The end of the last interglacial period, ~118 kyr ago, was characterized by substantial ocean circulation and climate perturbations resulting from instabilities of polar ice sheets. These perturbations are crucial for a better understanding of future climate change. The seasonal temperature changes of the tropical ocean, however, which play an important role in seasonal climate extremes such as hurricanes, floods and droughts at the present day, are not well known for this period that led into the last glacial. Here we present a monthly resolved snapshot of reconstructed sea surface temperature in the tropical North Atlantic Ocean for 117.7±0.8 kyr ago, using coral Sr/Ca and d18O records. We find that temperature seasonality was similar to today, which is consistent with the orbital insolation forcing. Our coral and climate model results suggest that temperature seasonality of the tropical surface ocean is controlled mainly by orbital insolation changes during interglacials.

Fossil coral / U/Th-Age: 117.7 (+/-0.8) kyr before the year of measurement (which is AD 2009) / Time period: 20 years around 118 kyr ago / Internal chronology starts at base (oldest part) of coral / Data acquired through projects CaribClim (Seasonality and interannual to centennial climate variability in the Caribbean during the last interglacial - Combining coral records, stalagmite records and climate models (CaribClim II)) and Saisonalität und zwischenjährliche Klimavariabilität in der Karibik während des letzten Interglazials rekonstruiert anhand von Korallenzeitreihen.

Supplement to: Felis, Thomas; Giry, Cyril; Scholz, Denis; Lohmann, Gerrit; Pfeiffer, Madlene; Pätzold, Jürgen; Kölling, Martin; Scheffers, Sander R (2015): Tropical Atlantic temperature seasonality at the end of the last interglacial. Nature Communications, 6, 6159