Response Of The Sunda Slope Environment To The High Latitudes Climate Events And Global Sea-level Changes Since The Last Glacial Maximum

Variations in tropical sea surface environment patterns and the phasing relative toclimate change in higher latitudes provide insight into the mechanisms of rapidclimate change on both millennial and centennial time-scales. Here, change in the seasurface temperature(SST) and salinity(SSS) over the last24ka have been estimatedfrom sediment core CG2recovered from the the Sunda slope by means of Mg/Ca ratioand oxygen isotopes on the planktonic foraminifera Globigerinoides ruber, combinedwith the statistical data of grain size and planktonic foraminifera.Our results imply that sea surface salinity, abundance of warm-water species,grain size and depth of thermocline display obvious responses to the rapid climatechange. During the periods of H1, YD,8.2ka cooling events, the ocean conditionsshows increased SSS, shoaled thermocline, increased sand and silt percentage,decreasded abundance of warm-warter species and clay percentage. While, during theB/A warm period and the late YD event, data shows opposite. Compared with theslowly deglacial warming of the open Pacific, the SST record in southwestern SCSshows a deglacial warming interrupted by a cooling event coeval with H1event andreached about1.5℃, followed by marked B lling and late YD SST increasing, whichshows a Greenland type‘deglacial warming. We suggest that their difference may liesin the SCS is more strongly affected by East Asian monsoon. The Latitudinal movingof ITCZ causes rapid changing of the East Asian monsoon which drived the timing and phasing of the rapid climate change coeval with the higher latitudes. The SSS ofthe southwestern SCS during the LGM was lower1.15‰than present is interpretedto an higher freshwater contribution due to a greater proximity o f the core site to theNorth Sunda River at that time. Several short-term shifts towards higher and lowerSSS change that are likely related to sea level and abrupt changes in the intensity ofthe East Asian summer monsoom. It is worth mentioning that Holocene oscillations inthe EASM centered around periodicities of660years. The eastern and westernequatorial Pacific salinity variations were almost the same during the rapid climatechange events. The variability of upper water environment of the western tropicalPacific were closely linked with latitudinal shifts of the intertropical convergencezone (ITCZ) and its related East Asian monsoon anomaly since the LGM.