2.1 Anthropogenic driving forces for air pollution emissions
Anthropogenic activities such as energy consumption, industrial activities and agriculture are major driving forces of emissions of air pollutants. Their future development has a strong influence on the level of future emissions and on the potential and costs for maintaining emissions at environmentally acceptable levels. Unfortunately, it is an ambitious task to accurately model the future development of anthropogenic economic activities at the level of detail that is required for the assessment of air pollution. A number of economic theories compete in this field, and their modelling entails complex approaches and a variety of detailed assumptions, which are difficult to quantify on an undisputed basis. Thus, as a first choice, it has been decided not to embark with the RAINS model on the modelling of future economic activities, but to derive projections from other sources as an exogenous input to the RAINS model.
However, numerous scenario studies with the RAINS model have shown that modifications in these exogenous drivers (e.g., energy consumption, agricultural activities) yield in many cases larger and more cost-effective potentials for reducing emissions than the application of add-on/end-of-pipe emission control technologies (Syri et al., 2001; Barkman et al., 2003; Rentz et al., 1994). For these studies, interfaces between the RAINS model and specialized energy models (PRIMES, TIMER, EFOM, MESSAGE) have been developed that allow the import of alternative energy scenarios into the RAINS database.
The strong impact of alternative economic projections on air pollution raises two important issues for the RAINS calculations: First, policy interventions that influence such driving forces could turn out to be a very cost-effective means for controlling air pollution, and an integrated assessment needs to take this potential into account. Second, when developing baseline projections of future air quality and searching for cost-effective emission control strategies, uncertainties in these projections cannot be ignored and strategies need to be found that are robust against these uncertainties in the input drivers.
To address the first concern, a rule-based software interface between the PRIMES energy model and the RAINS model has been developed, which requires only minimal additional expert knowledge.
This interface opens the possibility for the analysis of a larger number of energy scenario variants.
Similar action is underway to convert alternative projections of agricultural activities developed with the CAPRI model of the University of Bonn into the RAINS databases. Comparative air quality analyses for alternative economic projections will identify factors and structural measures in the economy that have beneficial impacts on air pollution control strategies.
It remains difficult to interpret any of the projections as an accurate prediction of future development.
Thus, any calculation of an emission (control) scenario based on a particular energy or agricultural projection is loaded with significant uncertainties. In many cases, the uncertainties resulting from the underlying exogenous assumptions (e.g., on energy prices, economic development, carbon prices, etc.) dominate uncertainties associated with other parts in the chain of RAINS model calculation (Suutari et al., 2001).
2.2 Projections of emission generating activities
Since it is hard to predict some of the important determinants of future emissions on a reliable basis, the RAINS analysis will focus on the robustness of model results in view of these unavoidable uncertainties. For this purpose, the RAINS databases for the CAFE policy analysis include multiple baseline projections on energy use and agricultural activities:
• A Europe-wide consistent view of energy development with certain assumptions on climate policies (as produced by the PRIMES energy model).
• As a variant, a Europe-wide consistent view of energy development without climate policies.
For this purpose, RAINS uses the Energy 2030 outlook of DG-TREN.
• A compilation of official national projections of energy development with climate policies that reflect the perspectives of the individual governments of Member States. By their nature, there will be no guarantee of international consistency in the main assumptions across countries (e.g., economic development, energy prices, use of flexible mechanisms for the Kyoto Protocol, assumptions on post-Kyoto regimes, etc.).
For agriculture, RAINS will use
• a set of Europe-wide consistent projections of agricultural activities without CAP reform, and
• a compilation of national projections of activities supplied by Member States.
• In addition, it is foreseen that a ‘CAP reform’ projection will be made available by DG-AGRI once the policy plans are agreed upon.
The policy analysis will then focus on environmental targets that lead to further improvements of air quality and will explore the implications of alternative baseline projections on achieving these targets.
Thus, there is no need to reach full consensus of all stakeholders on all assumptions of each baseline projection, as long as overall plausibility and consistency is maintained.
To the extent available, alternative projections of drivers have been implemented in the on-line version of the RAINS model (http://www.iiasa.ac.at/web-apps/tap/RainsWeb/RainsLogin.htm) and are ready for analysis.
These baseline projections include assumptions about the general economic development, such as GDP growth rates for the different economic sectors,
energy (specifying demand and supply of different fuel types in the various economic sectors), agricultural production (e.g., number of animals),
transport (e.g., fuel consumption by vehicle types, off-road activities, etc.) and
• industrial production (distinguishing different kinds of goods and their production methods).
The baseline projections will be based on full compliance with existing and adopted national and Community legislation (e.g., the Air Quality, LCP and NEC directives). Thus, the projections must comply with the targets that the EU Member States have ratified in the Kyoto Protocol. However, in order to understand the significance of the Kyoto Protocol, a scenario will be prepared where the Kyoto constraint is not binding. This is because it is not known at the moment to what extent the Member States will take advantage of the flexible mechanisms (International Emissions Trading, Joint
Implementation and Clean Development Mechanisms) of the Kyoto Protocol and what the consequent effects on the fuel mix (and thus air pollution) are likely to be. Some other alternative scenarios are also conceivable for the CAFE baseline analysis.
As it is possible that the Member States and Accession Candidate Countries have slightly different views on the driving forces of emissions, it is important to include such views when the CAFE baseline is developed. However, it needs to be emphasised that such alternative views need to be consistent with the national, community-wide and international obligations that the Member State has undertaken. In other words, the possible alternative baseline that is suggested by a Member State or Accession Candidate Country needs to be compliant with, e.g., NEC, LCP and Air Quality directives, as well as the Kyoto Protocol.
2.3 References
Barkman, A., de Leeuw, F., van Vuuren, D., Cofala, J. and Eerens, H. (2003). Air Pollution. In: (ed.) Europe's environment: the third assessment. Environmental Assessment Report No 10,.
European Environment Agency, Copenhagen
Rentz, O., Haasis, H.-D., Jattke, A., Russ, P., Wietschel, M. and Amann, M. (1994) Influence of energy supply structure on emission reduction costs. Energy 19(6): 641-651.
Suutari, R., Amann, M., Cofala, J., Klimont, Z., Posch, M. and Schöpp, W. (2001) From Economic Activities to Ecosystem Protection in Europe. An Uncertainty Analysis of Two Scenarios of the RAINS Integrated Assessment Model. EMEP CIAM/CCE Report 1/2001, International Institute for Applied Systems Analysis, Laxenburg, Austria.
Syri, S., Amann, M., Capros, P., Mantzos, L., Cofala, J. and Klimont, Z. (2001) Low CO2 energy pathways and regional air pollution in Europe. Energy Policy 29: 871-884.