EGU General Assembly 2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

Antarctic ice-shelf advance driven by anomalous atmospheric and sea-ice circulation

Frazer Christie1, Toby Benham1, Christine Batchelor2, Wolfgang Rack3, Aleksandr Montelli1, and Julian Dowdeswell1
Frazer Christie et al.
  • 1Scott Polar Research Institute, University of Cambridge, Cambridge, CB2 1ER, UK (
  • 2School of Geography, Politics and Sociology, University of Newcastle, Newcastle, NE1 7RU, UK
  • 3Gateway Antarctica, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand

The disintegration of the eastern Antarctic Peninsula’s Larsen A and B ice shelves has been attributed to atmosphere and ocean warming, and increased mass losses from the glaciers once restrained by these ice shelves have increased Antarctica’s total contribution to sea-level rise. Abrupt recessions in ice-shelf frontal position presaged the break-up of Larsen A and B, yet, in the ~20 years since these events, documented knowledge of frontal change along the entire ~1,400-km-long eastern Antarctic Peninsula is limited. Here, we show that 85% of the seaward ice-shelf perimeter fringing this coastline underwent uninterrupted advance between the early 2000s and 2019, in contrast to the two previous decades. We attribute this advance to enhanced ocean-wave dampening, ice-shelf buttressing and the absence of sea-surface slope-induced gravitational ice-shelf flow. These phenomena were, in turn, enabled by increased near-shore sea ice driven by a Weddell Sea-wide intensification of cyclonic surface winds around 2002. Collectively, our observations demonstrate that sea-ice change can either safeguard from, or set in motion, the final rifting and calving of even large Antarctic ice shelves.

How to cite: Christie, F., Benham, T., Batchelor, C., Rack, W., Montelli, A., and Dowdeswell, J.: Antarctic ice-shelf advance driven by anomalous atmospheric and sea-ice circulation, EGU General Assembly 2023, Vienna, Austria, 24–28 Apr 2023, EGU23-3165,, 2023.