Fig. 6: Speleothem records from South America and their phasing relationship with Asian summer monsoon records during AHP2 and SAHP2 terminations.

a–d SASM speleothem δ¹⁸O records from Marota Cave (MAG, this study), Paixão Cave (PX-07, this study), Cueva del Diamante Cave (NAR-C, this study and ref. 8), and Botuverá Cave (BTV-4C, this study). e ASM speleothem δ¹⁸O record from Cherrapunji Cave (this study) (note the inverted y-axis). Cave locations are shown in Fig. 2f, g. Error bars in (c) depict ²³⁰Th dates and 2σ errors of the NAR-C record. Red dots and associated error bars in (a) and (c–e) indicate timing and combined uncertainties (2σ) of the change points in speleothem δ¹⁸O records (Supplementary Table 2), red lines in (a) and (c–e) show the ramps and break lines generated by Ramp-fitting⁴⁴ and BREAKFIT⁴⁵ algorithms (see Methods). The red arrow depicts the trend in the PX-07 record during the SAHP2 termination. Vertical bars are the same as in Fig. 2. f Probability density functions of spatial age offsets between the start of stage I in ASM and the initial drying in SASM (SASM minus ASM) based on speleothem records reported in this study (Supplementary Table 2). Shadings indicate the 95.4% intervals (2σ uncertainty). g is the same as in (f) but for the comparisons at the end of AHP2 and SAHP2 (Supplementary Table 2). AHP2 Asian Heinrich Period 2, SAHP2 South American Heinrich Period 2, ASM Asian summer monsoon, SASM South American summer monsoon, ISM Indian summer monsoon.