Possible mechanisms include atmospheric processes that enhanced advection from the subtropics and oceanic processes that transported heat northward from the equatorial Atlantic. However, regions south of Virginia experienced little temperature change and Florida warmed slightly. New England, Maritime Canada, and the Great Lakes Region all cooled, like Greenland and elsewhere in the Northern Hemisphere. Here we present detailed reconstructions of Younger Dryas temperature variations in eastern North America that suggest a more complex spatial fingerprint than predicted by the standard global model. Its cause has been linked to a reduction in northward oceanic heat transport in the Atlantic that led to Northern Hemispheric cooling and Southern Hemispheric warming. The Younger Dryas, circa 12,900 to 11,700 years ago, is a hemispheric abrupt climate change event that occurred at rates similar to those projected by the 21st century. A conceptual model is proposed to present the key elements of depositional processes in this depositional system, and a similar evolutionary history can be expected on other distal glacial margins. In the Holocene, alongslope processes became dominant, building a drift with clearly variable thickness, in part related to seabed morphology. The two systems interacted on inter-canyon ridges, where contourite sedimentation was not completely overwhelmed by energetic turbidity currents. During the last glacial maximum and early deglaciation, turbidity currents fed either by meltwater or oceanographic processes flowed in canyons, and a contourite depositional system developed between the canyons. Depositional architecture is built through temporal and spatial coupling of the diverse sedimentary processes. Regional scale thickness variations allow discrimination between hemipelagites and muddy contourites. Glacial silty contourites have distinct rhythmic laminae with the long axis of IRD parallel to bedding. Sandy contourites are mostly massive, occurring either as lenses or as part of the ideal bi-gradational vertical sequence with mottled silt-mud. Both turbidites and contourites show stratification, but differ in internal structure, the presence of IRD, and the nature of their upper and lower boundaries. Based on the analysis of sediment cores going back to 24 ka (Heinrich event 2), this study investigates fine-grained sedimentary facies and the development of variable depositional patterns on the glacially influenced SW Grand Banks Slope off Newfoundland (eastern Canada). These include sediment transported by downslope glacial meltwater discharge, alongslope bottom currents and ice-rafting. As on other parts of the Canadian margin, its late Quaternary sediment architecture has been constructed by interacting alongslope and downslope processes. In eastern Canada, proglacial sedimentation rates are relatively high on the SW Grand Banks Slope compared to the sediment starved SE Grand Banks margin, but relatively low compared to the glacially dominated Scotian margin off eastern Canada. Maps were created using Matlab M_map function suite (created by Pawlowicz et al., ).Ĭomplex inter-relationships between alongslope and downslope sediment dispersion exist on glaciated continental margins and vary widely along continental margins depending on sediment supply and bottom current strength. Jumbo piston core (JPC) 59 is located ~15 km west of JPC25 and JPC26 and projected into line DT-c. C: Schematic profile across offbank core transect. Blue shading indicates shallow water areas (<120 m below sea level, mbsl). Bahamas hurricane reconstruction sites from Toomey et al. Location of transect (shown in inset C) is given by black line from DT to c (in inset C). Red arrow shows the generalized path of the Yucatan (YC), Loop, and Florida Currents (FC). B: Regional map of southern Florida, northern Caribbean, and Gulf of Mexico. MDR-main development region GoM-Gulf of Mexico CAT-category EQ-equator PM-prime meridian. Background color map was compiled from National Oceanic and Atmospheric Administration (NOAA) monthly satellite-derived ocean heat content data for the 2013-2015 CE storm seasons (Data Repository ). Tracks of major hurricanes that formed in the Caribbean (dark gray) versus one from the eastern North Atlantic (light gray) are noted. Location used in Figure 2 proxy reconstructions by dots: red-Vema 12-107 (VM) yellow-Bermuda Rise (BR) light gray-Barbados (BB) dark gray-Cariaco Basin (CB). White circle pinpoints the Dry Tortugas (DT). A: Historic North Atlantic hurricane tracks passing within 65 nm of our site at major hurricane strength (96 kn, 1 min maximum sustained wind) since 1848 CE (Knapp et al., 2010).
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