

Burning of agricultural waste is still practised in parts of Europe. Photo: © Bilanol / Shutterstock.com
Farm emissions high on Air Convention agenda
The last CLRTAP meeting featured a new guidance on agricultural waste burning, a new assessment report on ammonia, and the inclusion of methane in the revision analysis.
The United Nations Economic Commission for Europe (UNECE) held the 41st session of the Executive Body for the Convention on Long-range Transboundary Air Pollution (CLRTAP), also known as the Air Convention, on 6–8 December 2021. The Air Convention came into force almost 40 years ago and counts more than 50 countries as parties, including the EU, Canada, the United States, and several other European and Central Asian countries. The Air Convention has been extended to include eight specific protocols. The Gothenburg Protocol to Abate Acidification, Eutrophication and Ground-level Ozone covers five of the main air pollutants: sulphur dioxide, nitrogen oxides, ammonia, volatile organic compounds (VOCs) and particulate matter (PM2.5). Black Carbon (BC) is only regulated under the Gothenburg Protocol as a component of particulate matter. New guidance was adopted at the 41st session suggesting that within the UNECE region, additional measures for wood-fuelled heating stoves and agricultural waste burning can reap the biggest benefits in reducing both PM2.5 and BC emissions, promising benefits for air quality, climate, biodiversity and health. While guidance for wood burning had already been adopted in 2019, the focus this time was on guidance to reduce emissions from agricultural waste burning. There was agreement that agricultural waste burning has many negative impacts, such as air pollution, greenhouse gas emissions, soil erosion, loss of biodiversity and soil nutrients, of which the latter must be replaced by using expensive fertilisers to maintain crop yields.
Agricultural practices were also discussed in the context of a new assessment report on ammonia (NH3), finding the need for a 30–50% reduction within the UNECE region to avoid damage to ecosystems and health. Ammonia from agriculture is the culprit for many environmental problems, as a PM2.5 precursor and by polluting water and damaging ecosystems, and is regulated under the Gothenburg Protocol. While the damage that ammonia emissions cause to public health and ecosystems costs €10–25 per kg of ammonia, the abatement costs vary from €0 to €4 per kg of ammonia for most countries, and up to €15 per kg of ammonia in some areas with a high density of livestock. Parties at the 41st session of the Executive Body also welcomed the imminent entry into force of the Protocol on Persistent Organic Pollutants (20 January 2022) and the Protocol on Heavy Metals (8 February 2022), promising further benefits for clean air in the region.
Another important emission in agriculture is methane, and reductions would be of great benefit to both air quality and climate. Methane emissions are not yet directly regulated in the Gothenburg Protocol. The Parties agreed to include methane in the analysis for the revision of the Protocol, which is a promising first step for future inclusion of methane in the protocol in the future.
The ongoing Gothenburg Protocol review was also discussed with some insight on how the Convention could evolve in the years to come through stronger cooperation both within and beyond the UNECE region. To strengthen this, the Convention Parties launched a new initiative in 2019, the forum for international cooperation on air pollution, to exchange information and mutual learning at both technical and policy levels and enable greater international cooperation on solutions to improve air quality globally. The Parties established a new Task Force for International Cooperation on Air Pollution, chaired by Sweden and the UK and consisting of experts from Parties and other interested countries and international organisations.
Ebba Malmqvist