Generation of the Amundsen Sea Low by Antarctic Orography

• Published in: Geophysical Research Letters
• Main Authors: Goyal, R, Jucker, M, Sen Gupta, A, England, MH
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: American Geophysical Union (AGU) 2021
• Subjects: 13 Climate Action; Antarctic; Amundsen Sea; Antarc*; Antarctica; Sea ice
• Online Access: http://hdl.handle.net/1959.4/unsworks_79037; https://unsworks.unsw.edu.au/bitstreams/70fc4247-b978-46ba-96bf-689053436b3b/download; https://doi.org/10.1029/2020GL091487

The Amundsen Sea Low (ASL) is a distinctive feature of the Southern Hemisphere high latitude atmospheric circulation, regulating regional Antarctic climate, meridional heat transport, ocean circulation, and sea-ice in the Amundsen-Bellingshausen Seas. Most previous research on the ASL has focused on its variability with only a few studies attempting to understand why the climatological ASL exists. These studies have proposed different hypotheses to explain the presence of the ASL, however, a clear understanding of the mechanisms responsible for the generation of the ASL remains uncertain. Here we use an atmospheric general circulation model to show that the ASL is a consequence of the interaction between Antarctic topography and the westerly wind jet, with negligible influence from low-latitude teleconnections. A nonrotating fluid flow simulation further suggests that the ASL can be explained by flow separation resulting from the interaction of westerly winds with the topography of Antarctica.