TY - JOUR T1 - Hydrologic variation during the last 170,000 years in the southern hemisphere tropics of South America JF - Quaternary Research Y1 - 2004 A1 - Fritz, S. C. A1 - Baker, P. A. A1 - Lowenstein, T. K. A1 - Seltzer, G. O. A1 - Rigsby, C. A. A1 - Dwyer, G. S. A1 - Tapia, P. M. A1 - Arnold, K. K. A1 - Ku, T. L. A1 - Luo, S. D. AB - Despite the hypothesized importance of the tropics in the global climate system, few tropical paleoclimatic records extend to periods earlier than the last glacial maximum (LGM), about 20,000 years before present. We present a well-dated 170,000-year time series of hydrologic variation from the southern hemisphere tropics of South America that extends from modem times through most of the penultimate glacial period. Alternating mud and salt units in a core from Salar de Uyuni, Bolivia reflect alternations between wet and dry periods. The most striking feature of the sequence is that the duration of paleolakes increased in the late Quaternary. This change may reflect increased precipitation, geomorphic or tectonic processes that affected basin hydrology, or some combination of both. The dominance of salt between 170,000 and 140,000 yr ago indicates that much of the penultimate glacial period was dry, in contrast to wet conditions in the LGM. Our analyses also suggest that the relative influence of insolation forcing on regional moisture budgets may have been stronger during the past 50,000 years than in earlier times. (C) 2003 University of Washington. All rights reserved. VL - 61 IS - 1 N1 - 776jhTimes Cited:98Cited References Count:43 JO - Hydrologic variation during the last 170,000 years in the southern hemisphere tropics of South America ER - TY - CHAP T1 - Ostracoda and paleoceanography T2 - American Geophysical Union Monograph - The Ostracoda: Applications in Quaternay Research Y1 - 2002 A1 - Cronin, T. M. A1 - Boomer, I. A1 - Dwyer, G. S. A1 - Rodriguez-Lazaro, J. ED - Holmes, J. A. JF - American Geophysical Union Monograph - The Ostracoda: Applications in Quaternay Research N1 - id: 1473 ER - TY - JOUR T1 - A 160,000-year record of tropical climate variability from Salar de Uyuni, Bolivia JF - EOS, Transactions, American Geophysical Union Y1 - 2001 A1 - Fritz, S. C. A1 - Baker, P. A. A1 - Dwyer, G. S. VL - 80 N1 - id: 1474 ER - TY - JOUR T1 - Climatic significance of large lakes on the Altiplano of South America JF - EOS, Transactions, American Geophysical Union Y1 - 2001 A1 - Baker, P. A. A1 - Seltzer, G. O. A1 - Fritz, S. C. A1 - Rigsby, C. A. A1 - Dwyer, G. S. VL - 82 N1 - id: 333 JO - Climatic significance of large lakes on the Altiplano of South America ER - TY - JOUR T1 - Ostracode Mg/Ca ratios suggest warmer-than-present early and middle Holocene in the western Arctic Ocean JF - EOS, Transactions, American Geophysical Union Y1 - 2000 A1 - Dwyer, G. S. VL - 81 IS - 4 N1 - id: 1475 ER -