University of Cincinnati, Cincinnati, OH, United States

Combined glacial geologic and palynologic data from the southern Lake District, Seno Reloncavi, and Isla Grande de Chiloe in middle latitudes (40 degrees 35'-42 degrees 25'S) of the Southern Hemisphere Andes suggest (1) that full-glacial or near-full-glacial climate conditions persisted from about 29,400 to 14,550 (super 14) C yr BP in late Llanquihue time, (2) that within this late Llanquihue interval mean summer temperature was depressed 6 degrees -8 degrees C compared to modern values during major glacier advances into the outer moraine belt at 29,400,26,760, 22,295-22,570, and 14,550-14,805 (super 14) C yr BP, (3) that summer temperature depression was as great during early Llanquihue as during late Llanquihue time, (4) that climate deteriorated from warmer conditions during the early part to colder conditions during the later part of middle Llanquihue time, (5) that superimposed on long-term climate deterioration are Gramineae peaks on Isla Grande de Chiloe that represent cooling at 44,520-47,110 (super 14) C yr BP (T-11), 32,105-35,764 (super 14) C yr BP (T-9), 24,895-26,019 (super 14) C yr BP (T-7), 21,430-22,774 (super 14) C yr BP (T-5), and 13,040-15,200 (super 14) C yr BP (T-3),(6) that the initial phase of the glacial/interglacial transition of the last termination involved at least two major steps, one beginning at 14,600 (super 14) C yr BP and another at 12,700-13,000 (super 14) C yr BP, and (7) that a late-glacial climate reversal of < or =2-3 degrees C set in close to 12,200 (super 14) C yr BP, after an interval of near-interglacial warmth, and continued into Younger Dryas time.