Limitation of visibility on the coast of the Kara Sea in the context of modern climate change

An analysis of standard meteorological observations of horizontal visibility was performed, based on instrumental and visual observations at two Russian meteorological stations located on the southern coast of the Kara Sea. Horizontal visibility is an important navigation criterion for choosing safe routes and speeds along the Northern Sea Route. A decrease in horizontal visibility to less than 50 m is a dangerous weather event. The study of the conditions for the occurrence of such a dangerous phenomenon has become especially relevant when using giant ice-class tankers, the length of which reaches 300 m. The analysis showed that the frequency (probability) of unfavorable conditions for horizontal visibility has a pronounced seasonal variation. A relationship was found between the increase in frequency and changing climatic conditions, namely an increase in frequency against the background of modern global warming which is expressed both in a steady increase in surface air temperature in all seasons of the year and in a reduction of sea ice cover in the summer.