The mass accumulation rate (MAR) of organic carbon in the western sector of the western Pacific warm pool (WPWP), a currently high primary productivity region, clearly responded to glacial-interglacial alternations, although oceanic surface temperature fluctuated within a narrow range of 2 ¿C. Wind-related mixing or upwelling would have increased primary productivity during glacial periods when the Asian winter monsoon was more developed. Higher MARs of lithogenic matter generally occurred during relatively low sea level periods. The increased terrestrial inputs would have been linked with the enhanced biological activity in the western sector of the WPWP. In contrast, more intense surface mixing or upwelling driven by stronger winds might have made little or no difference to the low to medium productivity in the central and eastern sectors of the WPWP because a deep thermocline prevented nutrient-bearing water from upwelling even during the glacial times. ¿ 1999 American Geophysical Union