Millennial-scale sea surface temperature variability in the western tropical North Atlantic from planktonic foraminiferal census counts

Planktonic foraminiferal census counts are used to construct high-resolutio n sea surface temperature (SST) and subsurface (thermocline) temperature re cords at a core site in the Tobago Basin, Lesser Antilles. The record is us ed to document climatic variability at this tropical site in comparison to middle- and high-latitude sites and to test current concepts of cross-equat orial heat transports as a major player in interhemispheric climate variabi lity. Temperatures are estimated using transfer function and modern analog techniques. Glacial - maximum cooling of 2.5 degrees -3 degreesC is indicat ed; maximum cooling by 4 degreesC is inferred for isotope stage 3. The SST record displays millennial-scale variability with temperature jumps of up t o 3 degreesC and closely tracks the structure of ice-core Dansgaard/Oeschge r cycles. SST variations in part of the record run opposite to the SST evol ution at high northern latitude sites, pointing to thermohaline circulation and marine heat transport as an important factor driving SST in the tropic al and high-latitude Atlantic, both on orbital and suborbital timescales.