Glacier Peak - Glaciers

Glaciers

Eleven significant glaciers cover Glacier Peak. When C.E. Rusk first saw these glaciers in 1906 they were beginning to retreat, but were still very advanced. The average retreat of Glacier Peak glaciers from the Little Ice Age to the 1958 positions was 5,381 feet (1,640 m). Richard Hubley noted that North Cascade glaciers began to advance in the early 1950s, after 30 years of rapid retreat. The advance was in response to a sharp rise in winter precipitation and a decline in summer temperature beginning in 1944. Ten of the fifteen glaciers around Glacier Peak advanced, including all of the glaciers directly on the mountain's slopes. Advances of Glacier Peak glaciers ranged from 50 to 1,575 feet (15 to 480 m) and culminated in 1978. All eleven Glacier Peak glaciers that advanced during the 1950–79 period emplaced identifiable maximum advance terminal moraines. From 1984 to 2005, the average retreat of eight Glacier Peak glaciers from their recent maximum positions was 1,017 feet (310 m). Milk Lake Glacier, on the north flank of the mountain, melted away altogether in the 1990s.