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Based on new Be-10 data for moraines in the Cordillera Blanca of central Peru, we have calculated model ages of three sets of Pleistocene glacial moraines. In order of decreasing age, these are the Cojup, Rurec and Laguna Baja moraines, The oldest moraines occur at the lowest elevations and yield dates of >400ka pre-dating the last interglacial and demonstrating that maximum ice volumes Occurred during previous glacial periods, and not at the end of the last glacial. Our new data from the Younger moraines indicate that the end of the last glacial cycle comprised two separate advances at ca. 29 ka and ca. 16.5 ka, each reflecting significant (>4 degrees C) tropical of cooling at 10 degrees S. These data combined with Published records from the Laurentide ice sheet, indicate that climate instabilities associated with the close of the last glacial were likely global and Synchronous in nature. Copyright (C) 2005 John Wiley & Sons, Ltd.