The manual describes methods for calculating critical loads and levels as well as for dynamic modelling to be used by National Focal Centres (NFCs) of the LRTAP Convention. It provides harmonized indicators to assess the impacts of, e.g. acidification, eutrophication, heavy metals, ozone and particulate matter, on terrestrial and aquatic ecosystems, crops or building materials, respectively. This manual provides the scientific basis for the application of critical loads and levels. The choice of indicators and receptors for the risk assessments is coordinated with the needs of policy development.
The most recent version of the Mapping Manual
The chapters of the Manual have been updated individually and can be downloaded from the links below:
Chapter 1 - Introduction (2015)
Chapter 2 - Guidance on Mapping Concentration Levels and Deposition Loads (2014)
Chapter 3 - Mapping Critical Levels for Vegetation (2017)
Chapter 4 - Mapping of Effects on Materials (2021)
Chapter 5 - Mapping Critical Loads for Ecosystems (2017)
Chapter 6 - Dynamic Modelling (2015)
Chapter 7 - Exceedance Calculation (2015)
Chapter 8 - General Mapping Issue (2015)
CLRTAP (2004) Manual on Methodologies and Criteria for Modelling and Mapping Critical Loads and Levels and Air Pollution Effects, Risks and Trends. Umwelbundesamt, Berlin.
The 2004 version of this Manual (available in English and Russian) was mostly discussed and adopted by the 19th meeting of the ICP M&M Task Force in Tartu, Estonia (May 2003); some additional parts were discussed and adopted by the 20th meeting in Laxenburg, Austria (May 2004). This version replaces the previous (1996) Manual.
Background documents
Nilsson J, Grennfelt P (eds.) (1988) Critical Loads for Sulphur and Nitrogen. Reprint of the workshop report, Skokloster, Sweden.
Sverdrup H, Warfvinge P (eds.) (1993) The effect of soil acidification on the growth of trees, grass and herbs as expressed by the (Ca+MG+K)/AL ratio. Reports in ecology and environmental engineering. Lund University, Department of Chemical Engineering II, 2nd revised edition, Lund, Sweden.