Marine snow is important in the vertical flux of marine particulate matter. Asper will design and construct three complimentary camera systems to study the abundance, flux and in situ sinking speed of marine snow aggregates. The first system will photograph a well-defined volume of water for assessment of the concentration of these aggregates either along a vertical profile or through time on a stationary or floating mooring. The second and third cameras are mounted normal to (side-looking) and beneath (upward-looking) a transparent settling chamber/sediment trap. The side-looking camera will determine the sinking speed of aggregates within the settling chamber by observing their fall over a specified time interval. The third camera will measure the flux of aggregates by observing their successive arrivals on the clear bottom of the trap. Material collected by the trap will also be compared to the images of aggregate arrivals for estimation of the composition and mass flux contribution of these aggregates. Combining these measurements will allow accurate determination and modeling of the role of these aggregates in the vertical flux of particulate matter in any oceanic water column.
