Tropical Atlantic stratification response to late Quaternary precessional forcing

The upper ocean circulation in the western tropical Atlantic (WTA) is responsible for northward cross-equatorial heat transport as part of Meridional Overturning Circulation (AMOC). This influenced by thermocline and stratification. Although seasonal stratification WTA precession-driven, existence an orbital pacemaker changes entire stratification, which comprises main thermocline, remains elusive. Here, we present a 300 ka-long record temperature based on oxygen isotopes (δ18O) Mg/Ca planktonic foraminifera. Our Δδ18O between Globigerinoides ruber Globorotalia truncatulinoides, representing shows robust precession pacing, where strong was linked to high summer insolation Northern Hemisphere (precession minima). Mg/Ca-based temperatures support that dominated temperature. We new mechanism explain during maxima, Intertropical Convergence Zone shifts northward, developing negative wind stress curl anomaly Atlantic. This, turn, pulls up pushes South Subtropical Gyre southwards, increasing north gyre. supported experiments performed with Community Earth System Model (CESM1.2). Finally, hypothesize precession-driven may affect flow into North