NOAA/WDS Paleoclimatology - LoDico et al. 2006 Gulf of Mexico MD02-2550 Early Holocene Mg/Ca and d18O Data and SST Reconstruction

An early Holocene record from the Gulf of Mexico (GOM) reveals climatic and hydrologic changes during the interval from 10.5 to 7 thousand calendar years before present from paired analyses of Mg/Ca and δ18O on foraminiferal calcite. The sea surface temperature record based on foraminiferal Mg/Ca contains six oscillations and an overall ∼1.5°C warming that appears to be similar to the September–March insolation difference. The δ18O of seawater in the GOM (δ18OGOM) record contains six oscillations, including a −0.8‰ excursion that may be associated with the “8.2 ka climate event” or a broader climate anomaly. Faunal census records from three GOM cores exhibit similar changes, suggesting subcentennial-scale variability in the incursions of Caribbean waters into the GOM. Overall, our results provide evidence that the subtropics were characterized by decadal- to centennial-scale climatic and hydrologic variability during the early Holocene.