A glacier ( /ˈɡlæsiə/ GLASS-ee-ər or /ˈɡleɪʃər/ GLAY-shər) is a large persistent body of ice that forms where the accumulation of snow exceeds its ablation (melting and sublimation) over many years, often centuries. At least 0.1 km2 in area and 50 m thick, but often much larger, a glacier slowly deforms and flows due to stresses induced by its weight. Crevasses, seracs, and other distinguishing features of a glacier are due to its flow. Another consequence of glacier flow is the transport of rock and debris abraded from its substrate and resultant landforms like cirques and moraines. Glaciers form on land, often elevated, and are distinct from the much thinner sea ice and lake ice that form on the surface of bodies of water.
The word glacier comes from French. It is derived from the Vulgar Latin glacia and ultimately from Latin glacies meaning ice. The processes and features caused by glaciers and related to them are referred to as glacial. The process of glacier establishment, growth and flow is called glaciation. The corresponding area of study is called glaciology. Glaciers are important components of the global cryosphere.
On Earth, 99% of glacial ice is contained within vast ice sheets in the polar regions, but glaciers may be found in mountain ranges of every continent, and on a few high-latitude oceanic islands. Between 35°N and 35°S, glaciers occur only in the Himalayas, Andes, a few high mountains in East Africa, Mexico, New Guinea and on Zard Kuh in Iran.
Glacial ice is the largest reservoir of freshwater on Earth, supporting one third of the world's population. Many glaciers store water during one season and release it later as meltwater, a water source that is especially important for plants, animals and human uses when other sources may be scant.
Because glacial mass is affected by long-term climate changes, e.g., precipitation, mean temperature, and cloud cover, glacial mass changes are considered among the most sensitive indicators of climate change and are a major source of variations in sea level.
Other articles related to "glacier":
... The peak can be accessed via Hoper Glacier (Bualtar Glacier) and Barpu Glacier ... The top of the peak provides stunning views of Miar Peak (6,824 m), Miar Glacier and Phuparash Peak (6,574 m) ...
... Glacier Ridge Trail is a 14-mile-long (23 km) trail in Butler County, Pennsylvania ... Glacier Ridge Trail also comprises a small portion of the scenic North Country Trail, which stretches from New York to North Dakota ...
... There were 47 households out of which 17.0% had children under the age of 18 living with them, 38.3% were married couples living together, 4.3% had a female householder with no husband present, and 55.3% were non-families. 46.8% of all households were made up of individuals and 10.6% had someone living alone who was 65 years of age or older ...
... Keyhole Glacier is a glacier located in the central Baffin Mountains of northeastern Baffin Island, Nunavut, Canada ...
... The glacier, during its advance created many drumlins (a type of knoll) in the region, many of which have become the islands of Horicon Marsh ... During the glacier's retreat, a moraine was created, forming a natural dam holding back the waters from the melting glacier and forming Glacial Lake Horicon ...
Famous quotes containing the word glacier:
“The glacier knocks in the cupboard,
The desert sighs in the bed,
And the crack in the tea-cup opens
A lane to the land of the dead.”
—W.H. (Wystan Hugh)