Cabled observing systems will provide an unprecedented opportunity to measure ocean processes across a broad continuum of temporal and spatial scales. Water column measurements will address questions related to ocean turbulence and dynamics, the role of the ocean in global climate, and non-equilibrium ecosystem dynamics. The emphasis is on interdisciplinary observations of water-column processes offshore (in this case) of the continental margin, a region forced by basin-scale atmosphere and ocean phenomena, variations in the North Pacific circulation, air-sea interactions, and shelf-slope interactions with the deep sea.

The West Wind Drift

The northeast Pacific exhibits a range of oceanographic features spanning multiple spatial and temporal scales. The West Wind Drift (WWD) is a major eastward wind-driven current that forms the boundary between the North Pacific subtropical gyre and subarctic gyre, each having fundamentally different physical, biological, and biogeochemical characteristics. The position of the boundary front between the gyres migrates seasonally north and south about 1000 km and may vary substantially during El Niño/Southern Oscillation (ENSO) events with considerable eddy and meander activity.

The WWD bifurcates within the region to produce the Alaska Current flowing north and the California Current flowing south along the eastern boundary of the North Pacific. This boundary region is characterized by frequent strong winter storms, seasonal wind reversals, moderate upwelling in spring and summer, significant freshwater runoff, strongly seasonal primary and secondary production, and patchy spawning by fish.

Basin-scale climate phenomena, such as ENSO and the Pacific Decadal Oscillation (PDO) influence ocean processes in the northeast Pacific on time scales ranging from days to decades. Interannual to decadal variability in the magnitude of the WWD and the position of its bifurcation should result in coupled variations in volume transports of the California and Alaska Currents.

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