To what extent is there a mechanical coupling between Antarctic ice-shelves and sea-ice?

• Main Author: Freer, Bryony
• Format: Other/Unknown Material
• Language: English
• Published: University of Canterbury 2019
• Subjects: Antarctic; Erebus Glacier; Erebus Glacier Tongue; Mertz Glacier; Sulzberger Ice Shelf; The Antarctic; Wilkins; Wilkins Ice Shelf; Antarc*; Ice Sheet; Ice Shelf; Ice Shelves; Iceberg*; Sea ice
• Online Access: http://hdl.handle.net/10092/18560

Understanding the causes of recent trends in Antarctic ice shelves and sea ice is crucial for improving our modelling capabilities to predict the future state of the Antarctic Ice Sheet and its future contribution to sea level rise. An overlooked component of this is the direct interaction between ice shelves and sea ice; two systems which have traditionally been studied rather separately. This report closely examines the literature surrounding this, and suggests that current evidence points to the existence of a tight mechanical coupling, in which the behaviour of both sea-ice and ice-shelves is able to influence the stability of the other. Examples are used to illustrate this interaction, including the recent Larsen A, B and Wilkins Ice Shelf collapses, major calvings from the Erebus Glacier Tongue and Sulzberger Ice Shelf, and sea ice trends in the MIZ at the Ninnis-Mertz glacier system. In particular, sea-ice is shown to be able to dampen certain (but not all) types of ocean waves, reducing their destructive force on ice shelves. Grounded icebergs from ice shelves have also been observed to form centres of extended sea-ice formation. However, current models contain insufficient parameterisation of this coupling, limiting their accuracy, and so further research to understand and quantify its nature and extent for model input is highly recommended.