ABSTRACT: The role of climatic variation in regulating marine populations and communities is not well understood, but generally conceded to be important. To achieve greater understanding and to help us isolate the influence of natural variability from anthropogenic, the sign, amplitude and frequency of both climatic and biotic variations should be compared as a necessary first step. Here we use sea surface temperature and sea level pressure anomalies as measures of climate-ocean variability. There have been large, interannual, warm/cold sea surface temperature anomalies off the west coast of the United States during the past 80 years. These appear rather suddenly, last for months to years and disappear rather suddenly along many hundreds of miles of coastline. The warming/cooling does not appear to originate in the south or north but, rather, in most cases, synchronously along the entire coastline. The frequency of warm events has increased since 1977 leading to an interdecadal shift in mean sea surface temperature. These nearshore anomalies are well correlated, at low frequencies with those of much of the entire North Pacific Basin including the Gulf of Alaska. Although spatially extensive, serial, biological observations are often incomplete, we can show that the large scale abundance of zooplankton, pelagic fishes, and oceanic sea birds, in the California Current, have been greatly depressed and that nearshore kelp forests were disturbed, during these anomalous events. We emphasize two frequencies, the interannual (El Niños) and the interdecadal (Regime Shifts) because of their large amplitude and spatial scale, involving the entire California Current and Gulf of Alaska. The nature of the proposed mechanisms linking biology and physics differs between interannual and interdecadal frequencies and between the California Current and Gulf of Alaska.