Grenzgletscher

The Gorner Glacier (german: Gornergletscher) is a valley glacier found on the west side of the Monte Rosa massif close to Zermatt in the canton of Valais, Switzerland. It is about long (2014) and wide. The entire glacial area of the glacier related to Gorner Glacier is (2007), which makes it the second largest glacial system in the Alps after the Aletsch Glacier system; however it ranks only third in length behind the Aletsch and Fiescher Glacier, respectively. Numerous smaller glaciers connect with the Gorner Glacier. Its (former) tributaries are
clockwise on this map
: ''Gornergletscher'' (after which the whole system is named, but the upper part is now disconnected from the lower part), ''Monte Rosa Gletscher'', ''Grenzgletscher'' (nowadays by far its main tributary, now disconnected from the actual Gornergletscher), ''Zwillingsgletscher'', ''Schwärzegletscher'', ''Breithorngletscher'', ''Triftjigletscher'', and '' Unterer Theodulgletscher'' (although the last three ones are actually disconnected now).

The Grenzgletscher ( en, Border Glacier) between the central Monte Rosa massif and the Liskamm to the south is nowadays by far the lower Gorner Glacier's main tributary. The Gorner Glacier's upper part is almost already disconnected from its lower part. Also the former tributaries ''Breithorngletscher'', ''Triftjigletscher'', and '' Unterer Theodulgletscher'' lost their connections to the Gorner Glacier during the last century; the Lower Theodul Glacier became disconnected in the 1980s.

An interesting feature of this glacier is the ''Gornersee'', an ice marginal lake at the confluence area of the Gorner- and Grenzgletscher. This lake fills every year and drains in summer, usually as a Glacial lake outburst flood. This is one of few glacial lakes in the Alps exhibiting this kind of behaviour.

There are also several interesting surface features including crevasses and "table top" forms where large surface boulders have been left stranded above the glaciers surface. These tabular rocks are supported by ice that the boulder has sheltered from melting that has effected the more exposed surrounding ice.

Due to the immense information about the glacier, it is perfect for a glacier project.

It is the source of the river Gornera, which flows down through Zermatt itself. However, most of its water is captured by a water catchment station of the Grande Dixence hydroelectric power plant. This water then ends up in the Lac des Dix, the main reservoir of Grande Dixence.

The glacier as well as the surrounding mountains can be seen from the Gornergrat (), connected from Zermatt by the Gornergrat Railway.

Retreating glacier(s)

Like almost all other glaciers in the Alps, and most glaciers on the globe as well, due to global warming the Gorner Glacier is a retreating glacier—and in quite a dramatic way. Nowadays (2014), Gorner Glacier retreats about every year, but with a record loss of in 2008. Since its last major expansion (in the modern era, after the last glacial period) in 1859, it lost more than in distance.

In these days ( 2015) this becomes quite obvious because the uneducated visitor usually misidentifies Gorner Glacier's main tributary as its upper part: the Grenzgletscher ( en, Border Glacier) on the south side of the central, visible Monte Rosa massif. However, the upper Gorner Glacier traditionally is to be found on the north side. The reason is that the upper part of the Gorner Glacier is currently losing contact with its lower part and now the Grenzgletscher has become its much larger tributary. So it is easy to mismatch the Border Glacier as the upper Gorner Glacier.

But this was not the case in earlier times, as the following comparison impressively shows (be also aware of the retreating of the Monte Rosa Glacier in the middle, the one in between Gorner and Border Glaciers):

Monte Rosa, Lyskamm, with Gorner Glacier, Valais, Alps of, Switzerland-LCCN2001703309.jpg, Around 1890–1900 (photomechanical print): The upper Gorner Glacier (left) obviously still is the main tributary of the lower part; the old Monte Rosa Hut (built 1894–95) would have been found just few metres above/next to the north-eastern border of the Grenzgletscher (in the middle; compare with the third picture)
Patrouille im Matterhorngebiet - CH-BAR - 3236968.tif, 1914–1918: Swiss Army patrol during World War I overlooking the confluence of the Gorner and Border Glaciers; even the Monte Rosa Glacier in the middle still has contact to the Gorner Glacier
Aerial Photo of Monte Rosa Massif - Wallis - Switzerland (cropped).jpg, 1994: Aerial photo from Aug. 1994 with Gorner glacier on the left, border glacier (Grenzgletscher) on the right, both framing the Monte Rosa massif in the middle
MonteRosaWestseite gesehenVomGornergrat.JPG, 2005: The connection between the upper and lower part is still given and the moraine is still clearly fed by its upper part; the old Monte Rosa Hut (2,795 m) is easily recognizable above the left over, north-eastern lateral moraine of the Border Glacier (in the middle, right)
Klein Matterhorn looking toward Gornergrat.jpg, 2007: The loss of thickness (about ) of the lower Gorner Glacier since its major expansion in 1859 is easily recognizable on the south flank of the Gornergrat by the left over and much higher situated lateral moraine (see the light-coloured part above the grey flank; as seen from Klein Matterhorn)
Wide view to Gornergletscher, Monte Rosa and Matterhorn, 2012 August.jpg, 2012: The upper Gorner Glacier is losing contact to its lower part; especially the middle moraine will stop being fed by its originally upper part

See also

*List of glaciers in Switzerland
*List of glaciers
*Retreat of glaciers since 1850
*Swiss Alps

References

External links

Gorner Glacier
glaciology.ethz.ch

swisseduc.ch

{{Authority control

Glaciers of Valais
Glaciers of the Alps