“…The appropriate averaging scales (about 400 km and 5.5 months for winter conditions) were found small enough to clearly separate the interannual variability of the mean circulation from the fluctuating motion due to passing atmospheric perturbations, local oceanic eddies and inertial and tidal motion. This approach, based on the analysis of single particle trajectories, has been widely used to study diffusion properties of Lagrangian drifters in the ocean (see, e.g., Zhang et al, 2001;Poulain and Niiler, 1989) and is now becoming a standard analysis tool for sea-ice dynamics (Lukovich et al, 2011(Lukovich et al, , 2015Gabrielski et al, 2015).…”