In situ deep water particle sampler and real-time sensor package with data from the Madeira Abyssal Plain

Abstract

A deep water particle sampler was designed to measure physical variables in real time and collect particulate and water samples in situ with the view to furthering our understanding of biogeochemical cycles. Profiles of particulate concentration, particle size distribution (10–200 μm) and temperature against depth are taken on the outward and return casts to a maximum depth of 6000 m. Particle samples are collected by large volume filtration at four depths preselected on the basis of outward cast data. For metal analyses, 1 μm polycarbonate membranes are used, and glass fibre filters for organic analysis; larger particles may be collected by prefilters of any chosen mesh size. Data presented from the Madeira Abyssal Plain illustrate the function of the instrument and the results are compared to those reported previously.