Winter shipping in Sweden and Finland

Shipping is an important engine for Swedish and Finnish industry. All of Finland's ports are ice-bound in winter, while Sweden has the longest coastline in Europe and every year ships and ferries transport more than 130 million tonnes of goods and 30 million people to and from Swedish ports. Finland should be regarded as an island with an economy that is dependent on shipping. In Finland the maritime cluster employs more than 50,000 people.
Around 90 percent of all Finnish and Swedish imports and exports travel by sea. This figure is expected to increase because maritime transport is efficient, safe and climate-friendly. So when winter closes in, it is important to be able to guarantee that ships can reach Finnish and Swedish ports by providing an efficient, reliable climate-friendly all-year icebreaking service.

Historical overview

In Sweden and Finland, icebreaking has been taking place since the end of the 19th century. Before that, the Baltic Sea and the west coast were not navigable in severe winters from late autumn through to the thaw in May. This meant that large parts of the Swedish and Finnish fleets, which consisted mainly of wooden ships, were in port for much of the year. The first icebreakers were privately owned. Later some local authorities also bought icebreakers to keep individual ports, such as Gothenburg, Malmö, Gävle, Norrköping, Stockholm, Turku and Luleå, free from ice obstacles during the winter. The first state-owned icebreaker, the Atle, was delivered in 1926 by Lindholmens shipyard in Gothenburg. This was followed by the Ymer from Kockums in Malmö in 1932. These two icebreakers made winter shipping in Sweden possible, although many ports still had to close during parts of the year. In Finland the first state icebreakers were built already in 1890’s.
It was not until 1953 that the Swedish icebreaker fleet was expanded with the addition of the Thule from the naval shipyard in Karlskrona. This represented a significant increase in Sweden’s icebreaking capacity. However, when the Atle was due to be withdrawn from service, the authorities realised that there was still a need for further new ships and in 1957 the Oden was delivered. She was a sister to the 1954 completed Finnish four-screw Voima, that replaced the biggest icebreakers lost due to the war. Unlike all the previous icebreakers, it was supplied by Wärtsilä in Helsinki. When industrial production began expanding in northern Sweden in the 1960s, a process very similar to today’s investments in battery production and fossil-free steel, the most important consideration was access to coal. Since it was impossible to meet the demand for coal from industry by stockpiling it, supplies had to be guaranteed all year round, which meant supplying it by ship in winter.

The first state-owned icebreaker, the Atle, was delivered in 1926 by Lindholmens shipyard in Gothenburg.

Icebreaker and Iceberg

Therefore, it was the import of coal and not the export of steel that drove the demand for winter shipping, although both ore mining and forestry industries began to experience competition from other producer countries and needed be able to deliver their products all year round more competitively than in the past, when large stocks were maintained on the continent. Winter shipping began as a local campaign in Luleå, but it soon became a national concern and a key issue for Swedish businesses. In August 1971, a report was issued by the port commission which highlighted the economic benefits of winter shipping for the important ports in northern Sweden. This was when the icebreakers in the Atle class – the Atle, the Ymer and the Frej – were supplied. Together with the Ale, which was originally built to break ice in the Trollhätte canal leading to Lake Vänern, and the Oden, which was delivered in 1989, they make up Sweden’s current icebreaker fleet. The fleet of five ships has had Luleå as its home port since the early 2000s. Today it ensures that the 50-year-old tradition of keeping Sweden open for winter shipping is maintained.
Finland invested a lot in new industries in the North at the end of the 1960’s and the nations built a joint series of 12.000 hp icebreakers of Tarmo, Varma, Apu, Tor and Njord, which helped in keeping the traffic to the northern ports open since 1971. The development and increase of vessel sizes, however, required to build even larger and more powerful icebreakers, which led to the creation of the Atle/Urho class in 1974-77.

Winter shipping as an operational assignment

In Sweden and Finland, the Swedish Maritime Administration and the Finnish Transport Infrastructure Agency are responsible for winter shipping and for keeping the ports open all year round. Their responsibilities include breaking ice at sea and assisting ships that have problems reaching ports. The icebreakers also provide help to merchant vessels by monitoring, directing, guiding and towing them. The icebreakers operated by the Swedish Maritime Administration and the Finnish Transport Infrastructure Agency assist ships in Swedish and Finnish coastal waters and on the sea routes between open water at sea and the fairways that are protected from sea ice, drift ice, pack ice and similar ice obstacles.
The climate of the Nordic region means that icebreaking is needed for almost half of the year to ensure that winter shipping is possible, regardless of what the winter weather is like. In mild winters, icebreaking is required only for ships travelling to the north of Baltic sea, but statistics show that there is likely to be a severe winter in Baltic sea every four years and then icebreaking is required all the way down to the southern Baltic Sea, in the Sound and along the west coast. To understand the extent of the icebreaking, it is important to be aware that almost 100,000 square kilometres of Baltic sea waters are covered with ice in a mild winter. In a normal winter, the area of ice is almost double this size and, in a severe winter, the entire Baltic Sea can be ice-bound, along with parts of the Kattegat and Skagerrak. In addition to the Gulf of Bothnia Finland has an additional challenge of the Gulf of Finland, which is also freezing.
Because the severity of the winters varies, the icebreakers have to be flexible. For example, the winter of 2019/2020 was very mild and the ice covered an area of only 37,000 square kilometres, which was a new minimum record since the beginning of the 20th century. As a result, only 140 vessels were helped in Swedish fairways, which was a very small number compared with the record winter of 1986/1987, when 4107 ships needed assistance and 771 were towed. The Swedish Maritime Administration has five icebreakers of its own and, if necessary, hires in external resources. The long-term, friendly cooperation with Finland and the international agreements ensure that the available resources are used efficiently. Finland has eight icebreakers owned and operated by the fully state-owned company Arctia. The oldest is the in 1954 commissioned and two timres modernized Voima, the Atle-class icebreakers Urho and Sisu from 1975-76, Otso and Kontio from 1986 and 1987, the multipurpose icebreakers Fennica and Nordica from early 1990’s and Polaris from 2016. Arctia has long term service contracts with the Finnish Transport Infrastructure Agency and the Agency occasionally also charters in other units from the market, typically powerful tugboats.
During the current season, the Swedish Maritime Administration and the Finnish Transport Infrastructure Agency are issuing restrictions for ships that are planning to operate in ice-covered waters. Only ships that meet the size and ice class requirements are eligible for assistance from icebreakers. The ice classification used is a Swedish-Finnish standard, which divides the ice into extremely difficult, difficult, moderately difficult, easy and very easy ice conditions.

Stena Arctica Crew Ice
Stena

Ice class: For operations in: Ice thickness:
1A Super Extremely difficult ice conditions > 100 cm
1A Difficult ice conditions > 50 cm
1B Moderately difficult ice conditions 30 – 50 cm
1C Easy ice conditions 15 – 30 cm
II Very easy ice conditions 10 – 15 cm

1A Super
1A
1B
1C
II

Extremely difficult ice conditions
Difficult ice conditions
Moderately difficult ice conditions
Easy ice conditions
Very easy ice conditions

>  100 cm
>  50 cm

30 – 50 cm
15 – 30 cm
10 – 15 cm

Icebreaking from a climate perspective

During the period of just over 120 years since icebreaking began in the Nordic region, the conditions and, importantly, the prospects for icebreaking in the future have changed.

Icebreaker Atle
Sjöfartsverket

On the Swedish side, the Swedish Meteorological and Hydrological Institute (SMHI) works closely with the Swedish Maritime Administration. With the help of the SMHI’s satellite images, reports from the icebreakers and from other ships and helicopter reconnaissance flights, ice maps are produced to allow the behaviour of the ice to be closely monitored. The same takes place in Finland by the Finnish Meteorological Institute’s Ice Service in co-operation with their colleagues at SMHI. After a series of mild winters in the 1990s and, in particular, the very mild winter of 2020, many people are probably wondering whether winter shipping will cease to be a problem in future as a result of climate change. Will icebreakers be needed at all in the Baltic Sea in the future? This is an important question, especially as icebreakers have a service life of up to 60 years. But even if climate change and our impact on the planet result in global average temperatures rising, this does not necessarily mean that the ice around our coasts will disappear either in the short or the long term. On the contrary, climate change may lead to increased pressure on the icebreakers to safeguard winter shipping. In low pressure conditions, with higher temperatures and wind, the ice becomes more thickly packed and when the temperature fluctuates, thick layers of pack ice and long slush belts form, which makes conditions more difficult and increases the need for icebreaking.
The longer-term climate models that predict the extent of the ice in the Baltic Sea also come to the conclusion that icebreaking will be needed for a long time to come. Assuming that the average temperature in the Nordic countries rises by three degrees over this century, it is estimated that the Baltic Sea will only be free of ice in one winter in every 17. Although a temperature increase of this kind would have a variety of different effects on winter shipping, icebreakers will definitely still be needed. Climate change and the growing awareness of the environmental impact of maritime transport have also resulted in the shipping industry being required to meet stricter environmental standards. This means that many of the international merchant ships which visit Swedish and Finnish ports have engines designed for open water and not for ice, which further increases the need for icebreakers for winter shipping. At the same time, the icebreakers themselves have changed. In the past they had diesel engines and now they run on LNG. In the future, there will be opportunities to use even more modern and climate-smart propulsion systems.
Therefore, it was the import of coal and not the export of steel that drove the demand for winter shipping, although both the ore mining and forestry industries began to experience competition from other producer countries and needed be able to deliver their products all year round more competitively than in the past, when large stocks were maintained on the continent. Winter shipping began as a local campaign in Luleå, but it soon became a national concern and a key issue for Swedish businesses. In August 1971, a report was issued by the port commission which highlighted the economic benefits of winter shipping for the important ports in northern Sweden. This was when the icebreakers in the Atle class – the Atle, the Ymer and the Frej – were supplied. Together with the Ale, which was originally built to break ice in the Trollhätte canal leading to Lake Vänern, and the Oden, which was delivered in 1989, they make up Sweden’s current icebreaker fleet. The fleet of five ships has had Luleå as its home port since the early 2000s. Today it ensures that the 50-year-old tradition of keeping Sweden open for winter shipping is maintained.

Therefore, it was the import of coal and not the export of steel that drove the demand for winter shipping…

Aurora Spirit
Wärtsilä

Finnish-Swedish cooperation

In the 1970s, when winter shipping became possible in the northern part of the Gulf of Bothnia and both Finnish and Swedish ports could be reached, the foundations were laid for the long-term, friendly cooperation between Sweden and Finland on winter shipping. Long before that, Finland and Sweden had worked together to develop icebreakers, but the 1970s saw the beginning of the two countries’ collaboration on operations. From the start, this was based on the practical need to help one another and share information. Today, the two nations use joint reporting on weather and ice conditions, have assistance services that work together and step in to help each other when needed. However, there is a striking difference between the crews of Swedish and Finnish icebreakers.
In 2020, the Finnish Transport Infrastructure Agency and the Swedish Maritime Administration signed a new cooperation agreement, which marked a milestone in Swedish-Finnish cooperation, with the aim of working on the design of a new icebreaker fleet consisting of three Swedish and two Finnish icebreakers.