May 13, 2015

Oceanic and atmospheric forcing of Larsen C Ice-Shelf thinning

Holland, P. R., Brisbourne, A., Corr, H. F. J., McGrath, D., Purdon, K., Paden, J., Fricker, H. A., Paolo, F. S., Fleming, A. H.
The Cryosphere
  • States that the collapses of Larsen A and B ice shelves on the eastern Antarctic Peninsula have caused their tributary glaciers to accelerate, contributing to sea-level rise
  • States that the surface of Larsen C Ice Shelf (LCIS), the largest ice shelf on the peninsula, is lowering
  • Hypothesizes that this could be caused by unbalanced ocean melting (ice loss) or enhanced firn melting and compaction (englacial air loss)
  • Derives separate estimates of ice and air thickness changes during a 15-year period using a novel method to analyze eight radar surveys
  • Finds that the uncertainties are considerable, but the primary estimate is that the surveyed lowering (0.066 ± 0.017 meters per year) is caused by both ice loss (0.28 ± 0.18 meters per year) and firn-air loss (0.037 ± 0.026 meters per year)
  • Results indicate that the ice loss is much larger than the air loss, but both contribute approximately equally to the lowering because the ice is floating