Pine Island Glacier
NASA research flight over the Pine Iceland Glacier in November 2011
The Pine Iceland Glacier (English Pine Iceland Glacier, abbreviated PIG ) is a major river of ice of West Antarctica. The glaciated catchment area has an area of 162,300 km ², the ice of the glacier system account for about 10% of the West Antarctic ice sheet from. The Pine Iceland Glacier extends from the Hudson Mountains to the Pine - Iceland - bay in the southern Amundsen Sea, where it forms an ice shelf.
The Pine Iceland glacier moves more ice into the sea than any other glacier as well. As the glacier had a significantly negative mass balance in recent years, this contribution has increased. The ice thickness of the glacier, which is estimated at about two kilometers takes a year to about a meter from. This is the glacier, which relates the total mass loss, even the most dwindling worldwide.
The glacier has significantly retreated during the last 20 years. The so-called grounding line, ie the line from which the ice begins to float on the sea, has shifted over this period by about 20 kilometers towards the coast. Simulations of a published 2014 study suggest that the retreat because of the reliefs on the seabed significantly over the next few years, which has an even such a large five times annual mass loss. This predicted mass loss alone this glacier caused a sea level increase of 3.5 to 10 mm within the next 20 years.
Development
Currently, the Pine Iceland Glacier is responsible for 20 % of the mass loss of the West Antarctic Ice Sheet. The accelerated loss of thickness that is observed since the 1980s is attributed to subglacial melting at the base of the ice shelf, which has been reinforced by the recent intensification of the circulation of the Circumpolar Deep Water. From 1992 to 2011, an annual retreat of the grounding line were measured to 0.95 ± 0.09 km on basis of satellite images. It should be noted that in the retreat increasingly steep sloping seabed a retreat of the grounding line should actually have counteracted. It is assumed that the melting processes in the sea and the thinning of the ice shelf cause the glacier end of the ice stream opposes less resistance and thus is also responsible for the thinning of the continental part of the glacier.
Currently, the grounding line to a point where the sea floor does not rise to the coast but first drops again. The past has shown that such a constellation to the destabilization of tidal glaciers may result. Three different simulations for the Pine Iceland Glacier also come to the conclusion that the Pine Iceland Glacier is now quite rapidly withdraw another 40 kilometers. According to these simulations, the annual mass loss of the glacier, which had stood from 1992 to 2011 at 20 gigatons per year, over the next 20 years 100 gigatons per year - equivalent to a sea level increase of 3.5 to 10 mm during this period. In the following years, the mass loss remains, according to these simulations at a high level from 60 to 120 gigatons per year.
Another study published in 2014 clearly shows that the Pine Iceland Glacier is very sensitive to climate changes. While transported approximately 69 cubic kilometers of ice in 2010, the glacier melt water into the sea as he was in 2012 with about 35 cubic kilometers from only about half of melt water. The sharp decline in 2012 is probably due to the significant cooling of the Amundsen Sea. This was caused by the prevailing easterly winds, which were caused by a strong La Niña effect. Normally in this area westerly winds predominate.
In October 2011, the glacier had already drawn attention to himself than 20 km had formed behind the calving front is a 30 km long crack in the ice shelf. This led on 8 July 2013 figuring an iceberg with an area of around 720 sq km, which drove into the Amundsen Sea. Such a process, however, is not unusual and necessarily due in such glaciers to global warming.