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On the basis of frequency distribution of the accumulated areal ice volume, the 30 ice winters 
under consideration were divided into three ice winter classes. The most ice winters in the 
same class obey the same typical feature, however the large dispersion of the ice parameters is 
reflected in relatively large values of standard deviations. There are also some ice winters 
with extreme parameters (critical cases) which show characteristics of both mild and 
moderate ice classes. In this case, a critical analysis of the observation data is advisable. The 
border between the moderate and strong ice winters is well defined. 
For the classification of the ice winters in the Southern Baltic, similar investigations of the ice 
data from all observation stations are required. Except critical cases, the accumulated areal ice 
volume seems to be useful parameter for the definition of the ice winter severity types.