Linkages Between the Carbon Cycle and Biota in the Global Ocean

Ocean biogeochemistry and physics are fundamental in shaping the composition and productivity of marine fisheries.  Integrating the effects of various physical and chemical processes which influence the production and structure of the planktonic community is challenging, especially when considering changes resulting from anthropogenic emissions of greenhouse gases.  Utilization of global “earth system” models allows comprehensive assessment of the atmospheric, hydrographic, and biogeochemical processes affecting productivity in the context of global change.  Such models allow us to examine qualitative hypotheses concerning future change in a more quantitative fashion.  Here, I explore the results of earth system models and describe biogeochemical changes that are expected to influence future fisheries production by altering the base of the marine food web, changing the intensity of oxygen minimum zones, and reducing the ocean’s pH.  One key finding of this work is recognition that the statistical relationships based on historical observations of the marine environment may be inadequate to predict changes which will occur as a result of global climate change.  These differences between historical and future physical-biological relationships are particularly evident in eastern boundary current upwelling systems—regions which are invaluable to the world’s fisheries.  Understanding the mechanisms through which climate change will alter the production and flux of organic matter to higher trophic levels is central step in projecting the future of marine fisheries.