Interannual variation of modified Circumpolar Deep Water volume in the Dotson-Getz Trough, West Antarctica

• Main Authors: Kim, T., Yang, H., Kim, Y., Yoo, J., Park, J.
• Format: Conference Object
• Language: English
• Published: 2023
• Subjects: Amundsen Sea; Austral; Dotson Ice Shelf; Dotson-Getz Trough; Getz; West Antarctica; Antarc*; Antarctica; Ice Shelf; Ice Shelves
• Online Access: https://gfzpublic.gfz-potsdam.de/pubman/item/item_5016716

In recent decades,wide-spread thinning of ice shelves in the Amundsen Sea has been recorded driven by basal melting. Relatively warm modified Circumpolar Deep Water (mCDW) flows onto the continental shelfand fills the Dotson-Getz Trough (DGT) and reaches the base of the Dotson Ice Shelf (DIS). Long-term hydrographic data (2007–2018) for the DGT were obtained during seven oceanographic surveysto study the interannual variation in mCDW volume and properties in the DGT and their causes. Although the mCDWvolumeshowed relatively weak interannual variations at the entrance of the DGT, these variations intensified in front of the DIS. There, the mCDW volume was ~8 × 10 3 km 3 in 2007, rapidly decreased to 4.7 × 10 3 km 3 in 2014 before rebounding to 7.3 × 10 3 km 3 in 2018.Such interannualvariabilityappears to result from localEkmanpumping along the DGT, with the dominant south-southeast wind modulating the amplitude of Ekman upwelling along the eastern boundary of the Amundsen Sea polynya during the austral summers of the surveyed years. We note a strong correlation between the wind variability and the longitudinal location of the Amundsen Sea Low.