Figures 2a and b. Planktic 14C records of sediment cores PS2644 and GIK232074 plotted vs. core depth; for core locations see Fig. 1. Planktic 14C plateaus (horizontal boxes) are compared to atmospheric (atm) 14C plateau suite of Lake Suigetsu (Bronk Ramsey et al., 2020), where calendar ages of plateau boundaries (and average atmospheric 14C ages) are given below in cal. ka BP (before 1950 AD). Atmospheric plateau 4a directly reflects the switch in Nordic Seas flow geometry ~18.6–18.4 cal. ka (before 1950 AD). Local planktic reservoir ages (in blue) result from the difference between the average raw 14C age of planktic 14C plateaus measured in the core and the 14C age of equivalent atmospheric 14C plateaus numbered 1 – 6 (numbers in brackets). Top panel shows units of the 1st derivative (14C yr per m core depth) and 1-σ uncertainty range, with high values indicating 14C jumps and 14C plateaus (numbered in red) constrained at ’half-height’ by asterisks (as defined in Sarnthein et al. 2015). Green dots display paired benthic 14C ages. B/A = Bølling-Allerød; HS-1a+b = Heinrich Stadial 1 a and b; LGM = Last Glacial Maximum. Sedimentation rates are based on cal. ages of 14C plateau boundaries. Red dotted line in Fig. 2b shows local planktic δ18O record of N. pachyderma sin. (Voelker, 1999)