Geochemical and palynological results of IODP Hole 302-M0004A from Lomonosov Ridge, Arctic Ocean

• Main Authors: Sluijs, Appy, Schouten, Stefan, Donders, Timme H, Schoon, Petra L, Röhl, Ursula, Reichart, Gert-Jan, Sangiorgi, Francesca, Kim, Jung-Hyun, Sinninghe Damsté, Jaap S, Brinkhuis, Henk
• Format: Dataset
• Language: English
• Published: PANGAEA 2010
• Subjects: 302-M0004A; ACEX-M4A; Arctic Coring Expedition; ACEX; Arctic Ocean; Exp302; Integrated Ocean Drilling Program / International Ocean Discovery Program; IODP; Vidar Viking; Arctic; Lomonosov Ridge
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.735745; https://doi.org/10.1594/PANGAEA.735745

Several episodes of abrupt and transient warming, each lasting between 50,000 and 200,000 years, punctuated the long-term warming during the Late Palaeocene and Early Eocene (58 to 51 Myr ago) epochs**1,2. These hyperthermal events, such as the Eocene Thermal Maximum 2 (ETM2) that took place about 53.5 Myr ago**2, are associated with rapid increases in atmospheric CO2 content. However, the impacts of most events are documented only locally**3,4. Here we show, on the basis of estimates from the TEX86' proxy, that sea surface temperatures rose by 3-5 °C in the Arctic Ocean during the ETM2. Dinoflagellate fossils demonstrate a concomitant freshening and eutrophication of surface waters, which resulted in euxinia in the photic zone. The presence of palm pollen implies**5 that coldest month mean temperatures over the Arctic land masses were no less than 8 °C, in contradiction of model simulations that suggest hyperthermal winter temperatures were below freezing**6. In light of our reconstructed temperature and hydrologic trends, we conclude that the temperature and hydrographic responses to abruptly increased atmospheric CO2 concentrations were similar for the ETM2 and the better-described Palaeocene-Eocene Thermal Maximum**7,8, 55.5 Myr ago.