Preface / Deep-Sea Research II, Volume 45 (1998)

Abstract

Ecosystems of the eastern boundary regions of the ocean basins, like those off California, Northwest Africa and Peru, are known for enhanced primary production and resulting large clupeid fisheries. In these eastern boundary regions, the basin-scale circulation brings the thermocline, pycnocline and nutricline close to the surface and often in contact with the mixed layer. Processes such as coastal upwelling then act to bring these cool and nutrient-rich waters to the surface. Photosynthesis is stimulated by the enhanced nutrient supply to sunlit waters, and food for supporting the ecosystem is generated. The source and fate of this primary production is variable, reflecting the dynamic physical character of eastern boundary systems. The physical and biological variability are most notable on mesoscale or subseasonal (upwelling events, jets and eddies), seasonal (spring transition, upwelling, winter) and interannual (El Nifio) scales. Decadal and interdecadal oscillations are evident in the longer time series (Hayward, 1996; Ingraham Jr. et al., 1998) and the analysis of White et al. (1997) suggests that the Northeast Pacific, and the California Coast in particular, are regions of higher than average decadal and interdecadal variability. And of course, the shadow of global warming looms on the horizon, if not already underway. Considering these factors, and the planning and implementation of major multi-disciplinary programs along the West Coast of North America (GLOBEC, CoOP), we have assembled a series of papers dealing with the oceanography of California waters into a volume of Deep Sea Research II.