Emissions keep on slowly shrinking

Air pollutant emissions from land-based sources are continuing to fall slightly, but considerably slower than before. Some of the reductions on land are also countered by rising emissions from international shipping.

Since 1980, total European emissions of sulphur dioxide (SO₂) – the most significant acidifying pollutant and an important precursor to health-damaging secondary fine particles (PM2.5) – from land-based emission sources have fallen by 86 per cent, from around 53 million tonnes in 1980 to 7.2 million tonnes in 2013.

Emissions of nitrogen oxides (NOx), non-methane volatile organic compounds (VOCs), and ammonia have also gone down, although to a lesser extent. VOCs have more than halved (-58 per cent) since 1980, while NOx and ammonia emissions have dropped by 46 and 34 per cent, respectively.
Historic emissions of primary particulate matter (PM2.5) are not as well documented as those of other air pollutants, and many countries lack emissions data for the 1990s. Between 2000 and 2013 it is estimated that emissions of PM2.5from land-based sources have fallen only by 13 per cent, from 3 to 2.6 million tonnes.

Although overall emissions continue to fall, the downward trend has flattened out over the last five-ten years, especially in the case of ammonia and primary particles.
Looking specifically at the 28 member states of the European Union, between 1980 and 2013 the emissions of SO₂ came down by as much as 91 per cent, while those of NOx and VOCs fell respectively by 53 and 60 per cent. Emissions of ammonia – which emanate primarily from agricultural activities – fell by only 27 per cent. Primary PM2.5 particles were reduced by 23 per cent between 2000 and 2013.

Emissions of SO₂ from international shipping in European waters showed a steady increase up to around 2006, after which emissions have fallen, primarily as a result of sulphur regulation. The emission reductions were particularly marked in the northern Sulphur Emission Control Areas (SECA), which cover the Baltic Sea and the North Sea, including the English Channel. Between 1980 and 2013, overall ship SO₂ emissions came down by about 10 per cent.
Ship NOx emissions appear to have stabilised, and even come down somewhat, during the economic crisis (2008–2009), but because of a lack of effective ship NOx regulation, they are likely to start increasing again as the economy and trade grow. Compared to 1980, ship NOx emissions have increased by nearly a quarter.

The data in Table 1 is based on figures reported by countries themselves to the Convention on Long-range Transboundary Air Pollution, and was compiled by the European Monitoring and Evaluation Programme (EMEP). The Convention’s EMEP keeps track of the ways in which emissions from one country affect the environment in others. The EMEP report also provides an overview of calculations for source-receptor relationships (including transboundary movements between countries), covering acidifying, eutrophying, photo-oxidant, and particle pollution.
For most European countries the biggest share of depositions of sulphur and nitrogen emanate from outside their own territory, and an increasing share of the depositions originate from international shipping.

Sice land-based emissions of SO₂, NOx and PM2.5 have been falling much faster than those from international shipping, shipping’s contribution to pollutant depositions and concentrations has been getting bigger and bigger over time. For 2013 it was estimated that ship emissions were responsible for ten per cent or more of the total depositions of both sulphur and oxidised nitrogen compounds in many countries (see Table 2). In the coastal areas of these countries, shipping’s contribution to the overall pollution load is even higher. Countries that are particularly exposed to air pollution from shipping include Portugal, Denmark, Norway, Sweden, Ireland, the Netherlands, Spain, France and the United Kingdom.Christer Ågren

Report: “Transboundary particulate matter, photo-oxidants, acidifying and eutrophying components.” EMEP Report 1/2015

Table: European countries where the proportion of air pollutant depositions of sulphur and oxidised nitrogen from ships is the most marked.