Pine Island Glacier (PIG) is a large ice stream flowing west-northwest along the south side of the Hudson Mountains into Pine Island Bay, Amundsen Sea, Antarctica. It was mapped by the United States Geological Survey (USGS) from surveys and United States Navy (USN) air photos, 1960-66, and named by the Advisory Committee on Antarctic Names (US-ACAN) in association with Pine Island Bay.
The area drained by Pine Island Glacier comprises about 10 percent of the West Antarctic Ice Sheet.Satellite measurements have shown that the Pine Island Glacier Basin has a greater net contribution of ice to the sea than any other ice drainage basin in the world and this has increased due to recent acceleration of the ice stream.The ice stream is extremely remote, with the nearest continually occupied research station at Rothera, nearly 1,300 km (810 mi) away.The area is not claimed by any nations and the Antarctic Treaty prohibits any further claims while it is in force.
Ice Sheet Drainage:
The Antarctic ice sheet is the largest mass of ice on earth, containing a volume of water equivalent to 57 m (187 ft) of global sea level.The ice sheet forms from snow which falls onto the continent and compacts under its own weight. The ice then moves under its own weight toward the edges of the continent. Most of this transport to the sea is by ice streams (faster moving channels of ice surrounded by slower moving ice walls) and outlet glaciers.The Antarctic ice sheet consists of the large, relatively stable, East Antarctic Ice Sheet and a smaller, less stable, West Antarctic Ice Sheet.
From The Sea:
The first ship to reach Pine Island Glacier's ice shelf, in Pine Island Bay, was the USS/USCGC Glacier in 1985. This ship was an icebreaker operated by the U.S. Coast Guard. The mission, known as Deep Freeze, had scientists on board who took sediment samples from the ocean floor.During the summer field season, over two months from January to February 2009, researchers aboard the U.S. Antarctic Program research vessel Nathaniel B. Palmer reached the ice shelf. This was the second time that the Palmer had successfully made it up to the glacier, the first time being in 1994. In collaboration with the British, the scientists used a robotic submarine to explore the glacier-carved channels on the continental shelf as well as the cavity below the ice shelf and glacier.
The submarine, known as Autosub 3, was developed and built at the National Oceanography Centre in the UK. It completed six successful missions, travelling a total of 500 km (310 mi) under the ice shelf.Autosub is able to map the base of the ice shelf as well as the ocean floor and take various measurements and samples of the water on the way. The success of Autosub 3 was particularly notable because its predecessor Autosub 2 was lost beneath the Fimbul Ice Shelf on only its second such mission.