S1: Science Board Symposium (0.75 day)
Beyond the continental slope - complexity and variability in the open North Pacific Ocean
Co-Convenors: R. Ian Perry (SB), Vladimir I. Radchenko (BIO), Yukimasa Ishida (FIS), John E. Stein (MEQ), Kuh Kim (POC), Igor I. Shevchenko (TCODE), and Harold P. Batchelder and Suam Kim (CCCC)
Most of the area of the North Pacific Ocean is in the pelagic realm, beyond the major currents and marginal seas that border the continents. This oceanic region has often been perceived as physically homogeneous and stable with low biological productivity. In reality, it is a spatially and temporally dynamic environment of high complexity. The diversity and structure of open ocean ecosystems are influenced by both horizontal and vertical structure of the ocean's physical and biological properties and by their seasonal cycles. Sharp contrasts in oceanic bottom topography caused by seamounts and islands add additional structure and complexity. In spite of its relatively low primary productivity, the region supports complex ecosystems with high biodiversity, and is home to many endangered species. Marine resources are important to the peoples of the North Pacific and are fished by fleets from many Pacific Rim nations. This session seeks to improve our understanding of the physical, chemical and biological structure and dynamics of North Pacific oceanic waters far beyond the continental shelf, with particular emphasis on the subtropical gyre. The symposium will consider how these complex subtropical oceanic ecosystems are structured and maintained, in light of their generally low productivity. It will provide opportunities to compare and contrast these areas with neighbouring regions of higher productivity. How important are small and meso-scale features, such as fronts and eddies, to the growth, survival and distribution of upper trophic level species? How do ecosystems in the open ocean respond to changes in vertical and horizontal structure? How have sub-tropical waters been affected by recent global changes? What are the major factors causing changes to open ocean ecosystems, particularly in the sub-tropics? What are the physical and biological links between the subtropical gyre and other regions of the North Pacific? What are the human interactions with these systems?