Shipborne atmospheric nitrogen emissions higher than those caused by terrestrial runoff

print this

A recent study indicates that the amount of nitrogen oxides emitted into the atmosphere from ships sailing in Finnish territorial waters can be quite significant, actually exceeding that caused by the terrestrial runoff from roads in the entire country.
      According to the findings of the study, the total NOx emissions from the shipping on the Baltic Sea amount to some 370,000 tons a year - more than estimated previously.
      "Even this figure may be too low, while the correct amount of NOx emissions is likely to be some 10 to 20 per cent higher", says researcher Tapani Stipa from the Finnish Institute of Marine Research (FIMR).
     
In the summer months, as much as half of the atmospheric nitrogen oxide emissions are caused by shipping in certain sea areas. However, just around five per cent of the entire atmospheric load of nitrogen of the Baltic Sea is shipborne.
      The presence of nitrogen oxides is bound to encourage the eutrophication of the Baltic Sea, while increasing the growth of algae, for example.
      The information of the shipborne atmospheric nitrogen emissions is based on the results of a project coordinated by FIMR, cooperating with the Finnish Meteorological Institute, the University of Turku, Åbo Akademi, as well as the Estonian Ministry of the Environment.
     
"The shipborne nutrient load is found to be particularly hazardous to the Baltic Sea ecosystem in the summer, when the proportion of the shipborne nitrogen oxides of the overall fallout on the high seas is higher than in the winter", notes Marke Hongisto from the Finnish Meteorological Institute.
      "Moreover, shipping on the Baltic Sea is busy even in the summer, while for example the nitrogen oxides emitted from power plants are at their highest in the winter months", Hongisto adds.
      While shipping volumes are constantly growing, the International Maritime Organisation is planning to restrict the amount of emissions from seaborne traffic.


Previously in HS International Edition:
  Gulf of Finland has slightly higher oxygen level than last summer (14.8.2007)
  Warm August weather favours growth of algae both at sea and in lakes (9.8.2007)

Links:
  FIMR Research: ShipNODep - Deposition and effects of shipborne atmospheric nitrogen emissions
  The Finnish Institute of Marine Research (FIMR)
  International Maritime Organization
  Nitrogen oxide (Wikipedia)

Helsingin Sanomat