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Growing evidence suggests that the low atmospheric CO2 concentration of the ice ages resulted from enhanced storage of CO2 in the ocean interior,largely as a result of changes in the Southern Ocean.Early in the most recent deglaciation,a reduction in North Atlantic overturning circulation seems to have driven CO2 release from the Southern Ocean,but the mechanism connecting the North Atlantic and the Southern Ocean remains unclear.Biogenic opal export in the low-latitude ocean relies on silicate from the underlying thermocline,the concentration of which is affected by the circulation of the ocean interior.Here we report a record of biogenic opal export from Polar Antarctic Zone that shows pronounced opal maxima during each glacial termination over the past 638 ka, corresponding to the opal peaks of North Atlantic ODP 658.These opal peaks are consistent with a strong deglacial reduction in the formation of silicate-poor glacial North Atlantic intermediate water(GNAIW).We interpret the opal peaks in north Atlantic and PAZ as resulting from the enhanced Southern Ocean upwelling and the ratio of silicate-rich AABW in the intensive mixed upwelling.We argue that this is a more pausible senario than a mixing of silicate-rich abyssal waters into the low latitude Atlantic thermocline.