Middle Pleistocene sea-surface temperature change in the southwest PacificOcean on orbital and suborbital time scales

A record of estimated sea surface temperature (SST) change between 575 and 400 ha has been obtained from planktonic foraminifera at Deep Sea Drilling Project Site 594 in the southwest Pacific Ocean. The Site 594 record indica tes that SSTs during marine oxygen isotope stage 11 were similar to those o f the Holocene, in contrast to suggestions of warmer than Holocene SSTs dur ing stage 11, If these SSTs reflect global conditions, then ice-sheet colla pse may not require temperatures warmer than in the Holocene. Millennial-sc ale oscillations in SST (similar to 3 degrees C) occurred within the stage 12 glacial interval, spaced every similar to 5-10 k.y., on time scales simi lar to those observed within stage 12 in the North Atlantic The consistency between these records may require global-scale mechanisms capable of produ cing rapid climate change, as suggested for later Quaternary intervals.