Petermann glacier
| Petermann glacier | ||
|---|---|---|
 Satellite photo |
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| location | Northwest Greenland | |
| Type | Outlet glacier | |
| width | Max. 15 km | |
| Ice thickness | Max. 600 m | |
| Coordinates | 81 ° 0 ′ N , 61 ° 0 ′ W | |
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The Petermann Glacier is in the northwest of Greenland situated, about 1300 square kilometer glacier , which according to the German geographer August Petermann is named.
It is one of 130 ice fields that are fed by the Greenland Ice Sheet . A special feature is the approximately 70 km long and 15 km wide glacier tongue floating in the water that fills the Petermann Fjord. Together with the Humboldt Glacier in the south, the catchment area is 121,000 km², which corresponds to 10% of the total area of the catchment areas of all Greenland glaciers. In the summer of 2009, the glacier was examined in detail as part of an expedition supported by Greenpeace , among others . On August 5, 2010, the glacier received international attention when the largest ice break in the Arctic since 1962 occurred on its tongue. A 260 km² iceberg (more than three times the area of Lake Chiemsee ) broke off the ice tongue and drifted into the open sea. On July 19, 2012, a large tongue of ice broke off again, the extent of which is given as twice the size of Manhattan Island. However, since the ice in question was already in the water, this had no effect on the sea level.
In 2013, by analyzing data from a special ground penetrating radar that penetrates the ice, one of the world's largest canyons was discovered under the northern ice sheet. This winds its way from the center of Greenland towards the north coast, where it flows under the Petermann Glacier into the Hall Basin. The gorge is at least 750 km longer than the Grand Canyon and is therefore also called the Grand Canyon of Greenland . It is up to 10 km wide and up to 800 meters deep. The gorge is older than the 1.6 million year old Greenland Ice Sheet.
According to computer simulations from 2019, there is a possibility that there is currently a gigantic subglacial river under the Greenland Ice Sheet at a depth of 300 to 500 m, which is fed by meltwater . The river is said to be up to 1,600 km long and stretch from the central ice plateau in the middle of Greenland to the Petermann Fjord in the north, where it flows under the ice into the sea. For comparison: the length of Greenland in north-south direction is 2650 km. The water of this river does not see any sunlight along its entire length, as it flows deep under the ice. Therefore, the researchers called this river a " dark river ".
Web links
- NASA Earth Observatory , Petermann Glacier, Greenland, image of the day, August 30, 2007 (English)
- Hamburger Abendblatt : The fall of the Petermann Glacier from July 23, 2009
- Der Spiegel : Huge glacier shows threatening cracks from August 22, 2008
- ESA Earth from Space: Petermann Glacier, Youtube from September 8, 2017.
Individual evidence
- ↑ Eric Rignot , Pannir Kanagaratnam: Changes in the Velocity Structure of the Greenland Ice Sheet ( Memento of the original dated February 22, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. (PDF; 395 kB). In: Science 311, 2006, pp. 986-990, Table 1
- ^ The Daily Telegraph : Greenpeace in Greenland: The Arctic Sunrise surveys the Petermann glacier
- ↑ Glacier Kalbt Riesen-Eisinsel - Article on scinexx.de, accessed on August 10, 2010
- ↑ Jonathan L. Bamber, Martin J. Siegert, Jennifer A. Griggs, Shawn J. Marshall, Giorgio Spada: Paleofluvial Mega-Canyon Beneath the Central Greenland Ice Sheet . In: Science 341, No. 6149, August 30, 2013, pp. 997-999, doi : 10.1126 / science.1239794
- ↑ Becky Oskin: 'Grand Canyon' of Greenland Discovered Under Ice Sheet . In: livescience, August 29, 2013
- ^ Christopher Robert Scott Chambers et al .: On the Possibility of a Long Subglacial River Under the North Greenland Ice Sheet. AGU Fall Meeting December 2019, December 9, 2019, accessed December 19, 2019 .
