WP8: Mitigation, policy options and impact assessment

Overview and background

This work package will deal with the beginning and the end of the full chain or impact pathway approach of integrated assessments to be carried out in the project. In a project like MEGAPOLI, it is important to define policy questions to be answered in the assessment, and to create scenarios, at the beginning of the project, while towards the end it becomes important to assess the impacts of different policy options and prepare recommendations for specific actions in cooperation with policy makers, in particular the megacity administrations and the EC. Examples for policy questions which need to be addressed include:
Short term (2010/2020): Can the PM10 and PM2.5 thresholds be met with current and currently planned measures? What are the health and climate change impacts? Which additional policy strategies and which additional abatement measures are available to reduce health risks, ecosystem damage and climate change impacts; what are costs and benefits of these measures, beyond the impacts of the ‘base line’ development? Is it possible at all to meet the current PM10 and NO2 thresholds with additional feasible measures? What is the effect of climate change and climate change strategies on air pollution and vice versa? How can the challenges from upcoming environmental regulations be met (thematic strategy on air quality, post-Kyoto aims, new NEC directive)?
Long term (2030-2050): What are the options and effects of long term city planning and urban management in the long run (including changes in the number of inhabitants and working places)? How beneficial are these changes (e.g. better air quality, but higher energy demand, if population density decreases)? What is the potential of such changes?

Methodology and advancement beyond the state-of-the-art

The policy questions outlined above will be addressed by generating scenarios – descriptions of possible consistent future developments of the megacities and the surrounding regions (i.e. Europe for the European cities) – and comparing the impacts of the different scenarios. The scenarios will be used to generate an emission data set for each scenario (in WP 1), which will then be used as input for the integrated assessment tool to be run in WP 7. Output of these model runs will be maps and parameters describing air quality, deposition and impacts on climate change for each scenario. These results will be assessed in the following ways: first the compliance with current existing thresholds will be examined, and using cost-benefit analyses, bundles of measures that fulfil certain aims with least costs can be identified. Secondly, to be able to analyse the importance of air quality and climate changes, the results will be converted into damages using the impact pathway approach developed in the ExternE project series including the currently running FP6 projects NEEDS and EXIOPOL, and based on the findings of the FP6 projects INTARESE, HEATCO, HEIMTSA, CAIR4HEALTH and ENVIRISK. Health risks will be calculated using concentration-response- and exposure-response relationships developed and recommended in these projects, different health endpoints can then be aggregated using DALY’s (disability adjusted life years). Climate change damage is assessed using results from the FUND model (developed by R. Tol, University of Hamburg) and by analysing studies on climate change impacts including the IPCC report and DEFRA studies. Damage to ecosystems from acidification and eutrophication is assessed with a method developed in the NEEDS project using ‘potentially disappearing fractions’ of species as damage indicators.

To be able to compare the different damage categories with each other and with costs of measures, the damage indicators should be converted into a common unit; here monetary units are chosen using contingent valuation, which measures the preference of the population, e.g. by surveys about the willingness to pay to avoid a (small) risk, as means to allocate monetary values to risks and damages. Again, results of the above mentioned projects, especially NEEDS, are used. Using the monetized results, cost-benefit analyses can be carried out (for short and medium term measures, for long term measures benefits are calculated). To be able to generate these results efficiently, a computer tool is developed (task 3 of this WP).

A first analysis will ask about the development of impacts from megacities, for the case that no additional measures are implemented. For that, a baseline scenario will be developed together with WP1, assuming a trend development of activities and emission factors that takes into account current legislation and legislation in the pipeline. Available policy options (possibilities for implementing instruments by the policy makers to accomplish their goals), which could be implemented in addition to those of the baseline scenario, will be systematically collected. Assumptions will have to be made about how the operators and users of emission sources react to these options, i.e., which abatement and mitigation measures they will implement. Both technical measures (changing emissions factors, e.g., an additional filter) and non-technical measures (which change the decisions and the behaviour of users of emission sources, e.g., by implementing a charge on emissions) will be addressed. The whole analysis will be carried out for the 1st level cities and agglomerations: Paris, London, Rhine-Ruhr and the Po Valley. In addition, Mexico-City will also be analysed as an example for cities in developing countries with quite different development prospects and features. The definition and the assessment of the scenarios are carried out in close cooperation and discussion with the main stakeholders, especially the administration of the megacities that are analysed, and the EC; this is achieved and planned in task 2 of the WP.

A major innovation of this project is that it strives for a full integrated assessment of megacities. Policy options and mitigation measures generally influence the emission of more than one pollutant, thus for assessing such measures all effected impacts have to be taken into account. In addition, especially the relationship between climate change and air pollution is important, but not yet fully analysed. Thus the integration occurs:
- across impacts, especially climate change impacts and air pollution impacts, including health risks and ecosystem damage;
- across pollutants and emission sources, e.g. transport, energy conversion, industry, households, waste, agriculture, natural and biogenic processes; PM10, PM2.5, ozone, acid substances, nutrients, greenhouse gases, and others;
- across scales: local, urban, regional, global; short, medium and long term.

The assessment of policy and mitigation options will be based on the simultaneous assessment of all relevant changes in damages and risks caused by the option (and not on the potential, e.g., with regard to the reduction of a single pollutant). The estimation of health, ecosystem and climate change impacts will be based on the current state of knowledge as currently analysed in running EC projects. For the first time, Eulerian atmospheric models and climate change models will be directly coupled (via the internet) with impact assessment models. The transformation of results into monetary units will allow us to carry out cost-benefit analyses. A final innovation lies in the interdisciplinary cooperation of city planners (UHam) with atmospheric and climate change scientists.

FP7 EC MEGAPOLI, 2008-2011