North Atlantic Core GGC5 231Pa/230Th Meridional Circulation Data ----------------------------------------------------------------------- World Data Center for Paleoclimatology, Boulder and NOAA Paleoclimatology Program ----------------------------------------------------------------------- NOTE: PLEASE CITE ORIGINAL REFERENCE WHEN USING THIS DATA!!!!! NAME OF DATA SET: North Atlantic Core GGC5 231Pa/230Th Meridional Circulation Data LAST UPDATE: 4/2008 (Original receipt by WDC Paleo) CONTRIBUTOR: Jerry McManus, Woods Hole Oceanographic Institution IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2008-039 WDC PALEO CONTRIBUTION SERIES CITATION: McManus, J.F., et al. 2008. North Atlantic Core GGC5 231Pa/230Th Meridional Circulation Data. IGBP PAGES/World Data Center for Paleoclimatology Data Contribution Series # 2008-039. NOAA/NCDC Paleoclimatology Program, Boulder CO, USA. ORIGINAL REFERENCE: McManus, J.F., R. Francois, J.-M. Gherardi, L.D. Keigwin, and S. Brown-Leger. 2004. Collapse and rapid resumption of Atlantic meridional circulation linked to deglacial climate changes. Nature, Vol. 428, pp. 834-837, 22 April 2004. ABSTRACT: The Atlantic meridional overturning circulation is widely believed to affect climate. Changes in ocean circulation have been inferred from records of the deep water chemical composition derived from sedimentary nutrient proxies, but their impact on climate is difficult to assess because such reconstructions provide insufficient constraints on the rate of overturning. Here we report measurements of 231Pa/230Th, a kinematic proxy for the meridional overturning circulation, in a sediment core from the subtropical North Atlantic Ocean. We find that the meridional overturning was nearly, or completely, eliminated during the coldest deglacial interval in the North Atlantic region, beginning with the catastrophic iceberg discharge Heinrich event H1, 17,500 yr ago, and declined sharply but briefly into the Younger Dryas cold event, about 12,700 yr ago. Following these cold events, the 231Pa/230Th record indicates that rapid accelerations of the meridional overturning circulation were concurrent with the two strongest regional warming events during deglaciation. These results confirm the significance of variations in the rate of the Atlantic meridional overturning circulation for abrupt climate changes. GEOGRAPHIC REGION: Subtropical North Atlantic Ocean PERIOD OF RECORD: 20 KYrBP - present FUNDING SOURCES: US National Science Foundation OCE and INT programmes, the France CNRS, WHOI-OCCI and Mellon awards, and the Comer Science and Education Foundation. DESCRIPTION: 231Pa/230Th data from sediments from the Bermuda rise in the deep western subtropical Atlantic, as a proxy for meridional overturning circulation. Core OCE326-GGC5: 33° 42' N, 57° 35'W, 4550 m water depth. DATA: 1. GGC5 Pa/Th Column 1: Age kyr Column 2: Pa/Th 238-based Column 3: Error Column 4: Pa/Th 232-based Column 5: Error Age Pa/Th238 Err. Pa/Th232 Err. 0.1 0.0548 0.0023 0.0543 0.0022 0.48 0.0537 0.0024 0.0538 0.0021 0.96 0.0571 0.0041 0.0572 0.0037 1.43 0.0541 0.0018 0.0535 0.0017 1.91 0.0554 0.0016 0.0549 0.0015 2.87 0.0552 0.0028 0.055 0.0025 4.78 0.0612 0.0047 0.0619 0.0049 5.73 0.0524 0.0014 0.0517 0.0013 8.46 0.05 0.0006 0.0499 0.0006 9.95 0.0574 0.0015 0.0572 0.0015 10.25 0.0607 0.0026 0.0609 0.0026 10.85 0.0621 0.0011 0.0632 0.0012 11.3 0.0643 0.0026 0.0639 0.0015 11.69 0.0673 0.0012 0.0666 0.001 11.79 0.0727 0.0045 0.0732 0.0046 11.99 0.0736 0.0036 0.0735 0.0028 12.09 0.0707 0.0017 0.0701 0.0012 12.18 0.0712 0.0013 0.0697 0.0012 12.28 0.0745 0.003 0.0746 0.0025 12.48 0.0764 0.0056 0.077 0.005 12.58 0.0794 0.0026 0.0752 0.0022 12.68 0.0706 0.0014 0.071 0.0014 12.78 0.0618 0.0021 0.062 0.0021 12.87 0.0674 0.0027 0.0674 0.0021 12.97 0.0678 0.0015 0.0667 0.0017 13.07 0.0666 0.0029 0.0661 0.0025 13.27 0.0677 0.0018 0.0676 0.0017 13.47 0.0674 0.0017 0.0665 0.0016 14.12 0.0657 0.005 0.0648 0.0045 14.38 0.0648 0.0019 0.0624 0.0017 14.51 0.0703 0.0037 0.0657 0.0029 14.59 0.0845 0.0036 0.0786 0.0032 14.66 0.0876 0.0024 0.0813 0.0019 15.09 0.0954 0.0031 0.0889 0.0025 15.56 0.0884 0.0041 0.0827 0.0034 16.03 0.0943 0.0043 0.0895 0.0038 16.48 0.0878 0.0049 0.0826 0.0041 16.79 0.0875 0.0039 0.0839 0.0035 17.16 0.0869 0.0046 0.0833 0.0041 17.21 0.0931 0.005 0.0864 0.0041 17.24 0.0906 0.0047 0.0848 0.004 17.27 0.0861 0.0048 0.0816 0.0041 17.3 0.0865 0.0039 0.0826 0.0034 17.33 0.0859 0.0037 0.0804 0.0031 17.47 0.0831 0.0046 0.0773 0.0037 17.62 0.0839 0.0089 0.0806 0.0079 17.98 0.0746 0.0096 0.072 0.0084 18.12 0.067 0.0078 0.0646 0.0066 18.19 0.0749 0.0086 0.072 0.0075 18.29 0.0633 0.0077 0.0622 0.007 18.44 0.072 0.0076 0.0654 0.0038 18.82 0.0598 0.0075 0.0585 0.0066 19.2 0.0704 0.0031 0.0665 0.0022 19.32 0.0701 0.0043 0.0665 0.0029 19.39 0.075 0.0071 0.0691 0.0043 19.43 0.0776 0.0059 0.0748 0.0051 19.47 0.0678 0.0036 0.0655 0.0027 19.54 0.0722 0.0037 0.0684 0.0026 19.62 0.07 0.004 0.0677 0.0013 Column 1: Age (kyr) Column 2: GGC5 G. inflata d18O (per mil) Age G. inflata d18O (per mil) 0.57 0.84 0.76 0.79 0.96 0.66 1.15 0.69 1.34 0.71 1.53 0.83 1.72 0.66 1.91 0.63 2.1 0.59 2.29 0.62 2.48 0.31 2.68 0.19 2.87 0.35 3.06 0.57 3.25 0.59 3.44 0.52 3.63 0.52 3.82 0.58 4.01 0.4 4.2 0.47 4.39 0.44 4.59 0.58 4.78 0.46 4.97 0.52 5.16 0.56 5.35 0.68 5.54 0.56 5.73 0.37 5.92 0.43 6.11 0.52 6.58 0.73 7.33 0.62 8.08 0.58 8.46 0.47 8.83 0.39 9.2 0.36 9.58 0.49 9.95 0.51 10.33 0.55 10.7 0.36 11.05 0.83 11.3 1.24 11.39 1.39 11.49 0.91 11.54 0.91 11.59 1.07 11.69 1.5 11.79 1.5 11.89 1.79 11.99 1.5 12.04 1.59 12.09 1.54 12.18 1.84 12.28 1.81 12.38 1.86 12.48 1.92 12.53 1.9 12.58 1.89 12.68 1.88 12.78 1.72 12.87 1.54 12.97 1.54 13.02 1.6 13.07 1.69 13.17 1.53 13.27 1.5 13.37 1.52 13.47 1.49 13.52 1.43 13.57 1.26 13.66 1.33 13.76 1.31 13.86 1.29 13.96 1.02 13.99 1.15 14.01 1.21 14.07 1.49 14.12 1.31 14.17 1.33 14.23 1.21 14.25 1.29 14.28 1.27 14.33 1.2 14.38 1.39 14.44 1.48 14.46 1.64 14.49 1.47 14.5 1.36 14.51 1.53 14.51 1.53 14.52 1.55 14.53 1.34 14.54 1.33 14.55 1.28 14.57 1.27 14.58 1.12 14.6 1.11 14.61 1.47 14.63 1.75 14.64 1.88 14.66 1.8 14.67 1.95 14.76 1.93 14.86 2.03 14.95 1.97 15.04 1.92 15.14 1.81 15.23 1.76 15.33 1.89 15.42 1.88 15.51 1.89 15.61 2.11 15.7 1.8 15.79 1.86 15.89 1.56 15.98 1.72 16.08 1.55 16.17 1.56 16.26 1.52 16.45 1.75 16.51 2.07 16.57 2.45 16.62 2.58 16.68 2.61 16.75 2.48 16.83 2.35 16.9 2.06 16.98 2.27 17.05 2.22 17.13 2.44 17.2 2.28 17.23 2.39 17.26 2.61 17.29 2.54 17.32 2.52 17.34 2.32 17.37 2.32 17.4 2.3 17.43 2.16 17.46 2.08 17.49 2.25 17.52 2.24 17.55 2.44 17.58 2.46 17.6 2.64 17.63 2.55 17.66 2.32 17.69 2.48 17.72 2.52 17.89 2.41 18.06 2.19 18.07 2.03 18.09 2.17 18.1 2.01 18.12 2 18.13 1.81 18.14 1.83 18.16 1.84 18.17 1.82 18.18 1.72 18.2 1.7 18.21 1.8 18.23 1.79 18.24 1.96 18.27 1.96 18.3 2.08 18.33 2.02 18.36 2.12 18.39 2.04 18.42 2.1 18.45 1.77 18.48 1.76 18.52 1.74 18.55 2.08 18.58 2.13 18.61 2.06 18.64 1.83 18.67 1.83 18.7 1.66 18.76 1.74 18.79 1.68 18.82 1.89 18.85 1.79 18.88 1.75 18.91 1.57 18.94 1.89 18.97 1.92 19 2.02 19.04 1.81 19.07 1.86 19.1 1.75 19.13 1.8 19.16 1.85 19.19 1.87 19.22 1.76 19.25 1.68 19.28 1.79 19.3 1.8 19.31 1.89 19.33 1.78 19.34 1.95 19.36 1.73 19.37 1.68 19.39 1.5 19.4 1.5 19.42 1.61 19.43 1.56 19.45 1.78 19.46 1.81 19.48 1.85 19.49 1.87 19.51 1.73 19.52 1.85 19.54 1.75 19.55 1.76 19.57 1.78 19.58 1.83 19.6 1.83 19.61 1.72 19.68 1.69 19.79 1.77 19.91 1.79 20.02 1.775