The Influence of Platelet Ice and Snow on Antarctic Landfast Sea Ice

Sea ice fastened to coasts, icebergs and ice shelves is of crucial importance for climate- and ecosystems. Near Antarctic ice shelves, this landfast sea ice exhibits two unique characteristics that distinguish it from most other sea ice: \n1.Ice Platelets form and grow in super-cooled water, which originates from ice shelf cavities. The crystals accumulate beneath the solid sea-ice cover and are incorporated into the sea-ice fabric, contributing between 10 and 60% to the mass of the land-fast sea ice around Antarctica. \n2.A thick and partly multi-year snow cover accumulates on the fast ice, altering the sea-ice surface and affecting the sea-ice energy and mass balance. In order to investigate the role and the spatial and temporal variability of platelet ice and snow for Antarctic fast ice, we perform regular field measurements on the land-fast sea ice of Atka Bay as part of the international Antarctic Fast Ice Network (AFIN). Here we present the results of our observations in 2010 and 2011.