Emissions of acidifying substances
Assessment made on 01 Jan 2001
ClassificationAir pollution (Primary theme)
Policy issue: Are we reaching emission targets for acidifying substances?
Emissions in acidifying gases fell by 32% between 1990 and 1998, due mainly to changes in power station fuel and technology.
The effects of sulphur dioxide, nitrogen dioxide and ammonia emissions - acid rain, eutrophication and damaged forests, rivers, seas and land - were one of the first major environmental problems on a European scale taken seriously by society at large.
New regulations obliged power station operators to install desulphurisation systems in their plants, while economic factors saw many switch from coal and heavy oil towards natural gas, which by its very nature produces less acidifying gases (see Energy). The 1990s also saw major economic restructuring in the new German Lander. As a result, emissions in sulphur dioxide fell by 70%.
'Cleaner exhaust' systems were also introduced into motor vehicles, reducing the average emission of nitrogen oxides per vehicle. This, however, was offset by increasing road traffic, so the EU missed its 5th Environmental Action Programme target of reducing nitrogen oxides emissions to 30% below those in 1990 by 2000.
Ammonia emissions, finally, are stabilizing, although the data on the contribution of the agricultural sector - the largest source of ammonia emissions (see Agriculture: Nutrient surplus) - are uncertain, with emissions from this sector difficult to control.
When the acidifiying potential of each substance is calculated, the overall sum shows a 32% drop over the 1990-1998 period. While this progress is welcome, however, further reductions are required to reach the target set.