The role of sliding in ice stream formation

Ice streams are bands of fast-flowing ice in sheets. We investigate their formation as an example spontaneous pattern formation, based on positive feedbacks between dissipation and basal sliding. Our focus is temperature-dependent subtemperate sliding, where faster sliding leads to enhanced hence warmer temperatures, weak- ening the bed further, a similar feedback driven by melt water production. Using novel thermomechanical model, we show that steady fast slow flow can occur through downstream amplification noise conditions. This process lead establishment clearly defined stream separated from slowly flowing, cold-based ridges narrow shear margins. model also able predict widening due heat transport these downward advection cold induced accelerated primary stabilizing mechanism suppress steam altogether, give approximate, analytical criterion for formation.