By mapping the distributions of the geostrophic flow and various water properties on the surface where thermosteric anomaly equals 240 × 10-8 m3 kg-1 (σt 25.60 kg m-3), the circulation in the upper layer of the Pacific Ocean has been studied with emphasis on the subtropical anticyclonic gyres in both hemispheres. The North Pacific shows a double-cell subtropical circulation pattern with the poleward cell along about 30N and the equatorward cell along 20-25N, both extending eastward from the western boundary, where the two cells are joined together....