Abstract

Sea-ice floating upon the Arctic ocean is a constantly moving, growing, and melting surface. The seasonal cycle of sea ice volume has an average change of 10,000 Km^3 or 9 billion tonnes of sea ice. The role of dynamic redistribution of sea ice, the process by which it flows and deforms when blown by winds and floating upon ocean currents, is responsible for distribution of thicker multi-year ice and has high interannual variability. Due to the rheology of sea-ice, when drifting and deforming, positive divergence is more likely than negative, with a greater area of leads than ice ridges. The formation of leads in winter months exposes the open ocean to the cold atmosphere causing the rapid formation of new ice.

Here we investigate the role of dynamics processes within Artic sea ice using both observational and modelling studies. We combine satellite-derived observations of sea ice concentration, drift, and thickness to provide maps if ice growth, melt and dynamic redistribution. Ten winter growth and summer melt seasons are analysed over the CryoSat-2 period between October 2010 and April 2020. We extend this analysis to future scenarios by looking at the modelled dynamics of Arctic sea-ice in CMIP6 models. These models allow us to consider the changing role of sea ice divergence within a rapidly changing Arctic.