A high‐resolution radiolarian‐derived paleotemperature record for the Late Pleistocene‐Holocene in the Norwegian Sea

Polycystine radiolarians are used to reconstruct summer sea surface temperatures (SSSTs) for the Late Pleistocene‐Holocene (600–13,400 14 C years BP) in the Norwegian Sea. At 13,200 14 C years BP, the SSST was close to the average Holocene SSST (∼12°C). It then gradually dropped to 7.1°C in the Younger Dryas. Near the Younger Dryas‐Holocene transition (∼10,000 14 C years BP), the SSST increased 5°C in about 530 years. Four abrupt cooling events, with temperature drops of up to 2.1°C, are recognized during the Holocene: at 9340, 7100 (“8200 calendar years event”), 6400 and 1650 14 C years BP. Radiolarian SSSTs and the isotopic signal from the GISP2 ice core are strongly coupled, stressing the importance of the Norwegian Sea as a mediator of heat/precipitation exchange between the North Atlantic, the atmosphere, and the Greenland ice sheet. Radiolarian and diatom‐derived SSSTs display similarities, with the former not showing the recently reported Holocene cooling trend.