In March 2010, when the vertical mixing was weak, relatively high surface Chl a values, as well as a related peak in diatom fluxes were found at 1003 m. It has been shown that an anticyclonic eddy followed by a cyclonic eddy coming from southwest off Taiwan passed by station SCS-N from February 20th to March 25th (Fig. 6c). In March, station SCS-N was located at the edge of the anticyclonic eddy and close to the cyclonic eddy (Fig. 6c).