The Ahklun Mountains support the only extant glaciers in western Alaska. The glaciers were originally mapped by the U.S. Geological Survey using photogrammetry methods based on 1972 - 1973 aerial photos. We surveyed for presence or absence of the glaciers by fixed-wing aircraft in 2006. Of 109 glaciers originally mapped, 10 (9%) had disappeared. Using aerial imagery of a subset of 76 glaciers at three time steps between 1957 - 2009, we determined the average rate of areal loss was 45% over 52 years. At this rate, it is likely that all Ahklun Mountain glaciers will be extinguished by the end of the current century.

Ahklun Mountain glacier status in 2009Ahklun Mountain glacier status in 2009, area, and mapping confidence at three time steps for a subset of 76 glaciers.Table A1.docMapping confidence of Ahklun Mountain glacier filesMapping confidence at three time steps for 76 Ahklun Mountain glaciers, southwestern Alaska.Table A2.doc