Taku Glacier (

Lingít The Tlingit ( or ; also spelled Tlinkit) are indigenous peoples of the Pacific Northwest Coast of North America. Their language is the Tlingit language (natively , pronounced ),

tidewater glacier The tidewater glacier cycle is the typically centuries-long behavior of tidewater glaciers that consists of recurring periods of advance alternating with rapid retreat and punctuated by periods of stability. During portions of its cycle, a tidewate ...

located in Taku Inlet in the

U.S. state In the United States, a state is a constituent political entity, of which there are 50. Bound together in a political union, each state holds governmental jurisdiction over a separate and defined geographic territory where it shares its sover ...

Alaska Alaska ( ; russian: Аляска, Alyaska; ale, Alax̂sxax̂; ; ems, Alas'kaaq; Yup'ik: ''Alaskaq''; tli, Anáaski) is a state located in the Western United States on the northwest extremity of North America. A semi-exclave of the U.S., ...

, just southeast of the city of

Juneau The City and Borough of Juneau, more commonly known simply as Juneau ( ; tli, Dzánti K'ihéeni ), is the capital city of the state of Alaska. Located in the Gastineau Channel and the Alaskan panhandle, it is a unified municipality and the se ...

. Recognized as the deepest and thickest alpine temperate glacier known in the world, the Taku Glacier is measured at thick. It is about long, and is largely within the

Tongass National Forest The Tongass National Forest () in Southeast Alaska is the largest U.S. National Forest at . Most of its area is temperate rain forest and is remote enough to be home to many species of endangered and rare flora and fauna. The Tongass, which i ...

Ocean liner and glacier in art detail, Alaska via Canadian Pacific

The glacier was originally named Schultze Glacier in 1883 and the Foster Glacier in 1890, but ''Taku'', the name the local

Tlingit The Tlingit ( or ; also spelled Tlinkit) are indigenous peoples of the Pacific Northwest Coast of North America. Their language is the Tlingit language (natively , pronounced ),

natives had for the glacier, eventually stuck. It is nestled in the

Coast Mountains The Coast Mountains (french: La chaîne Côtière) are a major mountain range in the Pacific Coast Ranges of western North America, extending from southwestern Yukon through the Alaska Panhandle and virtually all of the Coast of British Columbia ...

and originates in the

Juneau Icefield The Juneau Icefield is an ice field located just north of Juneau, Alaska, continuing north through the border with British Columbia, extending through an area of in the Coast Range ranging north to south and east to west. The icefield is the so ...

. It is the largest glacier in the icefield and one of the southernmost tidewater glaciers of the

northern hemisphere The Northern Hemisphere is the half of Earth that is north of the Equator. For other planets in the Solar System, north is defined as being in the same celestial hemisphere relative to the invariable plane of the solar system as Earth's Nort ...

. The glacier, which converges with the

Taku River The Taku River (Lingít: ''T'aaḵu Héeni'') is a river running from British Columbia, Canada, to the northwestern coast of North America, at Juneau, Alaska. The river basin spreads across . The Taku is a very productive salmon river and its dra ...

at Taku Inlet, has a history of advancing until it blocks the

river A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases, a river flows into the ground and becomes dry at the end of its course without reaching another body of wate ...

, creating a

lake A lake is an area filled with water, localized in a basin, surrounded by land, and distinct from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, although, like the much large ...

, followed by a dramatic break of the ice dam. The most recent of these advances occurred in 1750. The glacier has advanced since 1890, and as of June 29, 2012 is from Taku Point. It is the only advancing glacier of the 20 major glaciers of the Juneau Icefield. If the advance continues it will again block the river, but this appears unlikely at present. Since 1946, the glacier has been monitored by the Juneau Icefield Research Program, which has documented its rate of advance since 1988 at a year. The advance is due to a positive

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 bee ...

; that is, more snow accumulates than snow and ice melt. Until 1948 the glacier had a calving front; since then the

terminus Terminus may refer to: * Bus terminus, a bus station serving as an end destination * Terminal train station or terminus, a railway station serving as an end destination Geography *Terminus, the unofficial original name of Atlanta, Georgia, United ...

has been grounded. Due to the positive mass balance and the fact that it was no longer losing mass to

iceberg An iceberg is a piece of freshwater ice more than 15 m long that has broken off a glacier or an ice shelf and is floating freely in open (salt) water. Smaller chunks of floating glacially-derived ice are called "growlers" or "bergy bits". The ...

s, Taku Glacier has become insensitive to the warming that has impacted all other glaciers of the icefield. This has driven its advance. The recent negative mass balance 1989-2005 is not large enough yet to stop the advance, but it is the first sign that the glacier's advance may not take it to Taku Point. Taku Glacier is the namesake of the

Alaska Marine Highway System The Alaska Marine Highway (AMH) or the Alaska Marine Highway System (AMHS) is a ferry service operated by the U.S. state of Alaska. It has its headquarters in Ketchikan, Alaska. The Alaska Marine Highway System operates along the south-central ...

ferry M/V ''Taku''. Taku Glacier was reported to be in retreat as of 2019.Mighty Glacier Finally Succumbs to Climate Change
/ref>

References

External links

Terminus Behavior of Juneau Icefield Glaciers 1948-2005

Mass balance of the Taku Glacier

Juneau Icefield Research Program
*
Pictures from the Juneau Icefield, including some from the Taku Glacier
. {{Authority control Glaciers of Alaska Glaciers of Juneau, Alaska Tongass National Forest

See also

References

External links