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Abstract: We used multiple paleoceanographic proxies to examine sediments from the Blake Outer Ridge (ODP Site 1058, 2996m water depth) that span the MIS 13–10 time interval. Benthic foraminiferal δ 13C, organic δ 13C, and total δ 15N values are lower in MIS 12 and 10 than in MS 11, and indicate glacial–interglacial changes in both thermohaline circulation and ocean-wide biogeochemical processes that affect deep and surface waters. Three time intervals of higher productivity, as evidenced by higher organic carbon accumulation rates (1.6–4.5gm−2 yr−1), occur at the end of MIS 13 and during the early and late parts of MIS 11, in association with the transition from obliquity minima to obliquity maxima. Benthic faunas in these intervals show a distinct increase in opportunistic species that feed on phytodetritus (Epistominella exigua) or are adapted to elevated but intermittent organic carbon fluxes (Bulimina aculeata and Bulimina marginata) and that imply episodes of recurrent phytoplankton blooms at the surface and consequent export of labile organic matter to the seafloor. Late interglacial MIS 11.3 is a time of low organic carbon fluxes (<0.5gm−2 yr−1) and is characterized by higher abundances of epifaunal benthic foraminiferal taxa (Cibicidoides wuellerstorfi, Gyroidina spp., Gyroidinoides spp. and Nuttallides umbonifera) that are typical of modern oligotrophic environments. In contrast, during glacial MIS 12 and 10 higher organic carbon fluxes (>0.5gm−2 yr−1) and benthic assemblages dominated by infaunal taxa (Uvigerina spp. and Bulimina alazanensis) indicate sustained organic carbon delivery and diminished pore water oxygenation. [ABSTRACT FROM AUTHOR]

Well-dated multidecadal- to centennial-scale sediment records from the subarctic northwest Pacific show that the early deglacial 18.5-15.0 ka was marked by 3 pronounced short-term warmings of ∼5 °C. They lasted 500-1500 yr each and were coeval with early to late stages of cold Heinrich event 1 in the North Atlantic. These regional climate windows may have promoted a pre-Clovis emigration of people from the cold-arid monsoon climate in East Asia to the climatically more favorable, then-emerged Beringian and Aleutian shelf regions and the Americas, as suggested by archeological findings. [ABSTRACT FROM AUTHOR]

The article discusses the origin of thermostat in the North Atlantic Ocean. The paleoceanographers assumed that thermostat switch which began to melt the world over the last ice age lay somewhere in the North Atlantic Ocean. However, new evidence from the tropical places that it lay in the waters around Antarctica. According to a paleoceanographer Lowell Stott, studying the origin of it comes down to timing, and determining the timing of climate events can be tough as warming in the tropics is recorded in marine sediments, whereas warming in Antarctica is recorded in glacial ice.