NOAA/WDS Paleoclimatology - Wang et al. 2007 Botuverá Cave 90KYr Stable Isotope Data

A U-Th dated 90,000 year-long speleothem oxygen isotope record from southern Brazil anti-correlates remarkably with the cave calcite records from eastern China, but positively correlates with the speleothem record from northeastern Brazil, suggesting an interhemispheric anti-phasing of rainfall on both millennial and orbital timescales, likely related to displacement in the mean position of the intertropical convergence zone and associated asymmetry in Hadley circulation. The phase relationships among these records are consistent with the hypothesis that abrupt climate events during the last glacial period are triggered by oceanic circulation changes in the high latitudes and enhanced by tropical feedbacks.