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Optical beam transmittance meters integrated into Aanderaa current meters were used to measure long time series of suspended matter concentration simultaneously with current velocity and salinity in the turbidity maximum of the Weser estuary (shallow coastal plain estuary of the North Sea). They cover the spectrum from 10 min to several months. The time histories of concentrations and fluxes are discussed for characteristic locations within the turbidity maximum. The analyses demonstrate that the tidal dynamics of deposition into and resuspension of particles from temporally and spatially limited material sources at the bottom is the dominant process in the turbidity maximum while the nontidal gravitational circulation acts as a long-term source and sink. There is a remarkable repeatability of concentration patterns during similar discharge conditions. the tidal excursion can cause tidal fluctuations of about 10%o 14,373 14,374 GRABEMANN AND KRAUSE' TIME SERIES OF SUSPENDED MATTER ß ••i• OFE Bremerhaven NORDENHAM ,"

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We observed short‐term peaks in pigment fluorescence and backscattering using optical sensors combined with time‐series sediment traps at ∼900‐m depth at an oligotrophic site in the Canary Island region. These events were observed in late winter to early spring and lasted only a few hours to a few days. The events generally coincided with late winter to early spring flux maxima recorded by the traps. Surprisingly, microscopic analyses showed no evidence of sedimentation of intact phytoplankton cells during the fluorescence peaks. However, we observed well‐preserved zooplankton fecal pellets containing densely packed coccoliths and, presumably, large amounts of chlorophyll‐derived pigments.

[1] Conductivity-temperature-depth transects across the Greenland Sea and Fram Strait provide geostrophic shear velocity profiles, which were absolutely referenced using the simultaneous measurements from a vessel-mounted acoustic Doppler current profiler. The measurements are performed mainly in 1997, with supplements in 1998, 1995, and 1994. The observations confirm that all currents within the area have a strong barotropic component so that calculations based on the geostrophic method underestimate the transports considerably. Particulars for the transports of mass and heat are given for all individual and total water masses in the area. Meanders and eddies on horizontal scales between 20 and 70 km affect the total transport in the West Spitsbergen Current significantly. The Atlantic Water transports range between 2 and 7 Sv, mainly dominated by the cross-sectional area occupied by this water mass. The total northward heat transport across 75°N is estimated as 54.7 TW and across 79°40 0 N as 42 TW in September 1997.