Mesoscale eddies in the Mindanao Dome region

The characteristics and generation mechanism of eddies in the Mindanao Dome region are studied. Most eddies in this region are nonlinear, less than 300 km in diameter and have lifespans less than 90 days. Eddies are mostly locally born because topography blocks eddies from the east and eddies from the south cannot cross the equator. Both barotropic and baroclinic instabilities are responsible for eddy generation. Barotropic instability is active and dominant near the surface due to the strong horizontal shear of the North Equatorial Counter Current, whereas baroclinic instability caused by a horizontal density gradient is important in the thermocline.