Distribution of particulate matter in the south-eastern Beaufort Sea in late summer

Abstract

forty-one stations were occupied for measurements of CTD/transmissometer, suspended particulate matter (SPM), chlorophyll-a (Chl-a), and particulate organic carbon (POC) in the southeastern Beaufort Sea in September 1986. Preliminary results indicate that both the Mackenzie River and sediments in the nearshore (about 5 m or less) are two major particulate sources to the surface layer of the inner shelf (estuary). Further, a near-bottom light-attenuating layer was normally observed on the shelf. Compared to the interior Arctic Ocean, water over the Mackenzie Shelf has POC concentrations almost an order of magnitude higher throughout the water column (from surface to 350 m depth). This is probably a result of organic particles added to the surface layer by river input and phyto-plankton production with subsequent settling into deeper water during the open-water season. 1.