Holocene melting of the West Antarctic Ice Sheet driven by tropical Pacific warming

• Published in: Nature Communications
• Main Authors: Sproson, Adam D., Yokoyama, Yusuke, Miyairi, Yosuke, Aze, Takahiro, Totten, Rebecca L.
• Format: Text
• Language: English
• Published: Nature Publishing Group UK 2022
• Subjects: Article; Amundsen Sea; Antarctic; Pacific; The Antarctic; West Antarctic Ice Sheet; West Antarctica; Antarc*; Antarctica; Ice Sheet; Ice Shelf; Ice Shelves
• Online Access: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9123186/; http://www.ncbi.nlm.nih.gov/pubmed/35595753; https://doi.org/10.1038/s41467-022-30076-2

The primary Antarctic contribution to modern sea-level rise is glacial discharge from the Amundsen Sea sector of the West Antarctic Ice Sheet. The main processes responsible for ice mass loss include: (1) ocean-driven melting of ice shelves by upwelling of warm water onto the continental shelf; and (2) atmospheric-driven surface melting of glaciers along the Antarctic coast. Understanding the relative influence of these processes on glacial stability is imperative to predicting sea-level rise. Employing a beryllium isotope-based reconstruction of ice-shelf history, we demonstrate that glaciers flowing into the Amundsen Sea Embayment underwent melting and retreat between 9 and 6 thousand years ago. Despite warm ocean water influence, this melting event was mainly forced by atmospheric circulation changes over continental West Antarctica, linked via a Rossby wave train to tropical Pacific Ocean warming. This millennial-scale glacial history may be used to validate contemporary ice-sheet models and improve sea-level projections.