Mesoscale Current Fluctuations Observed in the Deep Western North Pacific

Abstract

A set of simultaneous long-term, deep current measurements was taken using amoored array in the mid-ocean of the western North Pacific near 30°N, 146°E. Five currentmeters at three stations provided good quality records over 84 days. Low-frequency currentfluctuations with meridional dominance are clearly seen in the deep layer records. They areconsistent with signals of a mesoscale current fluctuation which has a period of about 100days, an east-west wave length of about 200 km, and a westward phase propagation with aspeed of about 2cm sec^-1. Bottom intensification of the east component of low-frequencycurrent fluctuations is also observed.