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Another Little Ice Age Fingerprint From Chile
Reference
Bertrand, S., Boës, X., Castiaux, J., Charlet, F., Urrutia, R., Espinoza, C., Lepoint, G., Charlier, B. and Fagel, N.  2005.  Temporal evolution of sediment supply in Lago Puyehue (Southern Chile) during the last 600 yr and its climatic significance.  Quaternary Research 64: 163-175.

What was done
In another article recently reviewed on our website, Koch and Kilian (2005) studied the moraines of several Chilean glaciers, documenting their advance during the global chill of the Little Ice Age.  In the present study, Bertrand et al. reveal yet another fingerprint of this cold-earth episode in this region by examining a 600-yr proxy precipitation record obtained from a sediment core retrieved from Lago Puyehue, Chile (40.70°S, 72.45°W).

What was learned
The results of the authors' analysis revealed the presence of a wet climate between AD 1490 and 1700 followed by drier conditions until about 1900.  In addition, the wet and dry periods were shown to correspond with other paleoclimate records of the region.  The wetter period, for example, was "strikingly consistent" with higher ice accumulation rates in the Quelccaya ice core of Peru (Thompson et al., 1985); and it corresponded with colder temperatures deduced from tree rings in Northern Patagonia (Luckman and Villalba, 2001), while the drier time period was similar to that reported by Lara and Villalba (1993).

What it means
What is the significance of these results?  According to Bertrand et al., the 1490-1700 wet period "is associated with the onset of the European Little Ice Age (LIA) and interpreted as its local signature," which they say "supports the fact that the LIA was a global event, not only restricted to the Northern Hemisphere."  We agree.

References
Koch, J. and Kilian, R.  2005.  "Little Ice Age" glacier fluctuations, Gran Campo Nevado, southernmost Chile.  The Holocene 15: 20-28.

Lara, A. and Villalba, R.  1993.  A 3620-year temperature record from Fitzroya cupressoides tree rings in Southern South America.  Science 260: 1104-1106.

Luckman, B.H. and Villalba, R.  2001.  Assessing the synchroneity of glacier fluctuations in the western cordillera of the Americas during the last millennium.  In: Markgraf, V. (Ed.), Interhemispheric Climate Linkages, San Diego, California, USA, pp. 119-140.

Thompson, L.G., Mosley-Thompson, E., Bolzan, J.F. and Koci, B.R.  1985.  A 1500-year record of tropical precipitation in ice cores from the Quelccaya ice cap, Peru.  Science 229: 971-973.

Reviewed 15 February 2006