Columbia Glacier, Alaska: changes in velocity 1977-1986

The Columbia Glacier, a grounded, iceberg-calving tidewater glacier near Valdez, Alaska, began to retreat about 1977. Drastic retreat occurred in 1984, and by early 1986, retreat amounted to 2km. The glacier has thinned more than 100m since 1974 at a point 4km behind the 1974 terminus position. Between 1977 and 1985 the lower glacier ice velocity increased from 3-8m/d to 10-15m/d. -from Authors