noaa-ocean-18897 Cariaco Basin, 35-55 ka Bulk Sediment and Foraminiferal Geochemistry Gibson, K.A.; Thunell, R.C.; Tappa, E.J.; Peterson, L.C.; McConnell, M. Cariaco Basin, 35-55 ka Bulk Sediment and Foraminiferal Geochemistry 2015-06-18 NCDC-Paleoclimatology ONLINE Files Pending https://www.ncdc.noaa.gov/paleo/study/18897 Investigator K.A. Gibson Investigator R.C. Thunell Investigator E.J. Tappa Investigator L.C. Peterson Investigator M. McConnell earth science paleoclimate climate reconstructions|paleoceanography sea surface temperature,magnesium/calcium,null,degree Celsius,null,climate reconstructions|paleoceanography,null,null,N,using G. ruber earth science paleoclimate paleoceanography nitrogen,sediment,null,weight percent,null,paleoceanography,null,elemental analysis,N,null earth science paleoclimate paleoceanography delta 15N,sediment,null,per mil,null,paleoceanography,null,isotope ratio mass spectrometry,N,null earth science paleoclimate paleoceanography magnesium/calcium,Globigerinoides ruber,null,millimole per mole,null,paleoceanography,null,inductively-coupled plasma mass spectrometry,N,null earth science paleoclimate paleoceanography age,null,null,calendar year before present,null,paleoceanography,null,null,N,null earth science paleoclimate paleoceanography organic carbon,sediment,null,weight percent,null,paleoceanography,null,elemental analysis,N,null earth science paleoclimate paleoceanography iron,sediment,null,weight percent,null,paleoceanography,null,energy-dispersive x-ray fluorescence spectroscopy,N,null earth science paleoclimate paleoceanography depth,null,null,centimeter,null,paleoceanography,null,null,N,null earth science paleoclimate paleoceanography molybdenum,sediment,null,weight percent,null,paleoceanography,null,energy-dispersive x-ray fluorescence spectroscopy,N,null earth science paleoclimate paleocean geochemistry earth science paleoclimate paleocean reconstruction geoscientificInformation 55004 cal yr BP 35001 cal yr BP Complete 10.67817 10.67817 -64.9715 -64.9715 -847 -847 Ocean Atlantic Ocean North Atlantic Ocean MD03-2621>LATITUDE 10.67817>LONGITUDE -64.9715 None 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. English DOC/NOAA/NESDIS/NCEI National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce https://www.ncdc.noaa.gov/data-access/paleoclimatology-data DATA Center Contact Bruce Bauer bruce.a.bauer@noaa.gov paleo@noaa.gov 303-497-6280 303-497-6513

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Boulder CO 80305-3328 USA online ASCII Kelly Ann Gibson, Robert C. Thunell, Eric J. Tappa, Larry C. Peterson, Martha McConnell 2015 Paleoceanography 30 3 253-268 10.1002/2014PA002684 http://onlinelibrary.wiley.com/doi/10.1002/2014PA002684/full

Understanding changes to the marine nitrogen cycle on millennial and shorter time scales can help determine the influence of rapid climate change on the fixed N pool and its sources and sinks. Rapid changes in denitrification have been observed in the eastern tropical North Pacific (ETNP) and Arabian Sea; however, millennial scale d15N records in regions influenced by N2 fixation are sparse. We present a sedimentary d15N record from the Cariaco Basin during marine isotope stage (MIS) 3 (~35-55 ka). The d15N record displays a pattern of millennial scale variability that tracks the Greenland ice core Dansgaard-Oeschger cycles, with higher values observed during interstadial periods, lower values during stadial periods, and abrupt transitions in between. Conditions during interstadials are similar to those at present in the Cariaco Basin, with the sedimentary d15N signal reflecting a combination of local processes and an imported regional signal. If interpreted to reflect regional processes, the interstadial d15N values (average ~5.1 per mil) support the argument that N2 fixation did not increase in the tropical North Atlantic during the last glacial. The lower d15N values during stadials, when lower sea level resulted in increased physical isolation of the basin, can be explained primarily by local processes. In spite of the importance of local processes, striking similarity is observed between the Cariaco record and millennial scale d15N records from the ETNP and Arabian Sea. The apparent synchronicity of changes observed in all three regions suggests an atmospheric teleconnection between the three sites and high-latitude climate forcing during MIS 3. STUDY NOTES: This data set contains bulk sediment (%TOC, %N, d15N, scanning XRF) and foraminferal geochemistry (Mg/Ca) used to reconstruct millennial-scale nutrient cycle dynamics in the Cariaco Basin during MIS 3.

GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/gibson2015/gibson2015mo-fe.txt Data File; Cariaco Basin MD03-2621 Mo, Fe GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/gibson2015/gibson2015d15n-toc.txt Data File; Cariaco Basin MD03-2621 d15N, %N, TOC GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/gibson2015/gibson2015mg-ca-sst.txt Data File; Cariaco Basin MD03-2621 Mg/Ca SST USA/NOAA DIF Version 9.8.4 2019-04-22 2019-04-22