Based on analyses of δ18O, AMS14C ages, grain-size distribution of standard deviation stages and relative abundance of Globigerina bulloides which commonly encountered in upwelling areas, as well as the record of clay mineral in Gingele et al. (2002), the authors come to the following conclusion: during the last glacial period 30~17 ka B.P., when sea level was lower, terrigenous sands supply increased. Even the austral summer insulations strengthened, though the southward shift of the ITCZ in the austral summer may have been considerably restricted, where the northwest monsoon did not operate, and this would create a situation analogous to the southeast monsoon operating throughout the year, because the trade winds would blow continually across the study area. The climate was cold and dry.