How Has the Ferrel Cell Contributed to the Maintenance of Antarctic Sea Ice at Low Levels From 2016 to 2022?

• Published in: Geophysical Research Letters
• Main Authors: Shaoyin Wang, Jiping Liu, Zixin Wei, Dongxia Yang, Hua Li, Suoyi Ding, Fengming Hui, Xiao Cheng
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2024
• Subjects: Antarctic Sea ice; Ferrel cell; mid‐latitude wave pattern; precipitation; La Niña; hydrological cycle; Geophysics. Cosmic physics; QC801-809; Antarc*; Antarctic; Sea ice
• Online Access: https://doi.org/10.1029/2024GL108801; https://doaj.org/article/7b9c9685188745a48235b1374ab17046

Abstract This study investigates the specific circulation anomalies that have sustained the low Antarctic sea ice state since 2016. Firstly, we find a significant strengthening and southward shift in the Ferrel Cell (FC) during 2016–2022, resulting in a marked increase in southward transport of heat and moisture. Secondly, this enhanced FC is closely associated with a stronger mid‐latitude wave pattern. This pattern is zonally asymmetric and greatly amplifies the poleward advections of heat and moisture, leading to the increased downward longwave radiation, more liquid precipitation and sea ice retreat in specific regions, including the western Pacific and Indian Ocean sectors, Ross and northern Weddell Seas. The mechanism deduced from the short‐term period is further supported by the results of 40 ensemble members of simulations. The southward expansion of the FC and sea ice decline are closely linked to La Niña‐like conditions but may also be driven by anthropogenic global warming.