Figure 5
From: Southern Ocean contribution to both steps in deglacial atmospheric CO2 rise
Schematic South Pacific overturning and carbon cycling. (a) Last Glacial Maximum. Sluggish CDW circulation with separated lower and upper cells. Lower DIC-rich cell with very depleted ΔΔ14C values8. (b) Heinrich Stadial 1 (HS1) and Younger Dryas (YD) scenario. Progressive increase in deep-water overturning results in the release of CO2 from DIC-rich and high pCO2 CDW. This release causes the transient rises in AAIW [CO32−] observed in downstream PS75/104-1 indicated by purple dot. Green arrow—input of freshwater into the upper cell15, red arrow—input of highly saline brine into the lower cell33.
