Figure 3. Deglacial δ¹¹B, pH and pCO₂ variability in the equatorial Pacific.

(a) Reported δ¹¹B values of planktonic foraminifera with 2σ uncertainty from ERDC-92 (ref. ¹⁰). Age model is from the original publication. (b) In situ pH reconstructed from δ¹¹B of fossil Porites spp. using our new calibration. Red and green circles are from Tahiti by this study and Douville et al.¹¹, respectively. Blue circles are from Marquesas by Douville et al.¹¹ after correction by +0.04 pH units. (c) Derived pCO₂ of surface water around equatorial South Pacific Ocean (same colors as b) and atmospheric pCO₂ on the GICC05 timescale¹. All error bars are 2σ. YD, Younger Dryas; B/A, Bølling/Allerød; ACR, Antarctic Cold Reversal; HS1, Heinrich Stadial 1; LGM, Last Glacial Maximum.