Lower Curtis Glacier is in

North Cascades National Park North Cascades National Park is a List of national parks of the United States, national park of the United States in Washington (state), Washington. At more than , it is the largest of the three National Park Service units that comprise the No ...

in the U.S. state of

Washington Washington most commonly refers to: * George Washington (1732–1799), the first president of the United States * Washington (state), a state in the Pacific Northwest of the United States * Washington, D.C., the capital of the United States ** A ...

. Named for photographer

Asahel Curtis Asahel Curtis (1874–1941) was an American photographer based in the Pacific Northwest region of the United States. His career included documentation of the Klondike Gold Rush, Klondike Gold Rush period in Seattle, natural landscapes in the N ...

, the glacier is in a

cirque A (; from the Latin word ) is an amphitheatre-like valley formed by Glacier#Erosion, glacial erosion. Alternative names for this landform are corrie (from , meaning a pot or cauldron) and ; ). A cirque may also be a similarly shaped landform a ...

on the western slopes of

Mount Shuksan Mount Shuksan is a glaciated massif in the North Cascades National Park. Shuksan rises in Whatcom County, Washington immediately to the east of Mount Baker, and south of the Canada–US border. The mountain's name ''Shuksan'' is derived fr ...

. Lower Curtis Glacier is rapidly retreating and has a negative

mass balance In physics, a mass balance, also called a material balance, is an application of conservation of mass to the analysis of physical systems. By accounting for material entering and leaving a system, mass flows can be identified which might have ...

, meaning that the rate of snow and ice that is falling in the

accumulation zone On a glacier, the accumulation zone is the area above the firn line, where snowfall accumulates and exceeds the losses from ablation, ( melting, evaporation, and sublimation). The annual equilibrium line separates the accumulation and ablation ...

is less than that which is lost each year in the

ablation zone Ablation zone or ''ablation area'' refers to the low-altitude area of a glacier or ice sheet below firn with a net loss in ice mass. This loss can result from melting, sublimation, evaporation, ice calving, aeolian processes like blowing snow, ...

. Between 1908 and 1984, the glacier experienced a loss of thickness by 45 meters (147 ft). Between 1984 and 2002, the glacier lost another 6 meters (19 ft) in thickness. Lower Curtis Glacier also lost 28% of its surface area between the end of the

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. Mat ...

(around 1850) and 1950. Between the years 1951 and 1979, the glacier actually lengthened by 245 meters (800 ft) but has retreated 184 m (600 ft) since 1985, partly due to the tongue of the glacier being on a steep precipice which may have increased the loss of ice at the termini.

References

{{reflist Glaciers of the North Cascades Glaciers of Whatcom County, Washington Glaciers of Washington (state)

See also

References