In order to better understand the sources, sinks and hydrodynamic/biogeochemical influences on particulate matter distribution and variability in Arctic basins, we combined data from two 2015 fall expeditions: one from Bering Strait (USCGC Healy) and the other from Barents Sea (R/V Polarstern) meeting at the North Pole. Sections of beam attenuation due to particles were overlain by salinity, temperature, and chlorophyll-a fluorescence (Chl-a), and with nitrate contours on Chl-a sections to compare with concentrations of particulate matter (PM) and particulate organic carbon (POC) from full water column filtered samples. Dense Pacific water moving swiftly through Bering Strait erodes and carries sediment-laden waters onto the Chukchi Shelf, much of it moving in and above Barrow Canyon or is entrained in eddies. This nutrient-rich Pacific water sinks below the low-salinity, nutrient-poor polar mixed layer, forming a thick lens of high salinity water known as Pacific halocline waters. The nutrient-poor mixed layer inhibits photosynthesis in surface waters of Canada and Makarov Basins, but subsurface Chl-a maxima are observed when nutrients are available. Surface-water POC biomass appears greater in Barents Sea than in Beaufort Sea because nutrient-rich Atlantic water entering Barents Sea is not isolated from surface waters by strong stratification. Surface water freezes, creating high-density water that cascades into 400 m basins in Barents Sea and into deep Nansen Basin, eroding sediment that forms patches of nepheloid layers in the shallow basins. Nepheloid layers in the deep basins are very weak, consistent with a lack of strong currents there.