Ice formation processes in the Sea of ​​Azov

 

Extreme ice conditions were observed in the Sea of ​​Azov in the seasons of 1953–1954, 1968–1969, and 1971–1972. In the 21st century, the highest ice cover of the sea was recorded during the cold winters of 2002/2003, 2005/2006, 2007/2008, and 2011/2012 (Ginzburg et al., 2021). Several cases of freezing of the Kerch Strait are known. For example, in 1927 and 1977, it was possible to travel along the strait on sleds. Residents of Kerch recall that in the 60s of the last century, the strait froze almost every year, and in 1993, at 17 degrees below zero, an icebreaker worked to facilitate the movement of ferries across the crossing.

 

Modern global warming contributes to the "softening" of winters, changing the characteristics of the sea ice regime. According to A.A. Magayeva (SSC RAS, 2024), the average long-term ice cover of the Sea of ​​Azov for the period from 2000 to 2024 was 24.5%. This is lower than the average long-term ice cover for the period from 1991 to 2020 (27.1%, which is considered the climatic "norm") and lower than the average long-term value for the period from 1950 to 2024 (27.8%).

 

This year, when January turned out to be abnormally warm, on February 4-5, according to the Hydrometeorological Center of Russia, no ice was observed in the waters of the Sea of ​​Azov and the Taganrog Bay. The appearance of the first ice formations is observed since February 6, due to a decrease in air and water temperature with the influx of cold air masses into the basin of the Sea of ​​Azov.

 

As of February 25, 2025, active ice formation continued in the Sea of ​​Azov. About a third of the sea area (including the Taganrog Bay) was covered with ice.

 

In the Taganrog Bay, eastern and partially southeastern areas of the sea near the coast, fast ice (a type of stationary ice in bays and coastal areas of the sea) 10 cm thick, nilas (young ice in the form of a thin elastic ice crust up to 10 cm thick), gray ice (14 cm thick) and drift ice were observed. In the Temryuk area, in the south of the Taman Bay and in the north-eastern part of the Kerch Strait, thin ice of the initial types (flask, fast ice, nilas) was observed. In the central and southern parts of the Kerch Strait, as well as in most of the sea itself, clear water prevailed.

 

The inhabitants of the sea endure the ice period differently. The yellow plankton does not tolerate the cold: the comb jellies Beroe and Mnemiopsis, as well as the jellyfish Cornerot. With the onset of cold weather, they die.

 

Such heat-loving species as mullet, anchovy, singil, mullet, Don herring, Azov puzanok, horse mackerel, garfish go to winter in the "warm regions" of the Black Sea.

 

Mollusks are not afraid of the cold, such fish species as sturgeon, bream, pike perch, roach, turbot, successfully enduring harsh winters.

 

According to statistics, severe winters have become less frequent, and the ice period in the Sea of ​​Azov has significantly shortened. The final clearing of the sea from ice usually occurs in March. Most likely, this "custom" will not be broken in 2025, since according to weather forecasters, a significant warming will occur by the end of the first ten days of March.

 

Press service of VNIRO