Amundsen Sea — LLMpedia

Amundsen Sea
Polargeo · Public domain · source
Name	Amundsen Sea
Caption	Location off West Antarctica
Location	Southern Ocean
Coordinates	73°S 115°W
Type	Marginal sea
Basin countries	Antarctica
Area	500000 km²

Contents

Amundsen Sea The Amundsen Sea lies off the coast of Antarctica and forms part of the Southern Ocean margin adjacent to Marie Byrd Land and the Bellingshausen Sea boundary, bounded by the Pacific Ocean sector and flanked by major ice outlets such as the Thwaites Glacier, Pine Island Glacier, and tributary ice streams associated with the West Antarctic Ice Sheet. Exploratory and scientific histories connect the region to figures and expeditions including Roald Amundsen, the United States Antarctic Program, and research vessels such as RV Nathaniel B. Palmer, while international coordination occurs through bodies like the Scientific Committee on Antarctic Research and the International Council for Science.

Geography

The sea forms a embayment between geographic features including the Getz Ice Shelf, the Eights Coast, and the offshore Amundsen Polynya region, lying seaward of the Ross Sea and the Weddell Sea sectors. Islands and submarine features near the basin include the Thurston Island margin, the continental shelf break adjacent to the Bellingshausen Plate tectonic province, and bathymetric depressions mapped by surveys from platforms like RV Polarstern and research carried out by teams from British Antarctic Survey and Lamont–Doherty Earth Observatory. Shipping routes for scientific and logistical operations often stage from bases such as McMurdo Station, Palmer Station, and international Antarctic programs managed by nations including the United States, United Kingdom, Australia, and Argentina.

Marine-terminating outlets draining into the sea include major glaciers and ice streams monitored by agencies such as NASA and European Space Agency through missions like ICESat and Sentinel-1, with focal study on grounding line retreat, basal melting, and ice cliff dynamics informed by researchers at institutions including Scripps Institution of Oceanography and University of Washington. The behavior of the Pine Island Glacier and Thwaites Glacier is linked to processes such as marine ice sheet instability and sub-shelf cavity circulation observed by autonomous platforms like Argo floats and under-ice vehicles similar to operations by Woods Hole Oceanographic Institution. Seismic and radar campaigns by teams from United States Geological Survey and Scott Polar Research Institute have characterized basal conditions, while theoretical frameworks from Pierre P. Gilbert-style grounding line models and the Weertman sliding laws inform projections used by the Intergovernmental Panel on Climate Change.

Oceanographic regimes are shaped by interactions among the Antarctic Circumpolar Current, polynyas, and incursions of relatively warm modified Circumpolar Deep Water onto the continental shelf, a process observed by programs including Southern Ocean Observing System and modeled in coupled systems developed at NOAA and Met Office Hadley Centre. Regional atmospheric forcing from the Amundsen Sea Low and teleconnections with modes such as the El Niño–Southern Oscillation, Southern Annular Mode, and the Pacific Decadal Oscillation influence wind stress, sea ice variability, and heat transport. Paleoclimate reconstructions from ice cores analyzed by teams at British Antarctic Survey and University of Cambridge constrain Holocene and Pleistocene variability, while satellite altimetry from TOPEX/Poseidon and CryoSat documents contemporary sea surface height and ice elevation trends.

Marine ecosystems in the basin support trophic webs involving species studied by ecologists from Monterey Bay Aquarium Research Institute and the Australian Antarctic Division, including krill predators such as Antarctic fur seal, Weddell seal, and seabirds like Adélie penguin and Antarctic petrel, with foraging dynamics linked to sea ice extent and polynya productivity documented by the Commission for the Conservation of Antarctic Marine Living Resources. Benthic communities on the continental shelf host sponges, echinoderms, and suspension feeders sampled during expeditions led by research programs at National Institute of Water and Atmospheric Research and Consiglio Nazionale delle Ricerche. Microbial and phytoplankton assemblages responding to iron and light limitation have been characterized by studies from MBARI and university groups at University of Tasmania and McGill University.

Human presence is primarily scientific and logistical, coordinated under the Antarctic Treaty System and facilitated by research stations including Palmer Station and seasonal field camps supported by vessels such as ARA Puerto Deseado and icebreakers from Russian Antarctic Expedition. Major international projects include collaborative surveys by the International Thwaites Glacier Collaboration, joint remote sensing campaigns involving NASA and ESA, and field studies supported by universities like Columbia University and University of Oxford. Historical expeditions relevant to regional discovery and mapping include contributions from Roald Amundsen era voyages and aerial surveys conducted by Operation Highjump and later aerial mapping by US Navy assets.

Retreat and enhanced basal melting of glaciers draining into the sea raise concerns evaluated by the Intergovernmental Panel on Climate Change, with potential contributions to global sea level rise comparable in significance to melting from the Greenland ice sheet and parts of the East Antarctic Ice Sheet. Climate model ensembles from centers including IPSL, GFDL, and Hadley Centre explore scenarios for collapse thresholds and rate uncertainties, while mitigation and adaptation discourse involves stakeholders represented at United Nations Framework Convention on Climate Change negotiations. Conservation and management are framed by instruments such as the Convention on the Conservation of Antarctic Marine Living Resources and monitoring initiatives supported by the Scientific Committee on Antarctic Research to inform policymaking by treaty consultative parties including Chile, New Zealand, Norway, and United States.

Category:Seas of Antarctica