Fig. 3: Changes in ocean feedbacks and climate in both Atlantic polar regions across the MPT.
From: Glacial dysoxia in the deep subpolar North Atlantic during the Mid-Pleistocene Transition
North Atlantic IODP Site U1314 surface and deep-water records (this study) compared with AMOC, sea-level and pCO2 estimates across the MPT. Black numbers indicate interglacials (odd) and glacials (even) marine isotope stages (MIS). Yellow vertical bars correspond to interglacial stages. A IODP Site U1314 IRD/g (dark blue line)28 and Northern Hemisphere ice-volume reconstruction (dashed light blue line)15, (B) deep-sea benthic foraminifera species related to well-ventilated bottom waters (dark red line), (C) bulk Mn/Al ratio (black line) and P reactive (orange line). Error bars are replicate 1 SD (Methods). D Site U1385 O2 concentration based on ∆δ13Cwue-aff and Mn/Ca ratio (golden line) in benthic foraminifera (Uvigerina spp.) authigenic coatings (purple circles)23. The O2 reconstruction is truncated at 235 μmol kg−1, above which the calibration is unreliable. E Site 60721,22 (dark blue line) and Site U1479 εNd11 (brown line). F Site 1090 εNd19 (dark purple line) and relative abundance of C37:488 (light purple line). G Site 1094 sedimentary Ba/Al measured by core scanning XRF40 (light orange line) and Mn/Ca ratio in planktonic foraminifera (N. pachyderma) authigenic coatings (pink dots), where Mn/Ca > 100–200 µmol/mol can be indicative of potential Mn-Fe coating material [17; note that axis is truncated between 1200 and 1700] and Southern Hemisphere ice-volume reconstruction (dashed pink line)15. H Site U1446 reconstructed atmospheric CO2 concentration (CO2FA) based on fatty acid δ13C (black line)5. The vertical gray bar highlights MIS 24–MIS 22.
