HR: 0800h
AN: PP41B-0642    [Abstracts]
TI: Evidence for Climate-related Surface Ocean Changes in the North Atlantic During the Last Interglacial Period
AU: Kandiano, E
EM: ekandiano@ifm-geomar.de
AF: IFM-GEOMAR, Wischhofstrasse 1-3 , Kiel, 24148 Germany
AU: * Bauch, H
EM: hbauch@ifm-geomar.de
AF: Mainz Academy of Sciences, Humanities and Literature, c/o IFM-GEOMAR, Wischhofstrasse 1-3, Kiel, 24148 Germany
AB: Deep ocean records from the North Atlantic define the last interglaciation (MIS5e) a period of relative stability with good similarity to the present warm period (MIS1). In order to obtain more in-depth climatic information a newly developed analysis of rare planktic foraminiferal species was applied. This analysis considers those species which do not persist continuously in a record but appear in low amounts only under particular environmental conditions. At our core location (53N/20W), the rare species assemblage consists of tropical and subtropical representatives which occur in the middle latitudes during times of enhanced water advection from the south, thus giving evidence of changes in the strength of the North Atlantic Drift during interglacial times which otherwise remains beyond the sensitivity of conventional proxies. Using this new analysis, paired with O-isotope records of different species, documents a new picture of surface ocean evolution in the N. Atlantic during MIS5e. Highest sea surface temperatures (SSTs) were present during early MIS5e, directly following ice sheet melting of the preceding glaciation. A first major surface change occurred after 4 ky, whereas relative stability in global ice volume continued for another 3-4 ky before SSTs further decreased during the transition into the next cold stage. Because all records of MIS5e are clearly non-analogy compared to MIS1 a different ocean-atmosphere circulation regime is regarded responsible, which affected both the surface water mass configuration of the North Atlantic and the heat-moisture transfer into Europe.
DE: 4901 Abrupt/rapid climate change (1605)
DE: 4936 Interglacial
DE: 4944 Micropaleontology (0459, 3030)
DE: 4954 Sea surface temperature
SC: Paleoceanography and Paleoclimatology [PP]
MN: Fall Meeting 2005