Current trends in the ice thickness and concentration on the waterways of the arctic

Abstract

The current trends in the change in the ice cover thickness and concentration along the Arctic waterways are investigated. For the vessels following these routes, the dynamics of changes in the probabilities of occurrence of ice exceeding the maximum ice class characteristics in different seasons was determined using the example of the most difficult sections of the Northern Sea Route – the Sannikov and Vilkitsky straits. As the initial data on the ice cover, the results of GLORYS12.v1 reanalysis, previously verified using satellite monitoring data and archived information from polar stations were used. The application of reanalysis is substantiated by the fact that the methods of monitoring of changes in the ice conditions have limitations in terms of discreteness of observation of a specific section of the water area. Validation of the reanalysis results for the Vilkitsky and Sannikov straits confirmed their compliance with the actual observations. Therefore, this reanalysis is used as a source of factual material on the average daily values of concentration and thickness of the ice cover in various parts of the water areas of the straits. Data processing and trend detection were carried out using the traditional statistical methods. It was found that for the period from 1993 to 2018, in both straits, there was a monotonous decrease in the probability of occurrence of ice cover with characteristics exceeding the permissible ice class limits. Similar trends were identified in other Arctic waters, which confirms the possibility of expansion of the navigation period on the Arctic routes. However, starting from 2009-2012, in the summer months, an increase in the ice thickness and concentration was observed due to deterioration in navigation conditions. Reasons for the phenomenon are suggested. Despite the general improvement in the navigation conditions in the Arctic, the appearance of opposite trends confirms the relevance of further development of the icebreaker fleet.