Sperry Glacier is a
glacier on the north slopes of
Gunsight Mountain
Gunsight Mountain is a prominent elevation summit located northeast of Palmer in the Talkeetna Mountains of the U.S. state of Alaska. This landmark is set midway between Palmer and Glennallen, with the Glenn Highway traversing the southern base ...
west of the
Continental Divide
A continental divide is a drainage divide on a continent such that the drainage basin on one side of the divide feeds into one ocean or sea, and the basin on the other side either feeds into a different ocean or sea, or else is endorheic, not ...
in
Glacier National Park in the
U.S. state of
Montana. Although many geologic features of Glacier National Park were formed during the
much longer period of glaciation ending over 10,000 years ago, Sperry Glacier — like all the glaciers in the park today — is a product of the recent
Little Ice Age
The Little Ice Age (LIA) was a period of regional cooling, particularly pronounced in the North Atlantic region. It was not a true ice age of global extent. The term was introduced into scientific literature by François E. Matthes in 1939. Ma ...
, the period of cooler average temperatures starting in about the 13th century and concluding in the mid-19th century.
Once one of the largest glaciers in the park, the surface area of Sperry Glacier has
retreated 75 percent since the mid-19th century. 2005 measurements of the surface area of the glacier resulted in an estimated area of , whereas the glacier is estimated to have covered an area of at the end of the Little Ice Age in the mid-19th century. The glacier lost almost 35 percent of its surface area between 1966 and 2005.
[ The glacier is named for ]Lyman B. Sperry
Lyman Beecher Sperry (1841-1923) was a physician, lecturer, and author. Nicknamed "The Gentleman Explorer", he was the discoverer of Sperry Glacier in Glacier National Park in Montana, and was influential in the park's promotion to national park ...
, a professor from Oberlin College
Oberlin College is a Private university, private Liberal arts colleges in the United States, liberal arts college and conservatory of music in Oberlin, Ohio. It is the oldest Mixed-sex education, coeducational liberal arts college in the United S ...
, who in 1895 participated in an expedition to explore the geography and map the region wh