Energy Indicators for Sustainable Development: Guidelines and Methodologies International Atomic Energy Agency United Nations Department of Economic and Social Affairs International Energy Agency Eurostat European Environment Agency

ASSESSMENT OF DATA 
(a) Data Needed to Compile the Indicator: Critical load values for total acidity of 
sulphur and nitrogen, combined with acid deposition values, in order that exceedance 
values can be produced showing the area of soil where critical loads are being 
exceeded. Countries should make clear the data validation processes for the 
emissions, deposition and critical load determinations that are used as the basis for the 
development of the indicator. 
(b) National and International Data Availability: Critical loads are calculated by 
the countries of the CLRTAP and are collected and mapped over Europe by the 
Coordination Center for Effects (CCE). Every year, emissions data are reported by 

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national authorities under the CLRTAP. The emissions data include both new 
estimates of emissions for two years in areas and updated information on emissions 
from previous years. The emissions data are stored and verified in the European 
Monitoring and Evaluation Programme’s Meteorological Synthesizing Centre — 
West (EMEP/MSC-W). On the basis of these emissions, EMEP/MSC-W carries out 
calculations of atmospheric transport of sulphur and nitrogen pollutants according to 
recorded meteorological conditions. Updated deposition calculations are used as a 
basis for the calculation of exceedances of critical loads at the CCE. Results are 
presented in the yearly update of the EMEP report on Transboundary Acidification 
and Eutrophication in Europe. 
REFERENCES 
• Bouwman, L., van Vuuren, D., 1999. Global Assessment of Acidification and 
Eutrophication of Natural Ecosystems. Bilthoven, the Netherlands: United 
Nations Environment Programme (UNEP)/ National Institute of Public Health 
and the Environment (RIVM) (www.rivm.nl/env/int/geo). 
• De Vries, W., Posch, M., Reinds, G.J., Kämäri, J., 1993. Critical Loads and 
Their Exceedance on Forest Soils in Europe. Report 58 (revised version). 
Wageningen, The Netherlands: DLO The Winand Staring Centre for 
Integrated Land, Soil and Water Research. 
• Downing, R., Hettelingh, J.-P., de Smet, P., eds, 1993. Calculation and 
Mapping of Critical Loads in Europe. Status report 1993. CCE/RIVM Rep. 
259101003. Bilthoven, the Netherlands: Coordination Center for Effects 
(CCE), National Institute of Public Health and the Environment (RIVM). 
• EEA, 2003. Air Pollution in Europe 1990–2000. Topic report no. 4/2003. 
Copenhagen, Denmark: European Environment Agency. 
• Nilsson, J., Grennfelt, P., eds, 1988. Critical Loads for Sulphur and Nitrogen. 
NORD 1988:97. Copenhagen, Denmark: Nordic Council of Ministers. 
• Posch, M., Hettelingh, J.-P., de Smet, P.A.M., Downing, R.J., eds, 1999. 
Calculation and Mapping of Critical Thresholds in Europe. Status Report 
1999, Bilthoven, the Netherlands: Coordination Center for Effects (CCE), 
National Institute of Public Health and the Environment (RIVM). 
• TCDC/ECDC Network, Acidification in Developing Countries: Ecosystem 
Sensitivity and the Critical Load Approach on a Global Scale. Beijing, China: 
Technological Cooperation among Developing Countries (TCDC)/Economic 
Cooperation among Developing Countries (ECDC) Network. Available at 
http://www.ecdc.net.cn/events/report/acid/acidification.htm. 
• UNEP/ISSS/FAO/ISRIC, 1995. Global and National Soil and Terrain Digital 
Databases: Procedures Manual (revised edition). Wageningen, the 
Netherlands: International Soil Reference and Information Centre. 

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