34th Annual Report 2025: Convention on Long-range Transboundary Air Pollution : International Cooperative Programme on Integrated Monitoring of Air Pollution Effects on Ecosystems

The Integrated Monitoring Programme (ICP IM) is part of the effect-oriented activities under the 1979 Convention on Long-range Transboundary Air Pollution, which covers the region of the United Nations Economic Commission for Europe (UNECE). The main aim of the ICP IM is to provide a framework to observe and understand the complex changes occurring in natural/semi natural ecosystems. This report summarizes the work carried out by the ICP IM Programme Centre and several collaborating institutes, including:• A short summary of previous data assessments• A status report of the ICP IM activities, content of the IM database, and geographical coverage of the monitoring network• A report on long-term trends in precipitation, throughfall and runoff water chemistry at IM sites• Analysis of changes in above ground carbon pools at the heavily disturbed IM site Aneboda (Sweden)• National Reports on ICP IM activities