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.
/ The necessity to tailor information becomes increasingly urgent as the information revolution continues to generate ever-increasing flows of data and so-called information. From European experiences, a new approach for monitoring system design is suggested in this paper. In this approach, careful and detailed specification of information needs is a major contributing factor to the effectiveness of information products. To develop better specifications for information products, the process of collecting and transforming data into useful information requires careful thought and guidance. A dialogue between information users on one hand and information producers on the other is essential. This dialogue can be based on the information cycle, describing the continuous process from specifying information needs for water management and a strategy to collect information through data collection and data analysis up to utilization of information by water management. By following the respective steps in the information cycle, the process of information gathering can be completed. The cyclic character provides a quantitative means of connecting monitoring system design and operations with the information expectations and/or products required by management.
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