Oceanography The Official Magazine of
The Oceanography Society
Volume 26 Issue 03

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Volume 26, No. 3
Pages 210 - 219

Ecological Transitions in a Coastal Upwelling Ecosystem

Mark D. Ohman | Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA, USA
Katherine Barbeau | Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA, USA
Peter J.S. Franks | Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA, USA
Ralf Goericke | Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA, USA
Michael R. Landry | Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA, USA
Arthur J. Miller | Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA, USA

Article Abstract

The southern California Current Ecosystem (CCE) is a dynamic eastern boundary current ecosystem that is forced by ocean-atmosphere variability on interannual, multidecadal, and long-term secular time scales. Recent evidence suggests that apparent abrupt transitions in ecosystem conditions reflect linear tracking of the physical environment rather than oscillations between alternative preferred states. A space-for-time exchange is one approach that permits use of natural spatial variability in the CCE to develop a mechanistic understanding needed to project future temporal changes. The role of (sub)mesoscale frontal systems in altering rates of nutrient transport, primary and secondary production, export fluxes, and the rates of encounters between predators and prey is an issue central to this pelagic ecosystem and its future trajectory because the occurrence of such frontal features is increasing.


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