Climate change creates new prerequisites for shipping


Year-round shipping is vital for Finland's foreign trade and economy. With milder winters, the sea remains free of ice for longer and longer periods of time. This, together with increasing windiness, may make seas rougher in the winter and make ship transport more difficult. Climate change is also expected to lengthen the boating season.

Importance of efficient shipping for society

Finland's foreign trade and economic development depend on year-round shipping. Ship transport accounts for 90 percent of exports and 70 percent of imports. The volume of shipping is increasing steadily. Approximately 100 million tonnes of goods passed through Finnish ports in 2006, and shipping volumes are estimated to increase to 150 million tonnes by 2030. The considerable increase in the number of oil shipments in the Gulf of Finland contributes to the overall increase. [1]

The Finnish coastline is dotted with ports, but the majority of them are small and several different ports are involved in cargo shipping. A total of 23 ports remain operational throughout the year. Icebreakers are needed to keep ports in the Gulf of Bothnia open for a period of approximately six months each year, while three months is enough in the Gulf of Finland. [1]

Sensitivity of sea and inland waterway transport to weather and climatic factors

The weather conditions most pertinent to ship transport include temperatures and the resulting prevalence of ice as well as windiness and storms, which affect swell and set limitations to the types of vessels that can be used. Rainfall also has implications especially on inland waterway transport, as the volume of rain affects flow rates and water levels and therefore the maintenance of shipping channels. [1] [2]

The rise of sea levels caused by climate change will also have implications on shipping in the future. Post-glacial rebound along the Finnish coasts has so far counteracted the effects of rising sea levels, and this will continue to be the case along the coast of the Gulf of Bothnia over the next few decades. Land rises more slowly in the Gulf of Finland, and rising sea levels may override the effect of post-glacial rebound in the future. [2]

Figure 1. Mäntyluoto Harbour in Pori.

© Jouko Lange

Winter sea conditions are changing

The increasingly mild winters brought about by climate change are expected to decrease ice cover and to shorten the sea ice season during the current century. These changes in the levels of sea ice may have significant implications on shipping. On one hand, the shorter sea ice season is likely to benefit port authorities and to lower the operating costs of ports. The shorter sea ice season may nevertheless complicate shipping and make seafaring more dangerous in the Baltic Sea as the sea becomes increasingly vulnerable to winds. Strong westerly and southwesterly winds may cause pack ice to form and create thick belts of brash ice around winter ports in the Gulf of Finland and the eastern parts of the Gulf of Bothnia, hindering and slowing down shipping. The potential increase of violent winds is one of the challenges facing winter shipping in the future, although forecasts about changes in windiness are still relatively uncertain. [2]

Figure 2. A ship caught in ice. Climate change may make sea ice conditions more treacherous in places.

© Riku Lumiaro

Changes in sea ice conditions also affect the international rankings of Finnish ports. Northern ports that compete with the ports located in the Bay of Bothnia, such as Murmansk in Russia, may benefit from the changes. As climate change progresses, the use of the Northern Sea Route is likely to increase especially in late summer to begin with, cutting shipping times between Europe and Asia considerably. [3]

The boating season may become longer

Increasing average temperatures are likely to lengthen the boating season and to increase the popularity of boating both in inland waterways and at sea. This may lead to an increase in the number of inexperienced boaters, which may pose challenges to shipping. The increasing likelihood of violent winds and thunderstorms resulting from climate change may also put boaters in danger. [2]

Figure 3. A local marina. The longer boating season may increase the popularity of boating.

© Pirjo Ferin-Westerholm

From the perspective of inland water transport, the most important effects of climate change include increasing rainfall and the resulting local floods and higher flow rates. This may limit navigability by lowering bridge clearances, for example. On the other hand, low water levels during dry spells may restrict the passage of larger vessels in some places. [1]

Climate policy also affects shipping

International efforts to lower greenhouse gas emissions also have implications on shipping, and increasingly strict emissions standards may change the requirements set on fleets. For example, the maximum power of the engines onboard vessels used in commercial shipping may have to be limited due to climate policy. This may lead to more vessels requiring assistance in the face of treacherous sea ice conditions during harsh winters in the future. [3]

Preparing shipping for the effects of climate change

The most readily accepted adaptation measures in shipping include modernising fleets to cope with extreme weather events and improving the visibility, durability, and reliability of safety devices. Contingency planning that takes into account the longer brash ice season at sea and changes in windiness and ice cover may help the shipping industry to adapt to the effects of climate change and to cut costs. Changes in rainfall and the likelihood of droughts may require flood bypass systems, for example, to be revised in inland waterways. From the perspective of hydrographic surveying, climate change increases the need to develop new and better software and hardware. Conditions for winter shipping may not improve, at least not in the near future, because windiness is likely to increase the movement of ice and promote pack ice formation. The future of winter shipping hinges on Finland's ability to engage in increasingly close cooperation with other countries and especially Sweden, in order to ensure that the Baltic icebreaker fleet is stationed where it is needed the most at any given time. Making efficient use of long-term weather forecasts and identifying alternative shipping routes to overcome treacherous sea ice conditions is also important. The capability of providing shipping companies with accurate weather information is a key condition for the success of almost all adaptation measures. [2]