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Abstract. We studied variations in terrigenous input and sea surface temperature over the last 208 ka using a multiproxy approach, involving direct comparison of terrigenous and marine molecular biomarker, foraminiferal abundance, and other sedimentological data for the same horizons in a single northeast Atlantic core (core T88-9P; 48o23 ' N, 25o05 ' W, 3193 m water depth, 790 cm core length) with a well-resolved •5180 stratigraphy. The abundances of three landderived, long-chain compound classes, the n-alkanes (C27, C29, and C 3 l), the n-alkanoic acids (C24, C26, and C28), and the n-alkanols (C24, C26, and C28) show glacial/interglacial related changes in the past 208 ka which generally parallel the weight percent noncarbonate. The abundances of these three compound classes are higher in glacial than in interglacial sediments. Such changes are consistent with the expected higher dust inputs during glaciations as well as enhanced advection of particulate matter in current systems. Ice-rafted debris (Heinrich events) may also contribute to the terrigenous biomarker record. The sea surface temperature (SST) signals derived from the alkenone unsaturation index (uK'37) give an average SST during interglacial periods of 13øC, which is about 3-4øC higher than the average glacial SST estimate. The uK'37 -derived SST values dropped markedly in some Heinrich layers, while sometimes leading the onset of the layer; the percent Neogloboquadrina pachyderma(s), which is another frequently used qualitative temperature proxy, generally shows maxima coinciding with the layers. Our results show that most Heinrich layers were produced during times of intensely cold waters in the eastern North Atlantic. They demonstrate that sufficient alkenones are present in the sediments for alkenone stratigraphy to be used as a tool for the assessment of short-term variations in sea surface temperatures even in these oligotrophic North Atlantic waters.

Modern and fossil freshwater bivalves from north-eastern Peru are investigated to reconstruct seasonal rainfall patterns in Miocene Amazonia. Oxygen isotope variation in incremental growth bands of fossil bivalves reflects past hydrological conditions in the Miocene Climate Optimum (MCO), when the world was warmer than today. A calibration experiment was conducted on a modern bivalve. Modern river dwelling Triplodon corrugatus shows large amplitudinal changes in y 18 O, which mirror the seasonal variation in rainfall as a result of the annual migration cycle of the Inter Tropical Convergence Zone (ITCZ). Growth incremental oxygen isotope records of Miocene Amazonian Diplodon aff. longulus bivalves show strikingly similar patterns. This suggests that the seasonal migration of the ITCZ and the intensity of the hydrological cycle in the MCO were comparable to today. The implications are that humid climate conditions sufficient to sustain a rainforest ecosystem already existed~16 Ma ago. D

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