Diatom percentage abundances for sediment core KH-10-7 COR1GC from the Conrad Rise, Southern Ocean@en

Centennial and millennial scale variability of Southern Ocean temperature is poorly known, due to both short instrumental records and sparsely distributed high-resolution temperature reconstructions, with evidence for past temperature variability instead coming mainly from ice core records. Here we present a high-resolution (~ 60 year) record of diatom abundance from the western Indian sector of the Southern Ocean that spans the interval 14.2 to 1.0 ka BP (calibrated kiloyears before present). The results show the dominant species are Fragilariopsis kerguelensis and Thalassiosira lentiginosa, with accompanying species typical of the Polar Front Zone and Permanent Open Ocean Zone. Species associated with warmer temperatures were most abundant in the period 12-9.5 ka BP, while species associated with lower temperatures were abundant at 14.2-9.5 ka BP.