Ice cover of the Russian Arctic seas along the Northern sea route in the current climatic period

The paper considers the ice cover in the Arctic seas of the Northern Sea Route (NSR): Kara, Laptev, East Siberian and Chukchi since 1946. A comparison of the long-term course of integral average annual air temperature anomalies and seasonal average ice cover anomalies allows identifying a year 2005, starting from which the sea ice cover sharply decreases in a good agreement with the increase and accumulation of positive air temperature anomalies. The researchers reveal that the average level of ice cover has decreased by 1.7 times since 2005, however, the values of the range of fluctuations and standard deviation have remained almost unchanged, i.e. ice cover fluctuates in the same range, but at a lower average level. The main shipping routes are cleared about three decades earlier. The repeatability of complete cleansing of the seas has increased to 60—90%.