Enhanced Chlorophyll Concentrations Induced by Kuroshio Intrusion Fronts in the Northern South China Sea

New evidences were provided that Kuroshio intrusion in winter is able to increase phytoplankton growth in the open ocean of the northern South China Sea (SCS) based on multiple data sources. Strong fronts due to Kuroshio intrusion and interactions with the SCS water are associated with intense upwelling, supplying high nutrients from the subsurface SCS water and increasing phytoplankton productivity in the frontal region. High chlorophyll is more dynamically related to these fronts than to the alongshore wind, wind stress curl, and eddy kinetic energy on interannual time scale. Further examinations suggest that fronts associated with Kuroshio intrusion into the SCS are linked with large‐scale climate variability. During El Niño years, stronger Kuroshio intrusion results in stronger fronts that generate intensified local upwelling and enhanced Luzon winter blooms. Key Points Kuroshio intrusion is able to increase the phytoplankton chlorophyll in the open ocean of the northern South China Sea Fronts induced by the interaction between Kuroshio intrusion and the South China Sea water can generate local upwelling and enhanced productivity On interannual time scale, Kuroshio intrusion, local fronts, and high chlorophyll patches are dynamically linked