Glaciers and ice features

Ablation zone

The ablation zone is the lower part of a glacier where melting and calving remove more ice than snowfall adds, separated from the accumulation zone by the equilibrium line.

Academy of Sciences Ice Cap, on Komsomolets Island, Severnaya Zemlya, Russia; largest ice cap in the Russian Arctic at 5,575 km², 749 m summit, 2,184 km³ volume, 42% marine margin, near-zero climatic mass balance.

Agassiz Ice Cap

Agassiz Ice Cap, Ellesmere Island, Nunavut, Canada; large high Arctic ice cap (~17,300–21,000 km²) named for Louis Agassiz; official since 1967; ice cores show recent melt highest in 4200 years.

Aletsch Glacier

Aletsch Glacier (Aletschgletscher), Switzerland's largest and longest Alpine glacier at 22.6 km and 83 km², a UNESCO World Heritage site retreating since 1860 and projected to lose most of its volume by 2100.

Antarctic ice sheet

The Antarctic ice sheet, also called the Antarctic ice cap, is the ice mass covering almost all of Antarctica, holding about 58 meters of potential sea level rise.

Asgardfonna

Asgardfonna (Åsgardfonna) is an ice cap in Ny-Friesland, Spitsbergen, Svalbard, between Wijdefjorden and Lomfjorden, about 1,230 km²; with Balderfonna and Olaf V it forms Svalbard's largest glacier complex.

Athabasca Glacier

Athabasca Glacier, an outlet glacier of the Columbia Icefield in Jasper National Park, Alberta; Canada's most accessible glacier, 8.3 km long, retreating since its 1843/4 Little Ice Age maximum and thinned 60 m from 1961 to 2020.

Aurora Basin

Aurora Basin (Aurora Subglacial Basin): large marine-based subglacial basin in Wilkes Land, East Antarctica, named for the AAE ship Aurora; its outlet glaciers, led by Totten, dominate East Antarctic ice loss. Distinct from the small Halmahera Sea undersea Aurora Basin adopted by GEBCO in 2023.

Bach Ice Shelf

Bach Ice Shelf, an ice shelf in the southern embayment of Alexander Island, west Antarctic Peninsula, named after Johann Sebastian Bach. Area about 4,536 km² in 2010, sustained retreat, decoupling from the Monteverdi Peninsula pinning point, and resumed meltwater export.

Barentsjokulen

Barentsjokulen (Barentsjøkulen) is a 571 km² ice cap on Barentsøya, Svalbard, with four tidewater outlet glaciers including Freemanbreen, which surged in 1956; maximum measured ice thickness 270 m.

Barnes Ice Cap

Barnes Ice Cap, a roughly 5,900 km² bowling-pin-shaped ice cap on central Baffin Island, Nunavut, Canada, is the last remnant of the Laurentide Ice Sheet, holds Canada's oldest known ice (~20,000 years), and is projected to disappear within 300 years.

Basal sliding

Basal sliding is the movement of glacier ice over its bed, controlled by water pressure at the base and one of three processes of glacier motion.

Bertrab Nunatak

Bertrab Nunatak, a c. 500 m rock outcrop southeast of Vahsel Bay, Luitpold Coast, Coats Land, Antarctica; mapped by the German Antarctic Expedition 1911-12 and site of Argentina's Belgrano II station.

Bingham Glacier

Bingham Glacier is a large outlet glacier in Palmer Land on the east coast of the Antarctic Peninsula, flowing east to the Larsen Ice Shelf.

Blood Falls

Blood Falls is a red, iron-rich hypersaline brine discharging episodically from the Taylor Glacier terminus into Lake Bonney, McMurdo Dry Valleys, Antarctica. Discovered by Griffith Taylor in 1911; its color comes from oxidizing iron nanospheres, and its ancient marine brine hosts microbes isolated for over a million years.

Brasvellbreen

Bråsvellbreen (Brasvellbreen), southernmost outlet of the Austfonna ice cap on Nordaustlandet, Svalbard; a surge-type tidewater glacier, about 45 km long, that advanced roughly 20 km in the 1930s in Svalbard's largest recorded surge and is now retreating.

Butler Island

Butler Island, an ice rise in the Larsen Ice Shelf on the Black Coast, Antarctic Peninsula, at 72°12'S 60°20'W; named in 1953 for FIDS commander Kenelm Pierce-Butler and host to a BAS automatic weather station.

Cambria Icefiled

Cambria Icefield (formerly Cambria Snowfield) is a 715 km² icefield in the Boundary Ranges, Coast Mountains, about 35 km southeast of Stewart, British Columbia, feeding the Bromley, Bear River, South Flat, and White glaciers.

Casey Glacier

Casey Glacier is a glacier about 6 miles wide on the east coast of Palmer Land, Antarctic Peninsula, named by Sir Hubert Wilkins in 1928 for R.G. Casey.

Castor Nunatak

Castor Nunatak, a rock peak in the Seal Nunataks group off the east coast of the Antarctic Peninsula; discovered by Larsen in 1893, named for the sealing ship Castor, confirmed as a nunatak in 1902.

Christensen Nunatak

Christensen Nunatak, a c. 300 m Seal Nunatak at 65°06'S 59°31'W on the NE side of Robertson Island, Antarctica; discovered by Larsen in 1893 as 'Christensen Island', a volcanic vent named for whaler Christen Christensen.

Columbia Icefield

Columbia Icefield (champ de glace Columbia): largest icefield in the Canadian Rockies, straddling the Alberta-BC Continental Divide; feeds the Athabasca, Saskatchewan, and Columbia rivers draining to three oceans.

Crevasse

Crevasse: a crack or series of cracks in a moving glacier's surface caused by differential flow stresses, also called glacier fissures. Forms where tensile stress exceeds 30–80 kPa; water-filled crevasses can penetrate to the bed via hydrofracture, driving calving and meltwater routing.

Cryoseism

Cryoseism (frost quake, ice quake): a non-tectonic seismic event caused by sudden cracking of frozen soil, rock, or ice, ranging from small surface frost quakes to large glacial earthquakes from iceberg calving in Greenland and Antarctica.

Cryosphere

The cryosphere (from Greek krios, cold) is Earth's frozen water: ice sheets, glaciers, snow, sea ice, and permafrost. It regulates climate via albedo, feeds 2 billion people's water, and is losing ice rapidly.

Devon Ice Cap

Devon Ice Cap, a roughly 14,000 km² ice cap on Devon Island, Nunavut, Canada, one of the largest Canadian Arctic ice caps, monitored for mass balance since 1961 and losing mass at about −1.08 Gt per year.

DISC Drill (ice drilling system)

The DISC (Deep Ice Sheet Coring) Drill is an electromechanical drill built for the NSF that drilled the deepest U.S. ice core, 3,405 m, at WAIS Divide.

Dome A (domo a)

Dome A (Dome Argus) is the highest point of the Antarctic ice sheet, 4,093 m, in East Antarctica, over the Gamburtsev Subglacial Mountains. Site of China's Kunlun Station (2009), automated weather stations, ice coring, and leading astronomical observation.

Dome C

Dome C, also called Dome Concordia, is an East Antarctic ice dome hosting Concordia Station, best known as the EPICA deep ice core drilling site.