Program

Little is known on how the particle export temporally evolved with the physical dynamics within the cyclonic eddies due to a lack of field observation. This study investigates all the cyclonic eddies that passed the Hawaii Ocean Time Series (HOT) station during 1989-2014, and the export records in sediment trap are available for 25 of the compiled eddies. Those field observations of the particle export were carried out under very different evolutional timing after tracking the temporal variation of the sea level anomaly of each eddy. Different response of carbon and silica fluxes to the eddy evolutional stage is observed in those eddies. It seems that carbon export is enhanced earlier and broken down faster than silica export which is usually elevated in eddy’s late stage. In addition, the amplitude of the silica enhancement in the eddies (compared to the non-eddy region) is found to be greater than that of carbon. It thus confirms that cyclonic eddies might act as silica export favorable system (instead of carbon export favorable system). Further exploration of mechanism on the control of such carbon and silica decoupling will be needed.