C-band SAR observations of marginal ice zone rheology in the Labrador Sea

Synthetic-aperture radar (SAR) imagery collected during the LIMEX´87 field program in the Labrador Sea is used to qualitatively interpret the deformation modes in play throughout the experiment. The ice cover exhibited two distinct rheologies separated by a clear line of shear: a nonlinear viscous outer regime, and a quasi-brittle inner regime. A single constitutive relation capable of effectively modeling both is unlikely within a plastic rate-independent formulation. Rate-dependent effects are discussed in relation to favoring brittle fraction in an otherwise ductile material