Assessing small-scale deformation and stability of landfast sea ice on seasonal timescales through L-band SAR interferometry and inverse modeling

Abstract

Rapid environmental change and increases in use of shorefast ice by industry and coastal communities highlight the need for an approach to accurately assess landfast sea-ice stability on seasonal timescales. While stability can sometimes be inferred from field measurements, current methods are lacking robustness and the ability to be automated and applied over large areas and long time scales to ensure safety and document change in the context of transportation, indigenous ice uses and industrial development. This paper introduces an inverse model capable of reconstructing three-dimensional deformation fields from one-dimensional interferometric L-band Synthetic Aperture Radar (SAR) phase patterns. We apply this method at three landfast ice locations on the Alaska Beaufort Sea coast near Barrow and Prudhoe Bay. We find the small-scale displacements estimated from the model consistent with regional patterns of ice motion. Our study suggests that interferometry can provide planning and decision-support information for ice road development and structures operating within ice. Moreover, InSAR can potentially increase our understanding of sea ice on a fundamental level in terms of large-scale stability and long-term changes in ice dynamics.