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The Little Ice Age on the Andean Altiplano
Valero-Garces, B.L., Delgado-Huertas, A., Navas, A., Edwards, L., Schwalb, A. and Ratto, N. 2003. Patterns of regional hydrological variability in central-southern Altiplano (18-26S) lakes during the last 500 years. Palaeogeography, Palaeoclimatology, Palaeoecology 194: 319-338.

What was done
The authors describe the paleohydrological evolution of three high-altitude (ca. 4000 m above sea level) Altiplano lakes located in a transect including northern Chile (Lago Chungara, 18S), the Atacama Altiplano (Laguna Miscanti, 23S) and the northwestern Argentinean Puna (Laguna El Peinado, 26S), based on sedimentological, geochemical and isotopic analyses of sediment cores.

What was learned
The authors report that "coeval to the termination of the LIA [Little Ice Age]" a change to modern conditions occurred in the late 19th century in all of the records, following on the heels of a previous drier LIA period that exhibited "different patterns of timing, duration, and intensity." They also note that "other high-resolution records from the region (ice caps, historical documents, dendrochronological and lake records) show abrupt paleohydrological and paleoclimatic changes synchronous to the onset and termination of the LIA."

What it means
"Although there exist local differences and dating uncertainties," in the words of the authors, "the LIA stands out as a significant though complex climatic event in the Andean Altiplano," once again providing evidence for the global expression of this most recent cool phase of the millennial-scale cycling of climate that extends through glacial and interglacial periods alike.

Reviewed 17 September 2003