A tarn (or corrie loch) is a mountain

lake A lake is often a naturally occurring, relatively large and fixed body of water on or near the Earth's surface. It is localized in a basin or interconnected basins surrounded by dry land. Lakes lie completely on land and are separate from ...

, pond or pool, formed 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 ...

(or "corrie") excavated by a

glacier A glacier (; or ) is a persistent body of dense ice, a form of rock, that is constantly moving downhill under its own weight. A glacier forms where the accumulation of snow exceeds its ablation over many years, often centuries. It acquires ...

. A

moraine A moraine is any accumulation of unconsolidated debris (regolith and Rock (geology), rock), sometimes referred to as glacial till, that occurs in both currently and formerly glaciated regions, and that has been previously carried along by a gla ...

may form a natural dam below a tarn.

Etymology

The word is derived from the

Old Norse Old Norse, also referred to as Old Nordic or Old Scandinavian, was a stage of development of North Germanic languages, North Germanic dialects before their final divergence into separate Nordic languages. Old Norse was spoken by inhabitants ...

word ''tjörn'' ("a small mountain lake without tributaries") meaning pond. In parts of

Northern England Northern England, or the North of England, refers to the northern part of England and mainly corresponds to the Historic counties of England, historic counties of Cheshire, Cumberland, County Durham, Durham, Lancashire, Northumberland, Westmo ...

– predominantly Cumberland and

Westmorland Westmorland (, formerly also spelt ''Westmoreland''R. Wilkinson The British Isles, Sheet The British IslesVision of Britain/ref>) is an area of North West England which was Historic counties of England, historically a county. People of the area ...

(where there are 197), but also areas of North

Lancashire Lancashire ( , ; abbreviated ''Lancs'') is a ceremonial county in North West England. It is bordered by Cumbria to the north, North Yorkshire and West Yorkshire to the east, Greater Manchester and Merseyside to the south, and the Irish Sea to ...

and

North Yorkshire North Yorkshire is a Ceremonial counties of England, ceremonial county in Northern England.The Unitary authorities of England, unitary authority areas of City of York, York and North Yorkshire (district), North Yorkshire are in Yorkshire and t ...

– 'tarn' is widely used as the name for small lakes or

pond A pond is a small, still, land-based body of water formed by pooling inside a depression (geology), depression, either naturally or artificiality, artificially. A pond is smaller than a lake and there are no official criteria distinguishing ...

s, regardless of their location and origin (e.g. Talkin Tarn, Urswick Tarn, Malham Tarn). Similarly, in

Scandinavian languages The North Germanic languages make up one of the three branches of the Germanic languages—a sub-family of the Indo-European languages—along with the West Germanic languages and the extinct East Germanic languages. The language group is al ...

, a ''tjern'' or ''tjørn'' (both Norwegian) or ''tjärn'' or ''tärn'' (both Swedish) is a small natural lake, often in a forest or with vegetation closely surrounding it or growing into the tarn. The name of the Tjörnin in Reykjavik, Iceland is also from a related word. The specific technical use for a body of water in a glacial corrie comes from the high number of tarns found in corries in the

Lake District The Lake District, also known as ''the Lakes'' or ''Lakeland'', is a mountainous region and National parks of the United Kingdom, national park in Cumbria, North West England. It is famous for its landscape, including its lakes, coast, and mou ...

, an upland area in North-West England. Nonetheless, there are many more bodies of water called 'tarn' in the Lake District than actually fit this technical use. The Scots language word ''shon''/''shun'' ("a small

loch ''Loch'' ( ) is a word meaning "lake" or "inlet, sea inlet" in Scottish Gaelic, Scottish and Irish Gaelic, subsequently borrowed into English. In Irish contexts, it often appears in the anglicized form "lough". A small loch is sometimes calle ...

") may too be derived from Old Norse ''tjørn'', perhaps under the influence of ''sjø'' ("sea; fresh water lake").

Formation

Tarns are the result of small glaciers called

glaciers. Glacial cirques (or 'corries') form as hollows on mountainsides near the

firn line __NOTOC__ Firn (; from Swiss German "last year's", cognate with ''before'') is partially compacted névé, a type of snow that has been left over from past seasons and has been recrystallized into a substance denser than névé. It is ice th ...

. Eventually, the hollow in which a cirque glacier develops may become a large bowl shape in the side of the mountain, caused by weathering, by ice segregation, and as well as being eroded by plucking. The basin will become deeper as it continues to be eroded by ice segregation and abrasion. A cirque typically will be partially surrounded on three sides by steep

cliff In geography and geology, a cliff or rock face is an area of Rock (geology), rock which has a general angle defined by the vertical, or nearly vertical. Cliffs are formed by the processes of weathering and erosion, with the effect of gravity. ...

s, with a fourth side a form of

constructed from glacial till, which forms the ''lip'', ''threshold'' or ''sill'', from which either a stream or glacier will flow away from the cirque. Tarns form from the melting of the cirque glacier. They may either be seasonal features as supraglacial lakes, or permanent features which form in the hollows left by cirques in formerly glaciated areas.

Gallery

File:Adirondack Mountains, N.Y.- Lake Tear of the Clouds by Stoddard, Seneca Ray.png, Lake Tear of the Clouds (tarn) in the

Adirondack Mountains The Adirondack Mountains ( ) are a massif of mountains in Northeastern New York which form a circular dome approximately wide and covering about . The region contains more than 100 peaks, including Mount Marcy, which is the highest point in Ne ...

, New York, photo c. 19th century File:Velke Hincovo pleso.jpg, Veľké Hincovo, Tatra Mts, the largest and deepest tarn in

Slovakia Slovakia, officially the Slovak Republic, is a landlocked country in Central Europe. It is bordered by Poland to the north, Ukraine to the east, Hungary to the south, Austria to the west, and the Czech Republic to the northwest. Slovakia's m ...

File:Lousy Lake (tarn) N. Cascades Nat. Park, Pickett Range WA.jpg, Lousy Lake (tarn) in North Cascades National Park, Picket Range, Washington, USA File:Pond at Lakes of the Clouds.JPG, Lakes of the Clouds, below Mount Washington in the White Mountains File:Banderishki chukar.JPG, Banderishki Chukar seen from the Banderishki Lakes (tarns), Pirin Mountain,

Bulgaria Bulgaria, officially the Republic of Bulgaria, is a country in Southeast Europe. It is situated on the eastern portion of the Balkans directly south of the Danube river and west of the Black Sea. Bulgaria is bordered by Greece and Turkey t ...

File:Pirin - Gergiysko ezero, vrah Sinanitsa - IMG 4448.jpg, A view to Gergiysko lake (tarn) and Sinanitsa Peak, Pirin Mountain,

File:Страшното езеро.jpg, The Dreadful Lake (tarn), Rila Mountain,

File:Pogled kum ezerata ot biloto.JPG, The

Seven Rila Lakes The Seven Rila Lakes (, ) are a group of glacial lakes, situated in the northwestern Rila Mountain in Bulgaria. Situated between 2,100 and 2,500 metres elevation above sea level, they are the most visited group of lakes in Bulgaria. Each lake ca ...

(tarns), Rila Mountain,

Image:Maritsaorigin2.JPG, Marichini lakes (tarns), the origin of the

Maritsa Maritsa or Maritza ( ), also known as Evros ( ) and Meriç ( ), is a river that runs through the Balkans in Southeast Europe. With a length of ,

river seen from Musala peak, Rila Mountain,

Sea-Lion-Tarn-2.jpg, Sea Lion Tarn on

Livingston Island Livingston Island (Russian name ''Smolensk'', ) is an Antarctic island in the Southern Ocean, part of the South Shetland Islands, South Shetlands Archipelago, a group of List of Antarctic and subantarctic islands, Antarctic islands north of the ...

in Antarctica

References

External links

* * {{pond *

Etymology

Formation

Gallery

See also

References

External links