A cold and fresh ocean surface in the Nordic Seas during MIS 11: Significance for the future ocean

作者：Kandiano Evgenia S^*; van der Meer Marcel T J; Bauch Henning A; Helmke Jan; Damste Jaap S Sinninghe; Schouten Stefan

来源：Geophysical Research Letters, 2016, 43(20): 10929-10937.

DOI：10.1002/2016GL070294

• temperature reconstructions
• reconstructions of salinity changes
• the Nordic Seas
• MIS 11

Paleoceanographical studies of Marine Isotope Stage (MIS) 11 have revealed higher-than-present sea surface temperatures (SSTs) in the North Atlantic and in parts of the Arctic but lower-than-present SSTs in the Nordic Seas, the main throughflow area of warm water into the Arctic Ocean. We resolve this contradiction by complementing SST data based on planktic foraminiferal abundances with surface salinity changes using hydrogen isotopic compositions of alkenones in a core from the central Nordic Seas. The data indicate the prevalence of a relatively cold, low-salinity, surface water layer in the Nordic Seas during most of MIS 11. In spite of the low-density surface layer, which was kept buoyant by continuous melting of surrounding glaciers, warmer Atlantic water was still propagating northward at the subsurface thus maintaining meridional overturning circulation. This study can help to better constrain the impact of continuous melting of Greenland and Arctic ice on high-latitude ocean circulation and climate.

• 出版日期2016-10-28