Iberian Margin surface ocean cooling led freshening during Marine Isotope Stage 6 abrupt cooling events.

ABSTRACT: The high-resolution paleoclimate records on the Iberian Margin provide an excellent archive to study the mechanism of abrupt climate events. Previous studies on the Iberian Margin proposed that the surface cooling reconstructed by the alkenone-unsaturation index coincided with surface water freshening inferred from an elevated percentage of tetra-unsaturated alkenones, C_37:4%. However, recent data indicate that marine alkenone producers, coccolithophores, do not produce more C_37:4 in culture as salinity decreases. Hence, the causes for high C_37:4 are still unclear. Here we provide detailed alkenone measurements to trace the producers of alkenones in combination with foraminiferal Mg/Ca and oxygen isotope ratios to trace salinity variations. The results indi

SUBMITTER: Zhang H 

PROVIDER: S-EPMC10477208 | biostudies-literature | 2023 Sep

REPOSITORIES: biostudies-literature