Fig. 2

Marine records of the Chiba composite section (CbCS) showing a δ¹⁸O (red) and Mg/Ca-based winter temperature (green) for G. bulloides, b δ¹⁸O (purple) and Mg/Ca-based winter temperature (green) for G. inflata (Suganuma et al. 2018; Haneda et al. 2020a), c δ¹³C for G. bulloides (blue) and for G. inflata (orange), d Δδ¹³C_inf-bul (yellow) and Δδ¹⁸O_inf-bul (black), e, f microfossil relative abundances for e radiolarians (Suganuma et al. 2018 and this study), f calcareous nannofossils (Kameo et al. 2020), g benthic δ¹⁸O in the CbCS (Suganuma et al. 2018), h comparison to global mean δ₁₈O of water (δ₁₈O_w) of Elderfield et al. (2012) (blue) and the benthic δ¹⁸O stack of Lisiecki and Raymo (2005) (black). Younger Dryas-type cooling events during Termination IX and distinct millennial events in δ¹⁸O of G. bulloides during MIS 19a are highlighted in gray and yellow. Arrows in Fig. 3c represent negative peaks in δ¹³C of G. inflata mentioned in the text. Figure 2 illustrates the data from 801 to 751 ka.