Ocean Science www.ocean-sci.net 1812-0784 1812-0792 6 2 2010 10.5194/os-6-539-2010 http://www.ocean-sci.net/6/539/2010/ http://www.ocean-sci.net/6/539/2010/os-6-539-2010.html http://www.ocean-sci.net/6/539/2010/os-6-539-2010.pdf 539 548 2010-06-04 The role of continental shelves in nitrogen and carbon cycling: Northwestern North Atlantic case study K. Fennel katja.fennel@dal.ca Dalhousie University, Department of Oceanography, Halifax, Canada Continental shelves play a key role in the cycling of nitrogen and carbon. Here the physical transport and biogeochemical transformation processes affecting the fluxes into and out of continental shelf systems are reviewed, and their role in the global cycling of both elements is discussed. Uncertainties in the magnitude of organic and inorganic matter exchange between shelves and the open ocean is a major source of uncertainty in observation-based estimates of nitrogen and carbon fluxes. 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