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The Demise of the Little Ice Age in Chile
Harrison, S. and Winchester, V.  2000.  Nineteenth- and twentieth-century glacier fluctuations and climatic implications in the Arco and Colonia Valleys, Hielo Patagonico Norte, Chile.  Arctic, Antarctic, and Alpine Research 32: 55-63.

In an attempt to rewrite climatic history, a small band of climatologists is suggesting that the Little Ice Age and Medieval Warm Period were neither real nor global phenomena, in order to make the putative warming of the last part of the 20th century appear highly unusual, which characteristic they equate with anthropogenic-induced, which attribution they associate with the historical rise in the air's CO2 content, which then gives them a reason to call for dramatic reductions in the use of fossil fuels, which we believe to be unwarranted.  Hence, it is important to demonstrate that the Little Ice Age and Medieval Warm Period were truly global events, as this study helps to do for the Little Ice Age.

What was done
The authors employed dendrochronology, lichenometry and aerial photography to date the 19th- and 20th-century fluctuations of the Arco, Colonia and Arenales glaciers on the eastern side of the Hielo Patagonico Norte in southern Chile.

What was learned
It was determined that these and four other glaciers on the western side of the ice field began to retreat "from their Little Ice Age maximum positions" somewhere between 1850 and 1880, and that this trend continued "through the first half of the 20th century with various still-stands and oscillations between 1925 and 1960 ... with retreat increasing since the 1960s."

What it means
Even as far away from the lands surrounding the North Atlantic as southern Chile, the Little Ice Age is evident in a variety of proxy climate records.  In addition, the period of its demise appears to be the same as it was in the Northern Hemisphere.  This observation constitutes one more stake to be driven into the heart of the ill-advised movement that is trying to convince the world that this global climatic event never occurred.  We hope death comes quickly to this rogue hypothesis.

Reviewed 13 December 2000