Genesis of the Convention and its Protocols

Initially conceived as a flexible framework for cooperation, the Convention soon provided a forum for Parties to negotiate and agree on binding obligations to reduce emissions. To date, the Convention has been extended by eight protocols containing legally binding targets for emission reductions. 

Over the 35 years since its signing, the Convention has gone through a number of phases. In the beginning, the focus was on building a sound scientific base. Subsequently, emphasis was put on development and negotiation of gradually more advanced protocols, while at the same time ensuring that the scientific knowledge was kept up to date. Examination and review of protocols as well as implementation and compliance are marking the current phase. 

The first protocol that was signed under the Convention (The 1984 Geneva Protocol on Long-term Financing of the Cooperative Programme for Monitoring and Evaluation of the Long-range Transmission of Air Pollutants in Europe (EMEP) (hyperlink) did not set any emission reduction targets, but provided a financing scheme to fund the activities under the Co-operative Programme for Monitoring and Evaluation of the Long-range Transmission of Air Pollutants in Europe (EMEP). As the scientific backbone of the Convention, EMEP has since provided information to Governments on the emission, transport and deposition of air pollution.

With acid rain and acidification of rivers and lakes being the starting point for the negotiations of the Convention, sulphur dioxide (SO2) was already mentioned in the Convention text. This led to the negotiations of the first substantive protocol on air pollution abatement under the Convention, the 1985 Helsinki Protocol on the Reduction of Sulphur Emissions or their Transboundary Fluxes by at least 30 per cent (hyperlink).

Soon it became clear that to reduce acidification, other pollutants also had to be tackled. It was recognized that nitrogen compounds contributed to acidification. In addition, nitrogen deposition and its eutrophying effects, which had caused ecosystem changes, prompted Parties to the Convention to negotiate the 1988 Sofia Protocol concerning the Control of Emissions of Nitrogen Oxides or their Transboundary Fluxes (hyperlink).

In subsequent years, Parties to the Convention recognized that volatile organic compounds (VOCs), in addition to nitrogen oxides, which were already regulated under the 1988 Protocol, were contributing to the formation of ground-level ozone and other photochemical oxidant products, causing damage to vegetation and crops. To reduce VOCs, Parties adopted the 1991 Geneva Protocol concerning the Control of Emissions of Volatile Organic Compounds or their Transboundary Fluxes (hyperlink).

While the first three substantive protocols to the Convention (1985 Sulphur Protocol, 1988 Protocol on Nitrogen Oxides and the 1991 Protocol on VOCs) addressed one substance at a time and prescribed the same flat-rate emission reductions for all Parties, the 1994 Oslo Protocol on Further Reduction of Sulphur Emissions (hyperlink) took a new approach. It was the first protocol to derive its quantitative reduction obligations from the cost-effectiveness and effect-based principles. Its reduction obligations were based on the results of modelled linkages between the SO2 emissions of each country and the exposure of different ecosystems, taking into account the sensitivity of such ecosystems to acidification. For the first time, Parties thus negotiated on the basis of the critical loads approach, which made it possible to achieve agreed benefits at minimal overall cost by setting country-specific ceilings for sulphur emissions. It thus led to a differentiation of emission reduction obligations of Parties to the Protocol, opening the door to true polluter pays burden sharing, which can be seen as a milestone in Europe.

Subsequent negotiations under the Convention then focused on two other sets of pollutants: heavy metals and persistent organic pollutants (POPs). The two Protocols that resulted from these negotiations, the 1998 Aarhus Protocol on Persistent Organic Pollutants (POPs) (hyperlink) and the 1998 Aarhus Protocol on Heavy Metals (hyperlink) addressed, for the first time, a group of pollutants, which would further pave the way for a more complex approach to designing protocols. 

In many ways the 1999 Gothenburg Protocol to Abate Acidification, Eutrophication and Ground-level Ozone (Gothenburg Protocol) (hyperlink) can be regarded as a turning point in the history of the Convention. The decision to review the Protocol on Nitrogen Oxides gradually grew into a combined review of the 1991 Protocol on VOCs and the1994 Sulphur Protocol, which culminated in the first multi-pollutant and multi-effect protocol. Building on the cost-effectiveness and effect-based principles, the Gothenburg Protocol comprises specific national emission ceilings for sulphur dioxide, nitrogen oxides, ammonia and volatile organic compounds. 

The revised Gothenburg Protocol, which is not yet in force, is also the first binding agreement to include emission reduction commitments for fine particulate matter. Also for the first time, the Parties have broken new ground in international air pollution policy by specifically including the short-lived climate pollutant black carbon (or soot) as a component of particular matter. Reducing particulate matter (including black carbon) through the implementation of the Protocol is thus a major step in reducing air pollution, while at the same time facilitating climate co-benefits.

Emission data tables 

Twice a year the secretariat, in cooperation with the Centre on Emission Inventories and Projections (CEIP), compiles overview tables of the emission data by pollutant in relation to the respective emission reduction obligations set for each Party under the different protocols: