![]() Glaciers terminating in temperate waters are frequently found to feature such underwater feet. Second, recent work on the breakup of icebergs due to hydrostatic stresses from a submerged ice foot (the “footloose” mechanism) prompts the question of whether a similar mechanism might operate at floating glacier fronts. In particular, a glacier on a sloped bed will experience an isostacy-driven upward deflection as it enters the water. First, recent observational results suggest an important role of buoyant flexure in glacier calving under certain conditions. Building on previous theoretical work by Reeh and Vaughan, we consider an idealized representation of the glacier-bedrock-ocean system, in order to maintain a level of simplicity that will yield new insight into the governing physical processes. While the majority of recent modeling studies focus on the appearance and propagation of crevasses as the glacier termini (or ice shelves) advance, we revisit the role of purely elastic bending stresses due to hydrostatic imbalances. ![]() Here we examine the role that elastic flexure plays in the calving of floating glacier termini. Interactions between glacier termini or ice shelf fronts and the ocean are therefore regarded as key processes in the dynamics of the cryospheric climate system: the presence or absence of a buttressing ice shelf can determine the stability of vast ice sheets, and the oceanic conditions at glacier termini are believed to be among the leading factors in setting glacier flow velocities and calving rates. Rising sea levels, increased ocean temperatures, changing surface albedo, and other positive feedback effects are expected to further increase the rates of melting and decay in the cryosphere. The accelerated disintegration of Antarctic ice shelves and the retreat of glaciers in all regions of the cryosphere are among the most consequential manifestations of a changing global climate. This work sheds light on the intricate processes involved in glacier calving and can be hoped to improve our ability to model and predict future changes in the ice-climate system. We find good agreement with observations. Our model provides theoretical estimates of the importance of each effect and suggests geometric and material conditions under which a given glacier will calve from hydrostatic flexure. We develop a mathematical model to account for the elastic deformation of glaciers in response to three effects: (i) marine and lake-terminating glaciers tend to enter water with a nonzero slope, resulting in upward flexure around the grounding line (ii) horizontal pressure imbalances at the terminus are known to cause hydrostatic in-plane stresses and downward acting torque (iii) submerged ice protrusions at the glacier front may induce additional buoyancy forces that can cause calving. Here we investigate the role of hydrostatic forces in glacier calving. This work sheds light on the intricate processes involved in glacier calving and can be hoped to improve our ability to model and predict future changes in the ice-climate system.Interactions between glaciers and the ocean are key for understanding the dynamics of the cryosphere in the climate system. ![]() ![]() Interactions between glaciers and the ocean are key for understanding the dynamics of the cryosphere in the climate system. ![]()
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