Figure 2
Age plots of paleoceanic environment proxies. (a) Diatom-based salinity from Osaka Bay13, (b) planktic δ18O from the Chiba Section (TB2), (c) 10-yr resolution Ca/Ti ratio from the Chiba Section (TB2) (see Methods), (d) planktic δ18O from IODP site U1313, mid-latitude North Atlantic12, and (e) ice volume variation, calculated at 15 ka for the mean time constant, and 0.6 and 0.4 for the nonlinearity parameter46 (Supplementary Information). In (a–d), the common millennial-scale features possibly reflecting sea-level rise and/or warming are labeled A to K. In (a), the climate features for Osaka Bay, shown by bars and solid squares, are based on pollen data11. In (c), the oxic events numbered 1 to 10 in Fig. 1 are shown. In (d), sporadic and continuous occurrences of iceberg discharge are shown by open arrowheads and open rectangles, respectively (after ref. 12). Short-lived sporadic iceberg discharge events during the MIS19 interglacial in Fig. 1 are labeled α to φ. For the plot of U1313 data, the MBB is shown at an age/depth corrected upward by 16 cm, an average lock-in depth for deep-sea cores47, but the MBB level is not corrected in the plots of Osaka Bay and Chiba (TB2) data with a.r. higher than 60 cm/ka.
