Does the Baltic Sea freeze over in winter?

Does the Baltic Sea freeze over in winter?

According to scientific research, the Baltic Sea has frozen many times in the past. The earliest records of freezing date back to the era of the Vikings, who traveled on the frozen sea. In the Middle Ages, freezing of the Baltic Sea was a common phenomenon that significantly affected trade and communication between the Baltic states.

In the 16th and 17th centuries, the freezing of the Baltic Sea reached its peak. It was common for the ice to cover the entire sea, creating a solid surface that made it possible to travel on foot, by cart and even on horseback. This was an unusual phenomenon that attracted the attention of both locals and travelers from other parts of Europe.

The freezing of the Baltic Sea has been recorded several times in recent decades, with the most notable events occurring in 1987, 1996 and 2010. During these periods, ice covered much of the sea, making navigation difficult and affecting seaport operations

Ice formation in the Baltic Sea begins along the coasts of the northern Gulf of Bothnia and the inner Gulf of Finland. This usually happens in late October and early November. The freezing then spreads to the Quark, the open Gulf of Bothnia and the coasts of the Bothnian Sea. In normal winters, ice also covers the rest of the Bothnian Sea, the Archipelago Sea, the entire Gulf of Finland and part of the northern Baltic Proper.

In mild winters, the Bothnian Sea does not freeze at all, and the Gulf of Finland is covered by ice only partially. In harsh winters, the ice reaches the Gulf of Denmark and the central part of the Baltic Proper. The last area to freeze is northeast of Bornholm in the southern Baltic Sea.

The melting season begins in April and progresses from south to north. In the northern part of the Baltic Proper, the ice disappears in early April. In early May, ice remains only in the northern Gulf of Bothnia, where the last bits of ice also melt in early June.

The Polish ports of Gdansk, Gdynia, Swinoujscie and Szczecin are „ice-free”. Even if an ice cover forms on the water’s surface, it is never thick enough to paralyze port operations. Only prolonged and severe frosts can cause ice to form, but during such periods port channels and basins are cleared by icebreakers.

Please visit below link for the latest ice report for the Baltic Sea,

Baltic Sea Icing Report

and particularly for the Polish coastline:

Polish coastline icing report

Sources: The Nautical Institute – London, Polish Institute of Meteorology and Water Management, Own elaboration; 

Satellite map of the Baltic Sea in winter
Baltic Sea in mild winter Source:NASA/Goddard Space Flight Center, and ORBIMAGE - → png


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