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Secrets of the St. Lawrence

The four seasons - Vessel icing

Among the pleasures that winter has to offer is freezing rain, which covers everything, including windshields, in an icy glaze. At sea, these conditions can quickly become dangerous.

Weight of the ice

In the Gulf and on the River, there is a risk of vessels icing as soon as the air temperature falls below -2 °C.

Icing is caused by spray thrown up from the hull and by the wind onto the vessel's superstructure, once the wind reaches about 40 knots.

Several tonnes of ice can accumulate within a few hours, causing the vessel to capsize or even sink.

Marine warnings are issued automatically whenever there is a risk of significant icing. Freezing sea spray occurs from November to April in ice-free areas.

A container ship is almost completed enveloped in thick white ice due to freezing sea spray that has frozen to the exterior.

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