The Fedchenko glacier system harbors the longest glacier (77 km) outside of the polar areas. It has a great influence on the local economy and ecology as a water resource. The glacier area in the Fedchenko basin was investigated using Landsat TM images in 1992, Landsat ETM images in 2000, and ALOS/AVNIR2 images in 2006. The total area was 835.9 km² in 1992, 830.0 km² in 2000, and 864.8 km² in 2006, increasing by 3.46% from 1992 to 2006 (an average rate of 0.25% per year). The Fedchenko glacier system is relatively stable when considering glacier surging and data errors. Reanalysis data (eg for temperature and precipitation) from the US National Centers for Environmental Prediction and National Center for Atmospheric Research suggest that increasing precipitation since 1990 probably caused the slight change in glacier area.