A STATISTICAL ANALYSIS OF SPATIAL STRENGTH HETEROGENEITY OF SEA ICE COVER

摘要

Data published recently show that the ice strength in the same field varies significantly. Spatial strength heterogeneity of the ice cover was found in the field measurements of ice strength in different sites in the world: Spitsbergen, The Far East of Russia and the Gulf of Ob. In most cases the small scale heterogeneity has been extensively studied (sizes of an ice field were smaller or equal to 180 m by 180 m) and seems to be a suitable research object. The investigations of the ice strength spatial heterogeneity in first-year level ice in several regions have been done in this study. Statistical analysis of field data of the ice strength distributions was performed. The analysis consisted in calculation of the main probabilistic parameters of the ice strength distribution and determination of the theoretical distribution law fitting the experimental data. The goal of the work was to determine the strength frequency. The ratio of field area A_i corresponding to the ice strength R_(ct) to total area A_(total) of ice field was revealed to characterize the strength frequency and the probability of the strength R_(ct). Several theoretical distributions (normal, lognormal, gamma, Weibull and Generalized beta) of the strength frequency for fields in different seas were chosen and compared.