North Atlantic Holocene Sortable Silt Grain Size Data Hoogakker, B.A.A.; Chapman, M.R.; McCave, I.N.; Hillaire-Marcel, C.; Ellison, C.R.W; Hall, I.R.; Telford, R.J. Hoogakker, B.A.A. Chapman, M.R. McCave, I.N. Hillaire-Marcel, C. Ellison, C.R.W Hall, I.R. Telford, R.J. Meridional Overturning Circulation (MOC) earth science/paleoclimate/paleoceanography (grain size mean,null,null,micrometer,null,paleoceanography,null,null,N,carbonate and opal free; 10-63 mcm fraction) earth science/paleoclimate/paleoceanography (delta 18O,Cibicidoides wuellerstorfi,null,per mil,null,paleoceanography,null,null,N,null) earth science/paleoclimate/paleoceanography (delta 13C,Cibicidoides wuellerstorfi,null,per mil,null,paleoceanography,null,null,N,null) earth science/paleoclimate/paleoceanography (depth,null,null,centimeter,null,paleoceanography,composited,null,N,null) earth science/paleoclimate/paleoceanography (delta 18O,Cibicidoides wuellerstorfi,null,per mil,null,paleoceanography,corrected,null,N,plus 0.64) earth science/paleoclimate/paleoceanography (age,null,null,calendar year before present,null,paleoceanography,null,null,N,null) earth science/paleoclimate/paleoceanography (depth at sample start,null,null,centimeter,null,paleoceanography,null,null,N,null) earth science/paleoclimate/paleoceanography (depth at sample end,null,null,centimeter,null,paleoceanography,null,null,N,null) earth science/paleoclimate/paleoceanography (depth,null,null,centimeter,null,paleoceanography,null,null,N,null) earth science/paleoclimate/paleocean earth science/paleoclimate/paleocean (MD95-2024>LATITUDE 50.208>LONGITUDE -45.688) (ODP 980>LATITUDE 55.48>LONGITUDE -14.7) (MD99-2251>LATITUDE 57.458>LONGITUDE -27.913) High resolution flow speed reconstructions of two core sites located on Gardar Drift in the northeast Atlantic Basin and Orphan Knoll in the northwest Atlantic Basin reveal a long-term decrease in flow speed of Northeast Atlantic Deep Water (NEADW) after 6,500 years. Benthic foraminiferal oxygen isotopes of sites currently bathed in NEADW show a 0.2‰ depletion after 6,500 years, shortly after the start of the development of a carbon isotope gradient between NEADW and Norwegian Sea Deep Water. We consider these changes in near-bottom flow vigor and benthic foraminiferal isotope records to mark a significant reorganization of the Holocene deep ocean circulation, and attribute the changes to a weakening of NEADW flow during the mid to late Holocene that allowed the shoaling of Lower Deep Water and deeper eastward advection of Labrador Sea Water into the northeast Atlantic Basin. STUDY NOTES: Sortable silt grain sizes data for box core HU91 045 093 HR and piston core MD95 2024 from Orphan Knoll in the Labrador Sea, and piston core MD99 2251 from Gardar Drift. At both sites sortable silt grain sizes were measured (mean grain size of the carbonate and opal free 10-63 um fraction), and for the site in the Labrador Sea benthic foraminiferal oxygen isotopes (epifaunal Cibicidoides wuellerstorfi) were also measured. NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Hoogakker, B.A.A. Investigator : Chapman, M.R. Investigator : McCave, I.N. Investigator : Hillaire-Marcel, C. Investigator : Ellison, C.R.W Investigator : Hall, I.R. Investigator : Telford, R.J. 2011-11-22 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/12277 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/hoogakker2011/hoogakker2011.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/hoogakker2011/hoogakker2011.xls https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/hoogakker2011/hoogakker2011.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/hoogakker2011/hoogakker2011.xls English https://www.ncdc.noaa.gov/paleo/study/12277 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/hoogakker2011/hoogakker2011.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/hoogakker2011/hoogakker2011.xls Hoogakker, B.A.A., M.R. Chapman, I.N. McCave, C. Hillaire-Marcel, C.R.W. Ellison, I.R. Hall, and R.J. Telford. 2011. Dynamics of North Atlantic Deep Water masses during the Holocene. Paleoceanography, Vol. 26, PA4214, doi:10.1029/2011PA002155. START YEAR: 10116 cal yr BP * END YEAR: 16 cal yr BP -45.688 50.208 -14.7 57.458