Reconstruction of past climatic events using principal component analysis of the trace element profiles in a sediment core (Joides Basin, Antarctica)

Principal Component Analysis has been used to characterize the climatic events in a sediment core on the basis of chemical analysis. We have analysed 78 samples from a 473 cm marine sediment core collected from the Joides Basin, Ross Sea- Antarctica. These were collected during an oceanographic sampling survey in 2002-2003 within the frame of the XVIII Italian expedition to Antarctica. Several trace elements were determined (Ag, Al, As, Ba, Be, Cd, Co, Cr, Cu, Fe, Ga, Li, Mn, Mo, Ni, Pb, Sb, Se, Th, Tl, U, V, Y, Zn and REE). One of the extracted components highlights a succession of peaks, which correspond to climatic events clearly recognized elsewhere. This trend is in agreement with TOC and Biogenic silica core profiles. Core chronology has been established on the basis of correlations with dated samples in the same area. The sediments taken, span from the last glacial maximum to present. During the transition from the LGM to the Holocene a climatic event that can be attributed to the Antarctic Cold Reversal (ACR) has been observed.