The Arctic sea-ice cover: Fractal space-time domain

The temporal characteristics of the sea-ice motion were analyzed using the GPS-monitoring carried out during a drift of the ice camp "North Pole 32" in 2003. The detected accelerations of the ice field were found to be correlated in time. The energy release due to impact interactions between ice fields is distributed in accordance with a power law function. A relatively high value of its exponent (b similar or equal to 1.3) as compared to similar b-value for earthquakes (b similar or equal to 0.9) signalizes a high level of conservation in the sea-ice cover system and, correspondingly, low localization of spontaneous fracture events. The field observations were supplemented with the study of ice-cover fragmentation using the remote technique. The analysis of satellite images confirmed the uniform character of fracture at various scale levels and fractal geometry of crack-and-lead pattern. The spatial fractal dimension is not universal: it responses to the large-scale perturbations in sea-ice cover accompanied with the change of energy conservation. The shown time and length invariance in this permanently fracturing-restoring structure characterizes the Arctic sea-ice cover as a self-organized criticality system. (c) 2005 Elsevier B.V. All rights reserved.