Science and technology methodology and associated work plan

The MEGAPOLI project will be realised by 23 partners, representatives of leading research organizations in atmospheric pollution, meteorological and climate research, and organizations responsible for the urban air quality and population exposure forecast and control from 11 European countries. This breadth guarantees that the project can accomplish its ambitious objectives and tasks, ranging from the collection and analysis of state-of-the-art measurements to the continued development and application of complex numerical models to the distribution of results in a form directly usable by the end users and understandable by the public. The project also requires a very strong management and co-ordination due to its broad scientific basis. This will be accomplished through well-defined workpackages and its “management problem-solving approach”.

Realisation of the objectives of the project as well as answering the key scientific questions (see Sect. 1.2) will be accomplished via nine separate but inter-linked Work Packages (WPs), which are shown schematically in Figure 3. The WPs are described below, first in terms of an overview of the workpackage concept and of the megacities in focus, and then in a more detailed description of the state-of-the-art and our plans to advance beyond this for each WP.

Overall strategy and general description

The first critical step in improving our understanding of how megacities impact air quality, atmospheric composition and climate on different scales is the development of high-quality inventories of the emissions of relevant gases and aerosols and their precursors, and determining how these are anticipated to change in the mid-term future, as well as how these change under various scenarios (e.g, movement of 10% of the population out of a megacity and into the surrounding countryside). This will form the key input to the remaining components of the study,and will also, through an understanding of the sensitivity of emissions of different compounds and from different sectors, form the basis for sensible approaches to mitigation strategies. This task will use as a starting point the corresponding emission inventories developed by local administrations for major urban areas. These will be improved when necessary, adjusted to the appropriate model scale and integrated into larger scale datasets for their use in regional and global scale atmospheric composition modelling. This approach will allow the exploitation of former investments and available information, and will build connections between local air quality management authorities and the air quality and climate research community. Emissions are the focus of WP1 in the project, and its links to the other aspects of the project as shown in Figure 3. WP2 is focusing on the megacity features (e.g. morphology), along with processes taking place in the urban canopy and boundary layer, which are responsible for the airborne transport and transformation of pollutants and urban climate effects. This WP is aimed at the development of databases of morphology/land-use classifications for megacities, as well as developing databases and sub-grid parameterisations of urban layer processes for megacity, regional and global scale models.

Figure 2: Schematic showing the main linkages between megacities, air quality and climate. The connections and processes will be the focus of MEGAPOLI. In addition to the overall connections between megacities, air quality and climate, the figure shows the main feedbacks, ecosystem, health and weather impact pathways, and mitigation routes which will be investigated in MEGAPOLI. The relevant temporal and spatial scales are additionally included.

Pollutant emissions impact the chemical composition of the atmosphere on different scales. This in turn influences the climate through radiative transfer and effects on clouds and the hydrological cycle. These issues will form the core of the project, and will be analysed by four workpackages (WP3-6) (Figure 3).

WP3 will focus on the characterization of aerosols and relevant precursors at urban and surrounding non-urban areas. Field measurements will be conducted to examine the evolution of aerosols and gas-aerosol interactions in the urban outflow of the Paris megacity. Paris has been chosen for various scientific and logistical reasons, but mainly because it is a very concentrated European urban pollution hot spot surrounded by rural areas. The objective of WP4 is to improve our understanding and modelling of local and urban-scale impacts of megacity emissions, on the urban and the surrounding area air quality (WP4). Continental and global scale impacts of megacities on atmospheric composition and climate will be considered in WP5 and WP6. These WPs will also consider the effects of future climate and emission scenarios. Each WP activity will comprise basic research concerning the individual processes critical for understanding the impacts analysed. Additionally, applied research will be devoted to building bridges between the scales and aspects previously introduced, and towards developing integrated assessment tools to define impacts and mitigation strategies.

The information from WPs 1-6 will be brought together in WP7 and WP8. In WP7 the information and model developments from WPs 1-6 will be used to develop integrated tools for prediction of megacity impacts on air quality. In this WP, the integrated methodology will be implemented to assess the air quality and climate impacts of selected world megacities by employing improved models from WPs 4, 5 and 6. In addition, the results of the atmospheric and climate modelling will be used to estimate and assess (in monetary terms) impacts on human health and ecosystems and climate change impacts of megacities with a methodology developed in WP8. Finally, the information from the integrated assessments will be input into WP8, focusing on mitigation options, which will be assessed by creating scenarios of possible future developments of megacities, in which these options are implemented. The emissions for these scenarios are calculated in WP1 and used as input for the integrated modelling. By comparing the results, the different scenarios and policy options are assessed.

Figure 3: Work Packages (WPs) structure and integration.

The results of the project will be disseminated to the Commission, policy makers and the public by WP9, which will also oversee the coordination of the individual work-packages. Results and instruments made available by WP deliverables will support the definition of areas and scales of effective measures to improve present and future air quality in large conurbations.

FP7 EC MEGAPOLI, 2008-2011