Fig. 3: OS age versus depth with the 16 absolute U/Th ages and associated error bars ( ± 2σ; <1.4%).

The OS chronology was created using COPRA (v. 1.16)89 in MATLAB (v. R2021b). Blue and Orange shading represents timing of Heinrich Layer 1 stages (1.1 and 1.2) and the Bølling–Allerød (B/A) warm interval, respectively. Notice OS growth rate has a three-phase variability, with the fastest growth occurring during the last 400 yrs of the record (14.3–14.7 kyrs BP), the slowest growth between 14.7 and 16.1 kyrs BP, and relatively slow growth from 16.1 kyrs BP until the beginning of the record at 17.6 kyrs BP.