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Petermann Glacier

Petermann Glacier
Greenland tmo 2003186.jpg
NASA satellite image.
Location within Greenland
Location within Greenland
Location within Greenland
Location Greenland
Coordinates 80°45′N 60°45′W / 80.750°N 60.750°W / 80.750; -60.750Coordinates: 80°45′N 60°45′W / 80.750°N 60.750°W / 80.750; -60.750
Length 70 km (43 mi)
Width 15 km (9.3 mi)
Thickness 600 m (2,000 ft)
Terminus Hall Basin

Petermann Glacier is a large glacier located in North-West Greenland to the east of Nares Strait. It connects the Greenland ice sheet to the Arctic Ocean near 81 degrees north latitude. It is named after the German cartographer August Heinrich Petermann

The tidewater glacier consists of a 70 km (43 mi) long and 15 km (9.3 mi) wide floating ice tongue whose thickness changes from about 600 m (2,000 ft) at its grounding line to about 30–80 metres (98–262 ft) at its front. Rough mass balance estimates using these scales suggest that about 80% of its mass is lost as basal meltwater, yet little oceanographic data are available to connect Petermann Glacier to its fjord and adjacent Nares Strait. Even the sill depth and location is largely unknown as modern soundings of the fjord, with its mouth located between Cape Morton and Cape Tyson, are still lacking. Petermann Glacier marks the western limit of Hall Land.

A series of satellite images from 2002 through 2009 illustrate that the terminus of the glacier has advanced towards the ocean, however, several lateral rifts have developed also. The distance of this rifts or cracks back from the terminus has diminished for this time period also and may serve as a precursor to natural ice calving from Petermann Glacier. A large chunk estimated to be 100 square miles (260 km2) calved off the glacier in August, 2010. The Danish Meteorological Institutes maintains an archive of imagery of Petermann Glacier and adjacent coastal areas of Greenland from both European and US satellites and sensors such as Envisat, MODIS, and AVHRR.

Data from Operation IceBridge show a 750 km long subglacial canyon running from the center of the island northward to the fjord of the Petermann Glacier. Dubbed "Greenland Grand Canyon" by media, the bottom is below sea level, and the canyon is likely to have influenced basal water flow from the ice sheet interior to the margin. The canyon predates ice sheet inception and has influenced basal hydrology in Greenland over past glacial cycles.


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