Amery Ice Shelf

Amery Ice Shelf
Name	Amery Ice Shelf
Location	East Antarctica

Amery Ice Shelf. It is one of the largest ice shelves in East Antarctica, located between the American Highland and the Ingrid Christensen Coast of Princess Elizabeth Land. The ice shelf is a critical outlet for the Lambert Glacier system, draining a significant portion of the continental interior into the Southern Ocean. Its dynamics are closely monitored as a key indicator of the health of the Antarctic ice sheet.

Geography and location

The Amery Ice Shelf is situated in a large embayment of the Antarctic continent, bounded by the Mawson Coast to the west and the Lars Christensen Land to the east. Its seaward front, which calves icebergs into the Prydz Bay, extends for approximately 200 kilometers along the Mac. Robertson Land coastline. The inland boundary is defined by the confluence of the massive Lambert Glacier, the Fisher Glacier, and the Mellor Glacier, which channel ice from the vast interior Dome A and Gamburtsev Mountain Range regions. The underlying Amery Basin is a significant geological feature beneath the ice.

Physical characteristics

The ice shelf exhibits a typical structure with a thick, floating ice plain that thickens significantly inland, reaching several hundred meters. Its surface features include extensive meltwater ponds in summer and prominent flow stripes visible from satellite imagery. The basal environment is complex, involving interactions with ocean waters from the Prydz Bay and subglacial water systems. The shelf's grounding line, where it begins to float, is a critical and dynamic boundary studied by projects like the International Thwaites Glacier Collaboration.

Research and exploration

Scientific investigation of the Amery Ice Shelf has been a focus for nations including Australia, the United States, and China. Key research stations in the region, such as Davis Station and Mawson Station, operated by the Australian Antarctic Division, provide logistical support. Major projects include long-term monitoring by the Scripps Institution of Oceanography and drilling programs to extract ice cores and access sub-ice-shelf cavities. Research vessels like the RV Investigator and the USCGC Polar Star frequently work in adjacent waters.

Role in the Antarctic ice sheet system

As the primary outlet for the Lambert Glacier basin, the Amery Ice Shelf regulates the flow of a major portion of the East Antarctic Ice Sheet. It acts as a buttress, slowing the seaward flow of inland ice; changes in its integrity can directly influence contributions to global sea level rise. Its interactions with warm Circumpolar Deep Water from the Southern Ocean are a critical control on basal melt rates. The shelf's behavior is integral to models developed by the Intergovernmental Panel on Climate Change and institutions like the British Antarctic Survey.

History of observations

The ice shelf was discovered during the British Australian New Zealand Antarctic Research Expedition led by Sir Douglas Mawson and named for William B. Amery, a politician in the British Parliament. Detailed mapping accelerated with the advent of the U.S. Navy's Operation Highjump and later satellite missions such as Landsat and ICESat. Notable calving events, including the breakoff of massive icebergs like Loose Tooth and D-28, have been tracked by agencies including NASA and the European Space Agency. The Soviet Antarctic Expedition also conducted early reconnaissance in the area.

Future and climate change impacts

Projections indicate the Amery Ice Shelf will experience increased basal melting due to incursions of warmer ocean currents, a process observed in the Amundsen Sea region. This could potentially destabilize its grounding line and accelerate ice flow from the Lambert Glacier. Its future is a major concern for organizations like the World Meteorological Organization and is a case study in international treaties like the Antarctic Treaty System. Long-term monitoring is essential for predicting its contribution to future sea level rise, with data contributing to global initiatives such as the Year of Polar Prediction.

Category:Ice shelves of Antarctica Category:Princess Elizabeth Land