in Caribbean Sea sediments. The observed changes cannot be explained by reconstructed changes in temperature, the supply of (iron-bearing) dust or water column denitrification. We identify a strong, roughly 23,000-year cycle in nitrogen fixation and suggest that it is a response to orbitally driven changes in equatorial Atlantic upwelling, which imports ‘excess’ phosphorus (phosphorus in stoichiometric excess of fixed nitrogen) into the tropical North Atlantic surface. In addition, we find that nitrogen fixation was reduced during glacial stages 6 and 4, when North Atlantic Deep Water had shoaled to become glacial North Atlantic intermediate water, which isolated the Atlantic thermocline from excess phosphorus-rich mid-depth waters that today enter from the Southern Ocean. Although modern studies have yielded diverse views of the controls on nitrogen fixation, our palaeobiogeochemical data suggest that excess phosphorus is the master variable in the North Atlantic Ocean and indicate that the variations in its supply over the most recent glacial cycle were dominated by the response of regional ocean circulation to the orbital cycles.","author":null,"citation":"Straub, M., D.M. Sigman, H. Ren, A. Martínez-García, A.N. Meckler, M.P. Hain and G.H. Haug. 2013. Changes in North Atlantic nitrogen fixation controlled by ocean circulation. Nature, 501, 200-203. doi:10.1038/nature12397","edition":null,"identifier":{"id":"10.1038/nature12397","type":"doi","url":"http://dx.doi.org/10.1038/nature12397"},"issue":null,"journal":"Nature","pages":null,"pubRank":"1","pubYear":2013,"reportNumber":null,"title":"Changes in North Atlantic nitrogen fixation controlled by ocean circulation","type":"publication","volume":null}],"reconstruction":"N","scienceKeywords":null,"site":[{"NOAASiteId":"19232","geo":{"geoType":"Feature","geometry":{"coordinates":["12.75","-78.73"],"type":"POINT"},"properties":{"easternmostLongitude":"-78.73","maxElevationMeters":"-2827","minElevationMeters":"-2827","northernmostLatitude":"12.75","southernmostLatitude":"12.75","westernmostLongitude":"-78.73"}},"locationName":"Ocean>Pacific Ocean>North Pacific Ocean","mappable":"Y","paleoData":[{"NOAADataTableId":"25077","coreLengthMeters":null,"dataFile":[{"NOAAKeywords":["earth science>paleoclimate>paleocean>nitrogen isotopes"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/straub2013-nat/straub2013-nature.txt","linkText":"straub2013-nature.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":null,"cvDataType":"PALEOCEANOGRAPHY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"calendar kiloyear before present","cvWhat":"age variable>age"},{"cvAdditionalInfo":null,"cvDataType":"PALEOCEANOGRAPHY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"biological material>organism>foraminifer>planktic foraminifer>Globigerinoides sp.>Globigerinoides ruber","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>Trilobatus sp.>Trilobatus sacculifer","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil","cvWhat":"chemical composition>isotope>isotope ratio>delta 15N"},{"cvAdditionalInfo":null,"cvDataType":"PALEOCEANOGRAPHY","cvDetail":"averaged","cvError":null,"cvFormat":"Numeric","cvMaterial":"biological material>organism>foraminifer>planktic foraminifer>Globigerinoides sp.>Globigerinoides ruber","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil","cvWhat":"chemical composition>isotope>isotope ratio>delta 15N"},{"cvAdditionalInfo":null,"cvDataType":"PALEOCEANOGRAPHY","cvDetail":"averaged","cvError":null,"cvFormat":"Numeric","cvMaterial":"biological material>organism>foraminifer>planktic foraminifer>Trilobatus sp.>Trilobatus sacculifer","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil","cvWhat":"chemical composition>isotope>isotope ratio>delta 15N"}]}],"dataTableName":"ODP999A Straub13-Nature","dataTableNotes":"Age based on alignment to LR04 benthic stack (Liesicki and Raymo 2005) and age model (C-14 datings) of Schmidt et al. 2006. Depth is middle depth of sample taken.","earliestYear":157450,"earliestYearBP":157450,"earliestYearCE":-155500,"mostRecentYear":4020,"mostRecentYearBP":4020,"mostRecentYearCE":-2070,"species":[],"timeUnit":"cal yr BP"}],"siteName":"ODP 999A"}],"studyCode":null,"studyName":"Caribbean Sea Nitrogen Isotope Data From ODP999 Over the Last 160,000 Years","studyNotes":null,"version":"1.0","xmlId":"12910"}