Glacier Variability in the Wind River Range, Wyoming

Variability in surface area for 44 glaciers in Wyoming's Wind River Range was estimated through a comparison of historic aerial photography from 1966 to 2006. The total surface area of the 44 glaciers was estimated to be 45: 9 +/- 1: 6 km(2) in 1966 and 28: 6 +/- 0: 4 km(2) in 2006, a decrease of 38%. Glacial surface area was also estimated utilizing resampled aerial photography to assess the relationship between area and measurement scale. Aerial photographs were resampled to resolutions of 10 m, 15 m, 22.5 m, and 30 m to represent other satellite image resolutions used for evaluating glacier boundaries. The results show a linear decrease of total glacier area as resolution decreases. When comparing 1-m resolution to the resampled 30-m resolution for 1966 and 2006 photos, an average area difference of 5% was observed. Additionally, the current research was compared to previous research efforts that utilized Landsat imagery to detect glacier area change from 1985 to 2005. We concluded that fine spatial resolution remotely sensed imagery remains the preferred and most accurate source for measuring glacier characteristics. DOI: 10.1061/(ASCE)HE.1943-5584.0000384. (C) 2011 American Society of Civil Engineers.