{"NOAAStudyId":"12195","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":"2011-09-26","dataPublisher":"NOAA","dataType":"CLIMATE RECONSTRUCTIONS","dataTypeInformation":"https://www.ncdc.noaa.gov/data-access/paleoclimatology-data/datasets/climate-reconstruction","difMetadataLink":"http://www1.ncdc.noaa.gov/pub/data/metadata/published/paleo/dif/xml/noaa-recon-12195.xml","doi":null,"earliestYearBP":29760,"earliestYearCE":-27810,"entryId":"noaa-recon-12195","funding":[{"fundingAgency":"Natural Sciences and Engineering Research Council of Canada","fundingGrant":null},{"fundingAgency":"US National Science Foundation","fundingGrant":null},{"fundingAgency":"Canadian Institute for Advanced Research (CIFAR)","fundingGrant":null}],"investigators":"Dubois, N.; Kienast, M.; Normandeau, C.; Herbert, T.D.","mostRecentYearBP":980,"mostRecentYearCE":970,"onlineResourceLink":"https://www.ncdc.noaa.gov/paleo/study/12195","originalSource":null,"publication":[{"abstract":"We present new alkenone-based sea surface temperature (SST) \r\nestimates from the eastern equatorial Pacific (EEP) for the \r\nlast 30 kyr. By combining these new results with recently \r\npublished records from the region, we reconstruct the spatial \r\npattern of changes in SST during the Last Glacial Maximum (LGM). \r\nAlkenone-based SST estimates show a greater glacial cooling \r\nin the upwelling environment of the cold tongue than in sites \r\nlocated further north in the equatorial front and eastern Pacific \r\nWarm Pool. This result agrees with the paradigm of stronger \r\nglacial winds, increased upwelling, steeper zonal thermocline \r\ntilt, and stronger advection of cold water in the Peru Current. \r\nFurthermore, we investigate possible changes in glacial surface \r\nhydrography by using the alkenone-based SST reconstructions \r\nto correct planktonic foraminifera d18O for the temperature effect. \r\nAfter additional correction for the global ice volume effect, \r\nthe residual changes in seawater d18O show a clear latitudinal \r\npattern that would be consistent with a southward shift of the \r\nIntertropical Convergence Zone. We thus suggest that changes \r\nin sea surface salinities could explain contrasting SST \r\nreconstructions based on planktonic foraminifera d18O, \r\nwhich implied a weakening of the cold tongue. The controversial \r\nLGM dynamics of the EEP reconstructed by different proxies, \r\ni.e., a weakening or a strengthening of the cold tongue, \r\nhighlight the necessity to better assess the influence \r\nof various biases on these proxies. \r\n\r\n\r\n","author":null,"citation":"Dubois, N., M. Kienast, C. Normandeau, and T.D. Herbert. 2009. \r\nEastern equatorial Pacific cold tongue during the Last Glacial \r\nMaximum as seen from alkenone paleothermometry. \r\nPaleoceanography, 24, PA4207, doi:10.1029/2009PA001781. \r\n","edition":null,"identifier":{"id":"10.1029/2009PA001781","type":"doi","url":"http://dx.doi.org/10.1029/2009PA001781"},"issue":null,"journal":"Paleoceanography","pages":null,"pubRank":"1","pubYear":2009,"reportNumber":null,"title":"Eastern equatorial Pacific cold tongue during the Last Glacial  Maximum as seen from alkenone paleothermometry","type":"publication","volume":null}],"reconstruction":"Y","scienceKeywords":["Sea Surface Temperature Reconstruction","Last Glacial Maximum"],"site":[{"NOAASiteId":"19114","geo":{"geoType":"Feature","geometry":{"coordinates":["-3.62","-83.97"],"type":"POINT"},"properties":{"easternmostLongitude":"-83.97","maxElevationMeters":"-3210","minElevationMeters":"-3210","northernmostLatitude":"-3.62","southernmostLatitude":"-3.62","westernmostLongitude":"-83.97"}},"locationName":"Ocean>Pacific Ocean>Eastern Pacific Ocean","mappable":"Y","paleoData":[{"NOAADataTableId":"20504","coreLengthMeters":2,"dataFile":[{"NOAAKeywords":["earth science>paleoclimate>reconstructions>sea surface temperature"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/dubois2009/dubois2009.txt","linkText":"dubois2009.txt","urlDescription":"Original Data and Full Metadata","variables":[{"cvAdditionalInfo":null,"cvDataType":"CLIMATE 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BP"}],"siteName":"ME0005A-27JC"},{"NOAASiteId":"52403","geo":{"geoType":"Feature","geometry":{"coordinates":["7.85583","-83.60833"],"type":"POINT"},"properties":{"easternmostLongitude":"-83.60833","maxElevationMeters":"-1368","minElevationMeters":"-1368","northernmostLatitude":"7.85583","southernmostLatitude":"7.85583","westernmostLongitude":"-83.60833"}},"locationName":"Ocean>Pacific Ocean>Eastern Pacific Ocean","mappable":"Y","paleoData":[{"NOAADataTableId":"20501","coreLengthMeters":null,"dataFile":[{"NOAAKeywords":["earth science>paleoclimate>reconstructions>sea surface temperature"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/dubois2009/dubois2009.txt","linkText":"dubois2009.txt","urlDescription":"Original Data and Full Metadata","variables":[{"cvAdditionalInfo":null,"cvDataType":"CLIMATE 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BP"}],"siteName":"ME0005A-43JC"},{"NOAASiteId":"52404","geo":{"geoType":"Feature","geometry":{"coordinates":[".515","-92.3983"],"type":"POINT"},"properties":{"easternmostLongitude":"-92.3983","maxElevationMeters":"-2830","minElevationMeters":"-2830","northernmostLatitude":"0.515","southernmostLatitude":"0.515","westernmostLongitude":"-92.3983"}},"locationName":"Ocean>Pacific Ocean>Eastern Pacific Ocean","mappable":"Y","paleoData":[{"NOAADataTableId":"20503","coreLengthMeters":null,"dataFile":[{"NOAAKeywords":["earth science>paleoclimate>reconstructions>sea surface temperature"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/dubois2009/dubois2009.txt","linkText":"dubois2009.txt","urlDescription":"Original Data and Full Metadata","variables":[{"cvAdditionalInfo":null,"cvDataType":"CLIMATE 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Reconstructions","studyNotes":"Reconstructed alkenone-based sea surface temperature from five \neastern equatorial Pacific sediment cores covering the last 30 kyr BP.\n\nCores ME0005A-27JC, ME0005A-43JC and TR163-31P were analyzed for \nalkenone unsaturation at Dalhousie University following standard \nlaboratory procedures detailed by Kienast et al. (2006), whereas \ncores TR163-19P and TR163-22P where analyzed at Brown University \nfollowing similar laboratory procedures detailed by Herbert et al. \n(1998). \n\nThe age models for these cores were adopted as published in earlier \nstudies (ME0005A-27JC from Kienast et al. 2007, ME0005A-43JC from \nBenway et al. 2006, TR163-19P from Lea et al. 2000, TR163-22P from \nLea et al. 2006, TR163-31P from Martin et al. 2002). \n\nThe alkenone unsaturation index UK037 is calculated as \nUK'37 = (C37:2)/(C37:3 + C37:2), where (C37:2) and (C37:3) are \nconcentrations of the diunsaturated and triunsaturated C37 methyl \nalkenones. For conversion into temperature estimates, we used the \nculture calibration of Prahl et al. (1988) (UK'37 = 0.034T + 0.039). \nReplicate analyses of selected samples indicate an analytical \nprecision of about ±0.01 UK'37 units (0.3°C). \n","version":"1.0","xmlId":"10258"}