FN Archimer Export Format PT J TI Similar millennial climate variability on the Iberian margin during two early Pleistocene glacials and MIS 3 BT AF BIRNER, B. HODELL, D. A. TZEDAKIS, P. C. SKINNER, L. C. AS 1:1;2:1;3:2;4:1; FF 1:;2:;3:;4:; C1 Univ Cambridge, Dept Earth Sci, Godwin Lab Palaeoclimate Res, Cambridge CB2 3EQ, England. UCL, UCL Dept Geog, London, England. C2 UNIV CAMBRIDGE, UK UNIV COLL LONDON, UK IF 3.254 TC 19 UR https://archimer.ifremer.fr/doc/00421/53289/54199.pdf https://archimer.ifremer.fr/doc/00421/53289/54200.pdf LA English DT Article CR IMAGES V LEG 1-MD114 IMAGES V LEG 4-MD114 BO Marion Dufresne DE ;millennial variability;interhemispheric linkage;Iberian margin;early Pleistocene AB Although millennial-scale climate variability (<10ka) has been well studied during the last glacial cycles, little is known about this important aspect of climate in the early Pleistocene, prior to the Middle Pleistocene Transition. Here we present an early Pleistocene climate record at centennial resolution for two representative glacials (marine isotope stages (MIS) 37-41 from approximately 1235 to 1320ka) during the 41ka world at Integrated Ocean Drilling Program Site U1385 (the Shackleton Site) on the southwest Iberian margin. Millennial-scale climate variability was suppressed during interglacial periods (MIS37, MIS39, and MIS41) and activated during glacial inceptions when benthic O-18 exceeded 3.2. Millennial variability during glacials MIS38 and MIS40 closely resembled Dansgaard-Oeschger events from the last glacial (MIS3) in amplitude, shape, and pacing. The phasing of oxygen and carbon isotope variability is consistent with an active oceanic thermal bipolar see-saw between the Northern and Southern Hemispheres during most of the prominent stadials. Surface cooling was associated with systematic decreases in benthic carbon isotopes, indicating concomitant changes in the meridional overturning circulation. A comparison to other North Atlantic records of ice rafting during the early Pleistocene suggests that freshwater forcing, as proposed for the late Pleistocene, was involved in triggering or amplifying perturbations of the North Atlantic circulation that elicited a bipolar see-saw response. Our findings support similarities in the operation of the climate system occurring on millennial time scales before and after the Middle Pleistocene Transition despite the increases in global ice volume and duration of the glacial cycles. PY 2016 PD JAN SO Paleoceanography SN 0883-8305 PU Amer Geophysical Union VL 31 IS 1 UT 000370351800012 BP 203 EP 217 DI 10.1002/2015PA002868 ID 53289 ER EF