Glaciología

Glaciares de Chile

Antártica

"Long-term glacier variations in the Central Andes of Argentina and Chile, inferred from historical records and tree-ring reconstructed precipitation"

Le Quesne C., C. Acuña, J. Boninsegna, A. Rivera, & J. Barichivich (2009) : «Long-term glacier variations in the Central Andes of Argentina and Chile, inferred from historical records and tree-ring reconstructed precipitation» Palaeogeography, Palaeoclimatology, Palaeoecology, 281, 334 – 344.

Resumen / Abstract.

Snow and ice in the Central Andes of Chile and Argentina (33–36 °S) are the major source of water for the highly populated regions near the cities of Santiago and Mendoza. However, our knowledge of the forces driving the general glacier retreat in the region is limited. In order to obtain a long-term perspective of glacier fluctuations and their relationships with climate in the Central Andes, historical glacier variations were documented and compared with a tree-ring precipitation reconstruction based upon Austrocedrus chilensis trees. A multi-proxy approach (historical documents, old aerial photographs and satellite imagery) was used to map the fluctuations of eight glaciers, including the Cipreses Glacier, which provides the oldest record of glacier variations in the region starting in AD 1842. All the studied glaciers exhibited a negative trend during the 20th century with mean frontal retreats between −50 and −9my−1, thinning rates between 0.76 and 0.56my−1and a mean ice area reduction of 3% since 1955. More than 350 tree-ring cores were combined into three treering chronologies, which strongly correlate with the instrumental precipitation in Santiago de Chile (33°26′ S;70°41′ W, 520 m asl). Based on these records, a 712-year precipitation reconstruction was developed.

 

(descarga)