Published 2018-01-04

This post is also available in Swedish

Much to be learnt from combating acidification on land

This year it is 50 years since efforts to combat terrestrial acidification gained momentum. This was highlighted in November with an international seminar in Stockholm, where Mistra was one of the organisers.

Work against acidification on land has been a success story. Across Europe, for example, deposition of acidifying substances, such as sulphur, has decreased sharply in recent decades. How was it achieved? What measures were taken and what lessons can we learn today? These were the starting points for an international symposium that gathered experts from Sweden, the other Nordic countries, the rest of Europe and also the US and China.

‘One important reason why mitigation of acidification was such a success was that politicians and researchers at the 1979 UN Convention on Long-Range Transboundary Air Pollution were able to agree on how emission reductions should be distributed,’ says Mistra’s CEO Åke Iverfeldt, one of the speakers at the symposium.

It was the Swedish scientist Svante Odén who, in 1967, drew attention to the then increasing acidification and its consequences in an opinion piece in Sweden’s daily newspaper Dagens Nyheter. The article was the starting point for intensive research efforts, not least in Sweden and Norway.

Sulphur can be transported across great distances — acidification in Sweden, for example, was caused largely by emissions on the Continent and in the British Isles. A scientific challenge was therefore to link acid deposition to emission sources, and the researchers produced models for how this could occur.

‘The models weren’t perfect, but the researchers were careful to describe uncertainties. That helped to convince the biggest critics too,’ says Iverfeldt, who sees transparency as increasingly necessary, given today’s growing fact resistance.

‘There are uncertainties in everything we do, even if we’re communicating facts.’

There are also opportunities for the research community to understand the political landscape better. The fact that, in the 1970s, Britain accepted that the country’s coal power was contributing to acid deposition in Scandinavia was not only a reflection of trust in science Iverfeldt thinks. It gave the then Prime Minister Margaret Thatcher, otherwise not known as much of an environmentalist, a pretext to crack down on the trade union movement, which was close to the coalmining industry.

‘Environmental research operates in a political global context that can take different forms. Scientists can learn to understand political processes, which are not necessarily always about the actual questions of fact.’

Measures against acidification have often been closely associated with reducing other forms of air pollution. Iverfeldt believes that there is still a growing need for concerted policies, with different environmental problems tackled simultaneously. Mistra has, for example, helped to combat acidification through its ASTA research programme (on international and national abatement strategies for transboundary air pollution), which ended in 2007. The programme helped to bring about the development of international efforts to improve air quality and, for example, to the EU’s Thematic Strategy on Air Pollution.

In future, this kind of systemic approach and the need for concerted policies will grow. Examples of such policies are those for mitigating climate change and reducing air pollution.

‘There’s a need for greater knowledge of concerted policies. Mistra’s considering creating a research programme on concerted policy action,’ Iverfeldt says.

The big picture

There has thus been some mitigation of the risks involved in, and some improvement in our management of, acidification on land. This is pleasing, as far as it goes. However, a great deal remains to be done — especially outside Europe.

Henrik Lundström and Clare James