Drivers of subsurface temperature variability in the Northern California Current

The Washington/Oregon shelf, embedded in the Northern California Current System, is a productive habitat with important commercial fisheries. One of the most valuable species is Dungeness crab, which resides on the subsurface shelf and is sensitive to near‐bottom ocean properties such as temperatures and oxygen concentrations. The predictability of these properties on seasonal time scales is being investigated using J‐SCOPE (JISAO's Seasonal Coastal Ocean Prediction of the Ecosystem), developed at the University of Washington’s Cooperative Institute for Climate, Ocean and Ecosystem Studies (CICOES, formerly the Joint Institute for the Study of the Atmosphere and Ocean).

Previous studies have explored the driving mechanisms of surface temperature predictability with a focus on linkages to El Niño–Southern Oscillation (ENSO); this study investigates their counterparts for subsurface temperatures off the Washington/Oregon shelf. We find that  remote (nonlocal) atmospheric and oceanic features ultimately exert a strong influence on the subsurface temperatures. A relatively simple statistical model explains 83% of the subsurface temperature variability. Predictors include ENSO, the PDO (Pacific Decadal Oscillation), the depth of the California Undercurrent, and water mass properties of the North Pacific, each with different time lags. These results on potential sources of predictability are relevant to the continued development of current seasonal forecasting efforts off the U.S. West Coast.

For more information,  view the article at Journal of Geophysical Research: Oceans.