Deformation - induced melting in the margins of the 1 West - Antarctic ice streams

Flow of glacial ice in the West Antarctic Sheet localizes in nar-3 row bands of fast flowing ice streams bordered by ridges of nearly stagnant 4 ice, but our understanding of the physical processes that generate this mor-5 phology is incomplete. Here, we study the thermal and mechanical proper-6 ties of ice-stream margins, where flow transitions from rapid to stagnant over 7 a few kilometers. Our goal is to explore under which conditions the intense 8 shear deformation in the margin may lead to deformation-induced melting. 9 We propose a 2D model that represents a cross-section through the ice-stream 10 margin perpendicular to the downstream flow direction. We limit temper-11 ature to the melting point to estimate melt rates based on latent heat. Us-12 ing rheology parameters as constrained by laboratory data and observations, 13 we conclude that a zone of temperate ice is likely to form in active shear mar-14 gins.