{"NOAAStudyId":"2617","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":"2002-07-01","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-2617.xml","doi":null,"earliestYearBP":63578,"earliestYearCE":-61628,"entryId":"noaa-ocean-2617","funding":[],"investigators":"Altabet, M.A.; Higginson, M.J.; Murray, D.W.","mostRecentYearBP":0,"mostRecentYearCE":1950,"onlineResourceLink":"https://www.ncdc.noaa.gov/paleo/study/2617","originalSource":null,"publication":[{"abstract":"Most global biogeochemical processes are known to respond to climate change, some of which have the capacity to produce feedbacks through the regulation of atmospheric greenhouse gases. Marine denitrification-the reduction of nitrate to gaseous nitrogen-is an important process in this regard, affecting greenhouse gas concentrations directly through the incidental production of nitrous oxide, and indirectly through modification of the marine nitrogen inventory and hence the biological pump for CO2. Although denitrification has been shown to vary with glacial-interglacial cycles, its response to more rapid climate change has not yet been well characterized. Here we present nitrogen isotope ratio, nitrogen content and chlorin abundance data from sediment cores with high accumulation rates on the Oman continental margin that reveal substantial millennial-scale variability in Arabian Sea denitrification and productivity during the last glacial period. The detailed correspondence of these changes with Dansgaard-Oeschger events recorded in Greenland ice cores indicates rapid, century-scale reorganization of the Arabian Sea ecosystem in response to climate excursions, mediated through the intensity of summer monsoonal upwelling. Considering the several-thousand-year residence time of fixed nitrogen in the ocean, the response of global marine productivity to changes in denitrification would have occurred at lower frequency and appears to be related to climatic and atmospheric CO2 oscillations observed in Antarctic ice cores between 20 and 60 kyr ago.","author":null,"citation":"Altabet, M.A., M.J. Higginson, and D.W. Murray. 2002. The effect of millennial-scale changes in Arabian Sea denitrification on atmospheric CO2. Nature 415:159-162.","edition":null,"identifier":null,"issue":null,"journal":"Nature","pages":null,"pubRank":"1","pubYear":2002,"reportNumber":null,"title":"The effect of millennial-scale changes in Arabian Sea denitrification on atmospheric CO2","type":"publication","volume":null}],"reconstruction":"N","scienceKeywords":null,"site":[{"NOAASiteId":"19246","geo":{"geoType":"Feature","geometry":{"coordinates":["18.25","57.65"],"type":"POINT"},"properties":{"easternmostLongitude":"57.65","maxElevationMeters":"-596","minElevationMeters":"-596","northernmostLatitude":"18.25","southernmostLatitude":"18.25","westernmostLongitude":"57.65"}},"locationName":"Ocean>Indian Ocean","mappable":"Y","paleoData":[{"NOAADataTableId":"4305","coreLengthMeters":null,"dataFile":[{"NOAAKeywords":["earth science>paleoclimate>paleocean>nitrogen isotopes","earth science>paleoclimate>paleocean>age 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Ocean","mappable":"Y","paleoData":[{"NOAADataTableId":"4306","coreLengthMeters":null,"dataFile":[{"NOAAKeywords":["earth science>paleoclimate>paleocean>age control","earth science>paleoclimate>paleocean>biomarkers","earth science>paleoclimate>paleocean>geochemistry","earth science>paleoclimate>paleocean>nitrogen isotopes"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/altabet2002","linkText":"altabet2002","urlDescription":"Original Data and Full Metadata","variables":[]},{"NOAAKeywords":["earth science>paleoclimate>paleocean>age control","earth science>paleoclimate>paleocean>biomarkers","earth science>paleoclimate>paleocean>geochemistry","earth science>paleoclimate>paleocean>nitrogen isotopes"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/paleocean/sediment_files/complete/rc27-23-tab.txt","linkText":"rc27-23-tab.txt","urlDescription":"Alternate Format Data","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":"radiocarbon year before present","cvWhat":"age variable>age"},{"cvAdditionalInfo":null,"cvDataType":"PALEOCEANOGRAPHY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"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":"percent","cvWhat":"chemical composition>element or single-element molecule>nitrogen"},{"cvAdditionalInfo":null,"cvDataType":"PALEOCEANOGRAPHY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"geological material>bulk geological material>sediment","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"microgram per gram","cvWhat":"chemical composition>compound>organic compound>aromatic compound>chlorin"}]}],"dataTableName":"RC27-23","dataTableNotes":"Substantial millennial-scale variability in Arabian Sea denitrification and productivity is indicated during the last glacial period.","earliestYear":63578,"earliestYearBP":63578,"earliestYearCE":-61628,"mostRecentYear":130,"mostRecentYearBP":0,"mostRecentYearCE":1950,"species":[],"timeUnit":"14C yr BP"}],"siteName":"RC27-23"}],"studyCode":null,"studyName":"Arabian Sea Denitrification Data ","studyNotes":null,"version":"1.0","xmlId":"1688"}