noaa-ocean-16556 Northwest Atlantic Sediment Data Across the Marine Isotope Stage 5a/4 Boundary Thornalley, D.J.R.; Barker, S.; Becker, J.; Hall, I.R.; Knorr, G. Northwest Atlantic Sediment Data Across the Marine Isotope Stage 5a/4 Boundary 2014-06-05 NCDC-Paleoclimatology ONLINE Files Pending https://www.ncdc.noaa.gov/paleo/study/16556 Investigator D.J.R. Thornalley Investigator S. Barker Investigator J. Becker Investigator I.R. Hall Investigator G. Knorr earth science paleoclimate paleoceanography depth,null,null,meter,null,paleoceanography,composited,null,N,null earth science paleoclimate paleoceanography sortable silt mean grain size,null,null,micrometer,null,paleoceanography,smoothed,null,N,3-point smooth earth science paleoclimate paleoceanography sortable silt mean grain size,null,one standard error,micrometer,null,paleoceanography,normalized,null,N,D-O interstadial 19 normalized to long-term mean earth science paleoclimate paleoceanography sortable silt mean grain size,null,null,micrometer,null,paleoceanography,normalized,null,N,early MIS4 normalized to long-term mean earth science paleoclimate paleoceanography age,null,null,calendar kiloyear before present,null,paleoceanography,null,null,N,null earth science paleoclimate paleoceanography depth,null,null,meter,null,paleoceanography,null,null,N,null earth science paleoclimate paleoceanography sortable silt mean grain size,null,null,micrometer,null,paleoceanography,normalized,null,N,D-O stadial 20 (CO 20) normalized to long-term mean earth science paleoclimate paleoceanography delta 13C,Cibicidoides sp.,null,per mil VPDB,null,paleoceanography,null,null,N,null earth science paleoclimate paleoceanography sortable silt mean grain size,null,one standard error,micrometer,null,paleoceanography,normalized,null,N,D-O interstadial 20 normalized to long-term mean earth science paleoclimate paleoceanography sortable silt mean grain size,null,one standard error,micrometer,null,paleoceanography,normalized,null,N,D-O stadial 19 (CO 19) normalized to long-term mean earth science paleoclimate paleoceanography sortable silt mean grain size,null,one standard error,micrometer,null,paleoceanography,normalized,null,N,Heinrich stadial 6 normalized to long-term mean earth science paleoclimate paleoceanography delta 13C,Cibicidoides wuellerstorfi,null,per mil VPDB,null,paleoceanography,resampled,null,N,500yr bins earth science paleoclimate paleoceanography delta 13C,Cibicidoides sp.,null,per mil VPDB,null,paleoceanography,smoothed,null,N,3-point smooth earth science paleoclimate paleoceanography sortable silt mean grain size,null,null,micrometer,null,paleoceanography,normalized,null,N,D-O stadial 19 (CO 19) normalized to long-term mean earth science paleoclimate paleoceanography sortable silt mean grain size,null,null,micrometer,null,paleoceanography,normalized,null,N,Last Glacial Maximum normalized to long-term mean earth science paleoclimate paleoceanography sortable silt mean grain size,null,one standard error,micrometer,null,paleoceanography,normalized,null,N,Last Glacial Maximum normalized to long-term mean earth science paleoclimate paleoceanography sortable silt mean grain size,null,null,micrometer,null,paleoceanography,normalized,null,N,normalized to site long-term mean earth science paleoclimate paleoceanography sortable silt mean grain size,null,null,micrometer,null,paleoceanography,normalized,null,N,D-O interstadial 21 normalized to long-term mean earth science paleoclimate paleoceanography sortable silt mean grain size,null,one standard error,micrometer,null,paleoceanography,normalized,null,N,D-O interstadial 21 normalized to long-term mean earth science paleoclimate paleoceanography sortable silt mean grain size,null,null,micrometer,null,paleoceanography,normalized,null,N,D-O interstadial 19 normalized to long-term mean earth science paleoclimate paleoceanography sortable silt mean grain size,null,one standard error,micrometer,null,paleoceanography,normalized,null,N,early MIS4 normalized to long-term mean earth science paleoclimate paleoceanography delta 18O,Globigerinoides ruber,null,per mil VPDB,null,paleoceanography,null,null,N,null earth science paleoclimate paleoceanography delta 18O,Globigerinoides ruber,null,per mil VPDB,null,paleoceanography,smoothed,null,N,3-point smooth earth science paleoclimate paleoceanography delta 18O,benthic foraminifer,null,per mil VPDB,null,paleoceanography,null,null,N,Cibicidoides lobatulus and Cibicidoides wuellerstorfi earth science paleoclimate paleoceanography delta 18O,benthic foraminifer,null,per mil VPDB,null,paleoceanography,smoothed,null,N,Cibicidoides lobatulus and Cibicidoides wuellerstorfi; 3-point smooth earth science paleoclimate paleoceanography foraminifer fragmentation,null,null,percent,null,paleoceanography,null,null,N,planktic fragmentation earth science paleoclimate paleoceanography foraminifer fragmentation,null,null,percent,null,paleoceanography,smoothed,null,N,3-point smooth earth science paleoclimate paleoceanography sand,sediment,null,percent,null,paleoceanography,null,null,N,>63µm earth science paleoclimate paleoceanography delta 18O,Cibicidoides wuellerstorfi,null,per mil VPDB,null,paleoceanography,null,null,N,null earth science paleoclimate paleoceanography delta 13C,Cibicidoides wuellerstorfi,null,per mil VPDB,null,paleoceanography,null,null,N,null earth science paleoclimate paleoceanography sortable silt mean grain size,null,null,micrometer,null,paleoceanography,normalized,null,N,Heinrich stadial 6 normalized to long-term mean earth science paleoclimate paleoceanography sortable silt mean grain size,null,null,micrometer,null,paleoceanography,null,null,N,null earth science paleoclimate paleoceanography delta 18O,Cibicidoides sp.,null,per mil VPDB,null,paleoceanography,null,null,N,null earth science paleoclimate paleoceanography sortable silt mean grain size,null,one standard error,micrometer,null,paleoceanography,normalized,null,N,D-O stadial 20 (CO 20) normalized to long-term mean earth science paleoclimate paleoceanography sortable silt mean grain size,null,null,micrometer,null,paleoceanography,normalized,null,N,D-O interstadial 20 normalized to long-term mean; silt fraction earth science paleoclimate paleoceanography sortable silt mean grain size,null,one standard error,micrometer,null,paleoceanography,normalized,null,N,Holocene normalized to long-term mean earth science paleoclimate paleocean oxygen isotopes earth science paleoclimate paleocean carbon isotopes earth science paleoclimate paleocean physical properties geoscientificInformation Dansgaard-Oeschger cycles Heinrich Events 85908 cal yr BP 55600 cal yr BP Complete 29.933333 33.683333 -76.283333 -57.616667 -4584 -1798 Ocean Atlantic Ocean North Atlantic Ocean ODP1060>LATITUDE 30.766667>LONGITUDE -74.466667 Ocean Atlantic Ocean North Atlantic Ocean ODP 1055>LATITUDE 32.783333>LONGITUDE -76.283333 Ocean Atlantic Ocean North Atlantic Ocean ODP 1057>LATITUDE 32.033333>LONGITUDE -76.05 Ocean Atlantic Ocean North Atlantic Ocean Western North Atlantic Ocean>LATITUDE >LONGITUDE Ocean Atlantic Ocean North Atlantic Ocean ODP 1059>LATITUDE 31.683333>LONGITUDE -75.416667 Ocean Atlantic Ocean North Atlantic Ocean ODP1061>LATITUDE 29.933333>LONGITUDE -73.6 Ocean Atlantic Ocean North Atlantic Ocean ODP1063>LATITUDE 33.683333>LONGITUDE -57.616667 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 Thornalley, D.J.R., S. Barker, J. Becker, I.R. Hall, and G. Knorr 2013 Paleoceanography 28 253-262 10.1002/palo.20025

Six Ocean Drilling Program (ODP) sites, in the Northwest Atlantic have been used to investigate kinematic and chemical changes in the "Western Boundary Undercurrent" (WBUC) during the development of full glacial conditions across the Marine Isotope Stage 5a/4 boundary (~70,000?years ago). Sortable silt mean grain size inline image measurements are employed to examine changes in near bottom flow speeds, together with carbon isotopes measured in benthic foraminifera and % planktic foraminiferal fragmentation as proxies for changes in water-mass chemistry. A depth transect of cores, spanning 1.8–4.6?km depth, allows changes in both the strength and depth of the WBUC to be constrained across millennial scale events. inline image measurements reveal that the flow speed structure of the WBUC during warm intervals (“interstadials”) was comparable to modern (Holocene) conditions. However, significant differences are observed during cold intervals, with higher relative flow speeds inferred for the shallow component of the WBUC (~2?km depth) during all cold “stadial” intervals (including Heinrich Stadial 6), and a substantial weakening of the deep component (~3-4 km) during full glacial conditions. Our results therefore reveal that the onset of full glacial conditions was associated with a regime shift to a shallower mode of circulation (involving Glacial North Atlantic Intermediate Water) that was quantitatively distinct from preceding cold stadial events. Furthermore, our chemical proxy data show that the physical response of the WBUC during the last glacial inception was probably coupled to basin-wide changes in the water-mass composition of the deep Northwest Atlantic.

GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/thornalley2013/thornalley2013-ss-normholo.txt Formatted Text File; Normalized SS depth transect relative to Holocene GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/thornalley2013/thornalley2013-odp1059-jpc37.txt Formatted Text File; ODP1059/KNR140-2-JPC37 C. wuellerstorfi d13C Data GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/thornalley2013/thornalley2013-odp1063.txt Formatted Text File; ODP1063 Sortable Silt and Isotope Data GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/thornalley2013/thornalley2013-odp1059-benth.txt Formatted Text File; ODP1059 C. wuellerstorfi d18O Data GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/thornalley2013/thornalley2013-ss-norm.txt Formatted Text File; Normalized SS depth transect GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/thornalley2013/thornalley2013-odp1055.txt Formatted Text File; ODP1055 Sortable Silt and Isotope Data GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/thornalley2013/thornalley2013-odp1061.txt Formatted Text File; ODP1061 Sortable Silt Data GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/thornalley2013/thornalley2013-odp1057.txt Formatted Text File; ODP1057 Sortable Silt Data GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/thornalley2013/thornalley2013-odp1059.txt Formatted Text File; ODP1059 Sortable Silt and Isotope Data GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/thornalley2013/thornalley2013-odp1060.txt Formatted Text File; ODP1060 Sortable Silt Data USA/NOAA DIF Version 9.8.4 2018-12-11 2018-12-11