HR: 1340h
AN: PP43A-0660    [Abstracts]
TI: Eastern Mediterranean Ecosystem and Sedimentation Response to Holocene Climate Changes
AU: * Schmiedl, G H
EM: schmiedl@rz.uni-leipzig.de
AF: Leipzig University, Institute of Geophysics and Geology, Talstrasse 35, Leipzig, 04103 Germany
AU: Ehrmann, W U
EM: ehrmann@rz.uni-leipzig.de
AF: Leipzig University, Institute of Geophysics and Geology, Talstrasse 35, Leipzig, 04103 Germany
AU: Kuhnt, T
EM: tkuhnt@rz.uni-leipzig.de
AF: Leipzig University, Institute of Geophysics and Geology, Talstrasse 35, Leipzig, 04103 Germany
AU: Hamann, Y
EM: yhamann@rz.uni-leipzig.de
AF: Leipzig University, Institute of Geophysics and Geology, Talstrasse 35, Leipzig, 04103 Germany
AU: Hemleben, C
EM: christoph.hemleben@uni-tuebingen.de
AF: Tuebingen University, Institute of Geosciences, Sand 6/7 - IfG, Kernlabor und -Lager, Tuebingen, 72076 Germany
AB: Various proxy records from late Glacial and Holocene sediments of the eastern Mediterranean Sea reveal significant temporal and spatial variability suggesting that the different sub-basins were influenced by different oceanographic and climate regimes. In the North Aegean Sea, environmental conditions are controlled by sea level, exchange of water masses between the Black Sea and Aegean Sea, and river discharge from southeastern Europe. Benthic foraminiferal faunas of moderate diversity occur throughout sapropel S1 indicating the persistence of deep-water formation in this area during the whole studied time interval. In the South Aegean Sea and the Levantine Sea, environmental conditions are dominated by the counterclockwise circulation pattern, and by the eolian and riverine sediment input from Africa. In these areas sapropel S1 formation was accompanied by intervals of severe restriction of deep-water ventilation. Most proxies exhibit abrupt and multi-centennial to millennial fluctuations indicating the impact of short-term climate changes on the different environmental processes. In the North Aegean Sea, two particularly humid phases appear in the middle to late Holocene and are reflected by shifts in clay mineral composition and the foraminiferal stable isotope signals. During these time intervals, river discharge increased and resulted in restriction of local deep-water ventilation as indicated by an increase of low-oxygen-tolerant benthic taxa. In the South Aegean Sea, periodic changes in clay mineral assemblage are linked to fluctuations in the Nile discharge and humidity of the catchment in eastern Africa. Our results demonstrate that the Eastern Mediterranean Sea is influenced by both mid-latitude European and tropical African climate variability. Herewith, linkages between climate systems such as the North Atlantic Oscillation and the African monsoon circulation can be evaluated.
DE: 4901 Abrupt/rapid climate change (1605)
DE: 4936 Interglacial
DE: 4962 Thermohaline
SC: Paleoceanography and Paleoclimatology [PP]
MN: Fall Meeting 2005