Anomalous winter winds decrease 2014 transition zone productivity in the NE Pacific

Abstract

Wind-driven transport from the North Pacific in winter provides nutrients to a highly productive region in the transition zone between the subarctic and subtropics. This region supports many species of fish, marine mammals, and seabirds. In winter 2013/2014, anomalous winds from the south weakened nutrient transport in the eastern North Pacific, resulting in substantial decreases in phytoplankton biomass. By January 2014, waters were warmer than usual by 3.5°C at the center of an affected area covering ∼1.5 × 106 km2. South of this area, winter chlorophyll levels dropped to the lowest levels seen since the Sea-viewing Wide Field-of-view Sensor satellite began taking measurements in 1997. It is anticipated that impacts will be felt in some fisheries and among migrating predators this coming year.