First results


Background and motivation

The recent reports on the review of the Thematic Strategy on Air Pollution show the evolution of PM10 compliance from the 2010 base year to 2025 (assuming current legislation only), the improvement for the optimised A5 (so-called ‘Central Policy Scenario’) by 2025 and the further compliance achieved in 2030 (see the following figure).


 Compliance Assessment via GAINS 2013 [Amann et al., 2013].

As it can be seen, the 2025 CLE case clearly moves away from a general picture of non-compliance (2010) to more geographically discrete remaining areas of non-compliance. Further European wide measures (already mandated in the CLE) bring significant improvements in terms of compliance especially in the EU-15 Member States. But it is also clear that the potential for EU-Wide measures to further improve compliance becomes limited; this is further underlined by comparing the 2025 A5 scenario with the 2030 MTFR scenario.

In this context of “non-compliance islands”, introducing tougher European-wide measures would likely be significantly more costly than directly addressing the non-compliance areas with specifically designed measures (based on bottom-up Integrated Assessment and using regional/local data). This advocates for regional/local ‘bottom up’ approaches (with tools such as RIAT, LEAQ, etc.) to support the development of effective Air Quality Management Plans to achieve compliance.

Although A5 is a high ambition scenario, it does not substantially change the picture in comparison to 2025 CLE. Targeted technical and non-technical measures should play an increased role to achieve compliance. Such measures (low emission zones, special fuels for captive fleets, captive fleet retrofitting etc.) can only be designed appropriately with ‘bottom up’ tools.

These observations motivate the growing interest in Integrated Assessment Models (IAM) and tools to address the local and regional scales.


APPRAISAL contributes to the Air Quality Directive Review

The European Directive 2008/50 and more recently the Commission Implementing Decision 2011/850 do not specify a particular methodology to devise efficient measures to improve air quality. Although the current Air Quality Directive requires MS to report on modelling methodologies like source apportionment (to distinguish local, regional and trans-boundary emission contributions), clear and harmonized techniques to assess current (which zones are mostly exposed) and future (expected levels with/without abatement measures) air quality levels are not available. 

APPRAISAL recommends the following to improve this process:

  • Harmonize criteria and procedures for developing local emission inventories.

  • Appropriately consider the contributions from emission sources outside the Air Quality plan zone.

  • Provide multi-scale IAM tools to support air quality authorities in selecting efficient mitigation strategies.

  • Promote the use of modelling tools.

  • Further incorporate uncertainty estimation in IAM to assess the robustness of the proposed solutions.

  • Improve exposure estimates to better assess the impacts of poor air quality on health.


APPRAISAL contributes to the design of an Integrated Assessment model Framework

In the frame of the project an Integrated Assessment framework has been designed, classifying (in broad terms) two possible decision pathways:

  • Scenario analysis. This is currently the most commonly used approach to design “Plans and Programmes” at the regional/local scales. Expert judgment or Source Apportionment is used to identify potential emission reduction measures, which are tested through a “scenario analysis” modelling methodology. This approach has the advantage of simplicity but does not guarantee that cost-effective measures are selected. An evaluation of costs and impacts can only be performed "ex-post".

  • Optimization. This approach uses optimization to identify cost-effective measures to improve air quality. During this optimization process, abatement costs and impacts are continuously compared until the least cost set of measures is found, to achieve a given air quality target. This approach guarantees the selection of the set of policies that are cost-effective for a given target and domain, and in principle can incorporate costs and impacts in the optimization procedure.

For both of these two schemes, the DPSIR framework concept has been adapted (see the following figure).

The DPSIR scheme adapted to IAM at regional/local scale. The left figure represents the scenario analysis, while the right figure the optmization approach. The red arrow represents the “feedback on cost-effectiveness”, provided by the optimization approach.


APPRAISAL identifies key areas for future research

Most of the APPRAISAL recommendations on key areas for future research and innovation are related to the decision process (or RESPONSES block within the DPSIR cycle), considering i.e.:

  • Development of more detailed information on abatement measures.

  • Inclusion of socio-economic aspects in the analysis.

  • Better account for “Efficiency/non-technical measures”. These measures are now limited to scenario analysis because of the difficulty to estimate their associated costs. Progress is required to include these measures in optimized IAMs.

  • Multi-scale interactions: as already done for Chemical Transport Models, there is the need to develop IAMs nesting capabilities (one-way/two-ways) to include EU/national constraints in regional analysis, while at the same time providing feedbacks from the regional to the EU/national scale.

  • Provide guidance for developing and using IAM approaches and favour harmonization.

  • Better integrate Air Quality and Climate Change policies in the IAM framework. In a “resource limited” world, efficiency (to get win-win solutions from Air Quality and Climate Change actions) is of extreme importance and requires guidelines to better integrate climate change policies (normally established at national or even international levels) into air quality plans developed at regional/local level.

  • Develop dynamically evolving impact assessments. Current approaches aim at solutions to be reached at a given time horizon and are therefore “static”. But the system is non-stationary (see the effect of the current economic crisis) and it becomes important for decision makers to know when to invest in priority with potential to adapt decisions with time.