Indroduction

The central research theme is the reconstruction of current, production, and sedimentation systems in the South Atlantic over the past 300,000 years. From the results, inferences will be drawn concerning the processes and causal relationships between warm- and cold-period climatic changes in the oceans, on the continents, and in the atmosphere. The time period for the investigations includes the last three large climatic cycles with warm maxima at 6,000, 12,000, and 215,000 years bp, which were characterized by extreme volume changes in the polar ice caps.

According to widely accepted theory, cyclic changes in the earth`s orbital patterns relative to the sun are primarilyresponsible for these dramatic climate changes. The past alteration of warm and cold periods cannot, however, be completely explained by variations in the earth`s orbital pattern. Positive and negative feedback effects in oceanic regions and on the continents, as well as between the ocean and atmosphere must also be investigated. These effects and the extent of their influence on climate change are presently not very well understood.

The individual questions to be adressed therefore concern interactions among multiple factors and processes, including algae production in the ocean, vegetation changes (CO₂ budget in the ocean-land biosphere and atmosphere), oceanic circulation, heat transport, fresh water input, ice cover, and global energy budget.

Books published by the SFB261:

• Wefer, G.; Berger, W. H.; Siedler, G.; Webb, D. J. (Eds.), 1996, The South Atlantic - Present and Past Circulation, Springer Verlag Berlin Heidelberg, 644 pp.
• Fischer, G.; Wefer, G. (Eds.), 1999, Use of Proxies in Paleoceanography, Examples from the South Atlantic, Springer Verlag Berlin Heidelberg New York Tokyo, 735 pp. Data
• Schulz, H. D.; Zabel, M. (Eds.), 2000, Marine Geochemistry, Springer Verlag Berlin Heidelberg New York Tokyo, 455 pp.
• Wefer, G.; Berger, W. H.; Behre, K.-E.; Jansen, E. (Eds.), 2002, Climate Development and History of the North Atlantic Realm, Springer Verlag Berlin Heidelberg New York Tokyo, 486 pp.
• Wefer, G.; Billet, D.; Hebbeln, D.; Jorgensen, B. B.; Schlüter, M.; Weering, T. C. E. V. (Eds.), 2003, Ocean Margin Systems, Springer Verlag Berlin Heidelberg New York Tokyo, 495 pp.
• Wefer, G.; Mulitza, S.; Ratmeyer, V. (Eds.), 2004, The South Atlantic in the Late Quaternary, Reconstruction of Material Budgets and Current Systems, Springer Verlag Berlin Heidelberg New York Tokyo, 722 pp. Data