Interdecadal Variability

### Interdecadal Variability in Biological Responses

What is the nature of the biological response in Eastern Boundary Currents to demonstrated, basin-scale, interdecadal changes in ocean-atmosphere coupling?

- Are there rapid shifts between well-defined, quasi steady-state bio-physical regimes on time scales of decades to centuries or is there a more continuous progression of ecosystem structure?

- How do the different Regions (I-IV) of the CCS respond-similarly or differently-to these interdecadal shifts?

Among the uncertainties encompassed in these questions are: Do interdecadal shifts in climate lead to modification in timing or intensity of mesoscale activity which affects recruitment, retention/transport, predator-prey relationships, or life history strategies of plankton, nekton and benthic species? Are interdecadal shifts triggered by ENSO activity? How would a sustained (centennial-scale) global warming trend interact with natural interdecadal-scale ecosystem variability in the EBCs?