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The sediment core DGKS9603 collected fromthe Okinawa Trough was used as research target. By use ofunsaturated index U_(37)~k of long-chain alkenone, δ~(13)C ofPOC and of planktonic foraminifera (G. sacculifer), the evo-lutions of sea surface temperature and partial pressure ofcarbon dioxide in the atmosphere during the Holocene werereconstructed in the Okinawa Trough. And in combination ofδ~(18)O of planktonic foraminifera, the relative difference of seasurface salinity during the Holocene was also reconstructed.Consequently, three cooling events (E_1-E_3) were identified,each of which occurred at 1.7-1.6, 5.1-4.8 and 8.1-7.4kaBP (call, respectively. Of the three events, E_2 and E_3 areglobally comparable, their occurrence mechanism would bethat the main stream of the Kuroshio Current shifted east-ward due to the enhanced circulation of the northeasternPacific Ocean, which was driven in turn by amplified inten-sity of sunshine and subsequent enhancement of subtropicalhigh pressure: E_1 corresponds to the Small Ice-Age Eventoccurring between 1550 and 1850AD in China. In the Oki-nawa Trough, E_1 might be also related to the eastward shiftof main stream of the Kuroshio current driven by powerfulAsia winter monsoon.
The sediment core DGKS9603 was collected from the Okinawa Trough was used as a research target. By use ofunsaturated index U_ (37) ~ k of long-chain alkenone, δ ~ (13) C of POC and of planktonic foraminifera (G. sacculifer) lutions of sea surface temperature and partial pressure of carbon dioxide in the atmosphere during the Holocene werereconstructed in the Okinawa Trough. And in combination ofδ ~ (18) O of planktonic foraminifera, the relative difference of seasurface salinity during the Holocene was also reconstructed. Conclusion, Three cooling events (E_1 -E_3) were identified, each of which occurred at 1.7-1.6, 5.1-4.8 and 8.1-7.4 kaBP (call, respectively. Of the three events, E_2 and E_3 areglobally comparable, their occurrence mechanism would bethat the main stream of the Kuroshio Current shifted east-ward due to the enhanced circulation of the northeastern Pacific Ocean, which was driven in turn by amplified inten-sity of sunshine and subsequent enhancement of subtropical high pressure: E _1 corresponds to the Small Ice-Age Eventoccurring between 1550 and 1850AD in China. In the Oki-nawa Trough, E_1 might be also related to the eastward shift of the main stream of the Kuroshio current driven by a powerfulAsia winter monsoon.