The Baltic Sea and Winter Time Maritime Transportation

Ice Code, which was updated for the last time in 1981 (WMO, 1989 SMHI, 1981 Koslowski, 1981 SMHI, 2002) and is still valid today. 

Observation Lat/N Long/E Winters with Ice Occurrence Occurrence Days with 

Areas of Observation Lat/N Long/E No. of Winters No. of Winters with Ice Freq. of Ice Occurrence Dates of Ice Occurrence Days with Ice Max. Ice Thickness 

FIGURE 8.2 Main flow of maritime transport in the Baltic Sea. (See color plate) 

In the 1920s and 1930s, new, more effective icebreakers were put into service, but the volume of maritime transport during the winter months stayed rather low. 

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