27 
Pomeranian Bay average —A— Pomeranian Bay max. 
Szczecin Lagoon average —■— Szczecin Lagoon max 
Mild Moderate Strong 
Figure 2.10. Thickness of level ice in Szczecin Lagoon and Pomeranian Bay in different ice 
winter classes 
As it has been pointed out earlier (page 12), only some average ice parameters are suitable for 
comparing ice winter classes. For example, there are no essential differences in the dates of 
first ice appearance in mild, moderate or strong ice winters. However, the occurrence of first 
ice in early December (or already in November) does not automatically indicate a strong 
winter. The other ice parameters under consideration, especially the number of days with ice, 
duration of ice season and maximum thickness of level ice differ clearly for each ice winter 
class. 
Finally, in table 2.10 the important characteristics of three ice winter classes are presented, 
valid for the areas of Szczecin Lagoon and Pomeranian Bay. 
Table 2.10. Characteristics of ice winter classes in the areas of Szczecin Lagoon and Pomeranian Bay 
Ice class 
Area of ice 
occurrence 
Duration of ice 
occurrence 
average ± st.dev. 
Ice thickness 
[cm] 
average ± st.dev. 
Ice concentration 
min average max 
Szczecin Lagoon 
4 weeks 
2,5 weeks 
10 
6 
1/10 
6/10 
8/10 
Mild 
Pomeranian Bay 
3 days 
3 days 
3 
2 
- 
1/10 
3/10 
Szczecin Lagoon 
8 weeks 
3 weeks 
20 
7 
4/10 
8/10 
10/10 
Moderate 
Pomeranian Bay 
3 weeks 
2,5 weeks 
13 
9 
1/10 
3/10 
8/10 
Strong to 
Szczecin Lagoon 
14 weeks 
3 weeks 
40 
15 
5/10 
10/10 
10/10 
extremely 
strong 
Pomeranian Bay 
6 weeks 
3 weeks 
32 
13 
3/10 
8/10 
10/10