Amundsen Sea
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What is the Amundsen Sea?
The Amundsen Sea, an arm of the Southern Ocean, adjoins West Antarctica and is located south of approximately 70° S latitude. It is bordered by Cape Dart on Siple Island to the west and Cape Flying Fish to the east.
The sea includes the ice-covered coast of Marie Byrd Land, known as the Amundsen Sea Embayment. The sea is home to various wildlife, such as crabeater seals, minke whales, fin whales, killer whales, emperor and Adélie penguins, petrels, and hundreds of deep-sea invertebrate species.
The Thwaites Glacier drains into the Amundsen Sea. The collapse of the Thwaites Glacier could cause a significant rise in worldwide sea levels.
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Where is the Amundsen Sea located?
The Amundsen Sea, an arm of the Southern Ocean, adjoins West Antarctica, south of approximately 70° S latitude. It is bordered to the west by Cape Dart on Siple Island and to the east by Cape Flying Fish at the northwestern edge of Thurston Island. The sea includes the ice-covered coast of Marie Byrd Land, known as the Amundsen Sea Embayment. The Amundsen Sea was initially surveyed in February 1929 by Norwegian explorer Captain Nils Larsen, who named it after Norwegian polar explorer Roald Amundsen.
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Which continent is closest to the Amundsen Sea?
The Amundsen Sea, an arm of the Southern Ocean adjoining West Antarctica, is closest to the continent of Antarctica. Specifically, it borders Marie Byrd Land in western Antarctica. The sea is situated south of 70° S latitude and is bordered by Cape Dart on Siple Island to the west and Cape Flying Fish on the northwestern edge of Thurston Island to the east. The Amundsen Sea Embayment, an ice-covered portion of Marie Byrd Land, is also included within the sea's boundaries.
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Who is the Amundsen Sea named after?
The Amundsen Sea is named after Roald Amundsen, a renowned Norwegian polar explorer who lived from 1872 to 1928. He was the first explorer to reach the South Pole. The Amundsen Sea, an arm of the Southern Ocean near West Antarctica, was first surveyed in February 1929 by Norwegian explorer Captain Nils Larsen, who named it in Amundsen's honor.
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What are some key features of the Amundsen Sea's environment?
The Amundsen Sea, an arm of the Southern Ocean adjoining West Antarctica, is characterized by several key environmental features. Its temperature typically ranges from 30 to 35 °F (-1.1 to 1.7 °C). The sea is also home to various wildlife, albeit in low densities, including marine mammals like crabeater seals, minke whales and fin whales, and killer whales (orcas). It further serves as a habitat for seabirds, such as emperor and Adélie penguins, and numerous species of petrels, as well as hundreds of species of deep-sea invertebrates.
The Amundsen Sea Embayment, a region of sea ice and glacial ice, is a significant feature draining into the sea. It is a primary site of rapid ice melt on the West Antarctic Ice Sheet, contributing substantially to sea level rise in the 20th and 21st centuries. The Thwaites Glacier, which has the world’s widest glacial interface with the ocean, drains into the Amundsen Sea.
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Why is the Amundsen Sea important for studying climate change?
The Amundsen Sea is important for studying climate change because the Amundsen Sea Embayment, a part of the West Antarctic Ice Sheet (WAIS) that drains into the sea, experiences rapid ice melt and significantly contributes to sea level rise. The sea's temperature is affected by the upwelling of warm Circumpolar Deep Water (CDW), which accelerates ice loss from the Amundsen Sea Embayment. Additionally, the Amundsen Sea Low, a low-pressure region above the sea, influences precipitation, temperature, and ice melting in West Antarctica. This region has deepened due to increasing greenhouse gases, leading to cyclonic winds and reduced sea ice. The basin initially formed millions of years ago and became covered in ice around 27 million years ago. Today, the embayment contains 20% of the ice sheet’s total volume.
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Amundsen Sea, arm of the Southern Ocean adjoining West Antarctica south of about 70° S latitude, bordered on the west by Cape Dart on Siple Island and on the east by Cape Flying Fish at the northwestern edge of Thurston Island (see also Antarctica). The sea also includes the ice-covered portion of the coast of Marie Byrd Land called the Amundsen Sea Embayment. The water body was first surveyed in February 1929 by Norwegian explorer Captain Nils Larsen, who named it after renowned Norwegian polar explorer Roald Amundsen.
The Amundsen Sea hosts a variety of wildlife, though at low densities. Marine mammals present in the sea include crabeater seals, minke whales and fin whales (see also rorqual), and killer whales (orcas). The sea also serves as habitat for seabirds (such as emperor and Adélie penguins and multiple species of petrels) and hundreds of species of deep-sea invertebrates.
Formation and physiography
The basin first formed between 90 and 83 million years ago, toward the end of the Cretaceous Period, and portions became covered in ice starting roughly 27 million years ago during the Oligocene Epoch. In the present day, the most significant feature that drains into the sea is the Amundsen Sea Embayment, a region of sea ice and glacial ice that spans a 123,600-square-mile (320,000-square-km) portion of the West Antarctic Ice Sheet (WAIS), which also contains 20 percent of the ice sheet’s total volume. The Amundsen Sea Embayment, which includes portions of the Thwaites Glacier, is important for being one of the primary sites of rapid ice melt on the WAIS, and it has served as a substantial contributor to sea level rise during the 20th and 21st centuries(see also global warming).
Climate and hydrology
The temperature of the Amundsen Sea typically falls between 30 and 35 °F (–1.1 and 1.7 °C). Historically, the Amundsen Sea was cooler than it is now, and much of the sea’s modern warming can be explained by wind patterns generated by a region of low pressure that sits above the sea called the Amundsen Sea Low. The depth (and strength) of this region varies seasonally, and its changes influence precipitation, evaporation, temperature, and ice melting in West Antarctica. The Amundsen Sea Low has deepened overall since the 1970s, because of the enhanced heat-trapping effect caused by rising levels of greenhouse gases in the atmosphere; and this process has increased cyclonic winds that drive reductions in sea ice.
The sea’s temperature is also affected by the upwelling of the warm water mass called the Circumpolar Deep Water (CDW), which is a component of the Antarctic Circumpolar Current, near the edges of the continent. The first attempts to map the Amundsen Sea’s circulation took place in 1994, and they revealed that upwelling of the CDW also warms the base of the ice sheet, which accelerates the loss of ice volume from the Amundsen Sea Embayment.