{"NOAAStudyId":"15088","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":"2013-09-23","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-15088.xml","doi":null,"earliestYearBP":null,"earliestYearCE":null,"entryId":"noaa-ocean-15088","funding":[{"fundingAgency":"National Science Foundation Geophysics","fundingGrant":"NSF-OCE-0961697"}],"investigators":"Stoynova, V.; Shanahan, T.M.; Hughen, K.A.; de Vernal, A.","mostRecentYearBP":null,"mostRecentYearCE":null,"onlineResourceLink":"https://www.ncdc.noaa.gov/paleo/study/15088","originalSource":null,"publication":[{"abstract":"Geological records of past sea ice, such as those contained in Arctic marine sediments, offer an opportunity to strengthen our understanding of long-term sea ice variability, provided unambiguous paleo-sea ice proxies can be developed. One such recently proposed proxy is IP25, a highly branched isoprenoid alkene biosynthesized exclusively by sea-ice dwelling diatoms (Haslea spp.), which is well preserved in marine sediments and could be used to reconstruct past changes in spring sea-ice extent. However, little is known about regional-scale controls on IP25 production in sea ice, limiting its wider applicability as a paleo-sea-ice proxy. To address this issue we examined the distributions of IP25 and the marine productivity biomarkers dinosterol and brassicasterol in a suite of surface sediment samples distributed across the Arctic. We find a statistically significant, logarithmic relationship between IP25 and spring sea ice cover in sediment samples from arctic and subarctic sites in the Pacific (n = 96, R2 = 0.67, P < 0.0001) and the Atlantic n = 25, R2 = 0.50, P < 0.0001), though the absolute concentrations of IP25 are generally higher in the Atlantic (1.6–166.4 µg/g OC) than in the Pacific (0–38.5 µg/g OC) for equivalent sea-ice cover, and there are regional and basin-specific differences in the slope of the IP25 – sea ice relationship. Using the PDIP25 index, which also includes a biomarker for marine productivity (e.g., dinosterol) the relationship with sea ice cover is improved in all of the study areas (R2 = 0.86 and R2 = 0.75 for Atlantic and Pacific, respectively) and most basin specific differences in the proxy–sea ice relationships are significantly reduced. However, there remain differences in the absolute magnitudes of the PDIP25 index for equivalent amounts of sea ice cover between the Atlantic and the Pacific, and with previously published data from Fram Strait. Nevertheless, this work demonstrates that the PDIP25 index can provide a valuable tool for sea ice reconstructions at local and regional scales.","author":null,"citation":"Stoynova, V., T.M. Shanahan, K.A. Hughen, and A. de Vernal. 2012. Insights into Circum-Arctic sea ice variability from molecular geochemistry. Quaternary Science Reviews. doi:10.1016/j.quascirev.2012.10.006.","edition":null,"identifier":{"id":"10.1016/j.quascirev.2012.10.006","type":"doi","url":"http://dx.doi.org/10.1016/j.quascirev.2012.10.006"},"issue":null,"journal":"Quaternary Science Reviews","pages":null,"pubRank":"1","pubYear":2012,"reportNumber":null,"title":"Insights into Circum-Arctic sea ice variability from molecular geochemistry","type":"publication","volume":null}],"reconstruction":"N","scienceKeywords":null,"site":[{"NOAASiteId":"55449","geo":{"geoType":"Feature","geometry":{"coordinates":["47.9055","79.3151","-179.567","179.8"],"type":"POLYGON"},"properties":{"easternmostLongitude":"179.8","maxElevationMeters":null,"minElevationMeters":null,"northernmostLatitude":"79.3151","southernmostLatitude":"47.9055","westernmostLongitude":"-179.567"}},"locationName":"Ocean>Atlantic Ocean>North Atlantic Ocean","mappable":"N","paleoData":[{"NOAADataTableId":"25115","coreLengthMeters":null,"dataFile":[{"NOAAKeywords":["earth science>paleoclimate>paleocean>geochemistry"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/stoynova2013/stoynova2013.txt","linkText":"stoynova2013.txt","urlDescription":"Original Data and Full Metadata","variables":[{"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>organic hydroxy compound>sterol>brassicasterol"},{"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>organic hydroxy compound>sterol>dinosterol"},{"cvAdditionalInfo":null,"cvDataType":"PALEOCEANOGRAPHY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"geological material>bulk geological material>sediment","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"dimensionless","cvWhat":"chemical composition>compound>organic compound>organic compound index>dinosterol ice proxy with 25 carbon atoms index"},{"cvAdditionalInfo":null,"cvDataType":"PALEOCEANOGRAPHY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"geological material>bulk geological material>sediment","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"weight percent","cvWhat":"chemical composition>element or single-element molecule>carbon>organic carbon"},{"cvAdditionalInfo":"from concentration of a monounsaturated highly branched isoprenoid alkene","cvDataType":"PALEOCEANOGRAPHY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"microgram per gram","cvWhat":"chemical composition>compound>organic compound>hydrocarbon>alkene>highly-branched isoprenoid alkene>ice proxy with 25 carbon atoms"}]}],"dataTableName":"Arctic Surface-Stoynova13","dataTableNotes":null,"earliestYear":null,"earliestYearBP":null,"earliestYearCE":null,"mostRecentYear":null,"mostRecentYearBP":null,"mostRecentYearCE":null,"species":[],"timeUnit":null}],"siteName":"Arctic Ocean"}],"studyCode":null,"studyName":"Arctic Ocean Surface Sediment Molecular Geochemistry Data","studyNotes":"The present study uses a suite of 121 archival core top surface (0-3 cm) sediment samples obtained from the Oregon State University Marine Geology Repository and the GEOTOP archives.","version":"1.0","xmlId":"12929"}