Wave induced fracture probabilities for arctic sea-ice

Techniques for the numerical simulation of ice-coupled wave scattering by variations in ice thickness have progressed to a stage that the prediction of wave decay within long swathes (∼ 1600 km) of natural sea-ice is possible. In this work we determine how decay rates may be used with random linear wave theory to estimate the propensity of waves to fracture the ice cover. Given an incident wave spectrum and a fracture strain, we show how the probability of cracking may be found as a function of distance from the ice edge. Choosing a definitive critical probability for the limit of fractured sea-ice allows the time-evolution of the size of the region of cracked sea-ice to be explored, and this is done for 2008 using WAVEWATCH III™ hindcasts. By this means, estimates of the probability for waves to crack ice could potentially be incorporated into ice/ocean models and oceanic global circulation models (OGCMs), where it is believed that the assimilation of such physics is an important factor for increasing accuracy.

Research highlights
► Employs decay rates for ice-coupled waves from a model using Arctic sea ice data.
► Wave induced strains are estimated using random linear wave theory.
► The width of the breakup zone is estimated by using a failure criterion.
► How the broken up zone responds to changes in sea-state can be determined.
► Future wave induced ice breakup is likely to be more extensive.