Historical fluctuations of the Gualas and Reicher Glaciers, North Patagonian Icefield, Chile.

Dendrochronology was used to date historical fluctuations of the little-visited Gualas and Reicher Glaciers on the North Patagonian Icefield in southern Chile. Vegetation trimlines dating to ad 1876, 1909 and 1954 show that glacier downwasting and retreat mirrored the patterns found at the neighbouring San Rafael and San Quintin Glaciers. Intermediate stages of recession of the Gualas and Reicher Glaciers dating to the early 1920s, mid-1930s and 1960s are also reflected by similar stages in the San Rafael and San Quintin Glaciers. We propose that the common responses shown by these four glaciers argue for climatic control of their movements and that glacier dynamics in this region are principally controlled by changes in precipitation rather than temperature since annual mean temperatures at Cabo Raper, the nearest meteorological station, have shown no trend since the early 1940s whereas precipitation, peaking in the winter months, has varied widely since the 1920s. [ABSTRACT FROM AUTHOR]