Ships in Danish waters emit as much sulphur dioxide as Denmark, Norway and Sweden combined

A survey from the Danish Environmental Protection Agency (EPA) shows that sulphur dioxide (SO2) emissions from ships in the waters around Denmark were far higher than expected, exceeding all sources including heating, road transport and energy generation in Denmark and its two Scandinavian neighbours.

The report shows that shipping in the waters around Denmark emitted 133,000 tonnes of sulphur dioxide in 1999/2000, twice as much as all the land-based sources in Denmark combined. The survey covers emissions from ships of all types and nationalities that have sailed through the waters around Denmark, with cargo ships the main problem, being responsible for over 95% of SO2, 76% of carbon dioxide and 86% of nitrogen oxide emissions (NOx).

For other ocean-going vessels, however, the general picture is somewhat better, with energy consumption by ferries falling by 33% from 1996 to 2000, and sulphur emissions from leisure craft also falling significantly over the same period.

The Danish EPA points out that shipping is the most energy-efficient method of transport with no other way of transporting goods contributing less greenhouse gases, but says that the sector does impact the environment more than was expected. However, a report last year said that the world’s biggest ships account for 14% of total NOx and 16% of all SO2 emissions from petroleum sources around the world (see related story). Emissions of sulphur dioxide and nitrogen oxides lead to acidification of land and aquatic areas throughout Scandinavia, but the Danish EPA says that the problem is greater in Norway and Sweden than it is in Denmark.

“In Denmark, acidification from land-based sources is well under control, not least because of initiatives such as requirements for desulphurisation of flue gases in power plants, low sulphur content in oils, use of power/heat, and the conversion from coal and oil to natural gas,” said Deputy Director General at the Danish EPA, Karsten Skov. “It now appears, however, that we must also limit emissions of sulphur dioxide from international shipping if acidification in Scandinavia is to be reduced effectively.”

The EPA says that a reduction in the sulphur content of fuels would be an effective and cheap way of reducing acidification while the Danish Maritime Authority has started detailed assessment of new initiatives in close cooperation with the EPA. One possibility considered could be to introduce discounts on shipping and harbour duties for ships with reduced emissions – a method which Sweden has put into use. Firstly, however, the Danish EPA will concentrate on international regulation.

“The Danish EPA will work to see that a supplement to the MARPOL Convention, which has already been adopted by the International Maritime Organisation, enters into force as soon as possible,” Skov said. “This will reduce the maximum permitted sulphur content in ship fuel in the North Sea and the Baltic Sea to 1.5%. Sulphur content today is about 3% on average. Denmark will probably endorse the supplement during this year, but as a large number of countries, which together are responsible for over 50% of world shipping, also have to endorse the supplement, it may take some time before it enters into force.”

Denmark has also announced that it is to be the first European Union nation to ratify the Kyoto Protocol.

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