Ice sheet dynamics
= Ice sheet dynamics
{wiki}
<Ice sheet dynamics> combines mass conservation with the forces driving and resisting ice flow. For thickness $H$ and depth-integrated horizontal flux $\mathbf q$, a simple fixed-bed budget is $\partial_tH+\nabla\cdot\mathbf q=a$, where $a$ is net accumulation in ice-equivalent units. A local increase in thickness can therefore come from accumulation or convergent transport.
Surface slopes supply gravitational driving stress, resisted by internal deformation, <basal sliding> laws and lateral or longitudinal stresses. The <shallow-ice approximation> and <shallow-shelf approximation> retain different balances. Near a <grounding line>, flotation and contact with the bed must be included when connecting an inland ice sheet to an <ice shelf>.