Surface currents in the Northwestern Pacific Ocean observed by surface drifting buoys: A case study

Abstract

Twenty six surface drifting buoys were deployed in the area 5~7°N on 165°E in June of 2014 as the MOF/Korea-NOAA JPA project and the Global Drifters Program. The drifter trajectories for one year reveal the general features of the surface circulation in the northwestern Pacific Ocean, e.g., the North Equatorial Current (NEC), the separation of the NEC into the Kuroshio and Mindanao Current (MC), the retroflection of the MC, the Kuroshio intrusion into the South and East China Seas etc. The NEC separation location was around 13°N in March and April of 2015. The fastest drifter velocity appeared in the North Equatorial Countercurrent with its estimated value of about 2 kn in June and July of 2015. Consecutive small circular structures indicating inertial motion and mesoscale eddies were observed mainly in the northern part of the NEC and the western Philippine Sea, respectively.