Aug 2, 2017

Impacts of the Larsen-C Ice Shelf calving event

by
Anna E. Hogg, G. Hilmar Gudmundsson
,
Nature Climate Change
  • States that:
    • Loss of ice shelf mass can reduce the backward pressure blocking the downward flow of ice from the interior
    • On the Antarctic Peninsula, ice shelf thinning or collapsing events have caused up to an eight-fold speed-up in the rate of ice flow, increasing the ice-sheet contribution to global sea-level rise
  • States that:
    • Ice rises (isolated high-elevation topographic features overridden by the ice-shelf, e.g. small islands that serve as pinning points) provide additional buttressing support for floating ice-shelves
    • An ice shelf's loss of contact with an ice rise can prompt a significant acceleration in ice speed and possibly further destabilization of the ice front
  • Warns that if iceberg calving events unground the Larsen-C ice shelf from the Bawden ice rise, the remaining shelf will be much less stable
  • Notes that regardless, this is an opportunity for glaciologists to test their ideas about how ice shelves affect ice flow
  • Notes that it is not clear what physical mechanism drives ice-shelf disintegration, meaning a direct link to global climate change cannot be established, and so model predictions of the pace and onset of future collapse events are less reliable