MEGAPOLI

Numerous large-scale experimental campaigns have led to a better understanding of the processes that lead to photo-oxidative pollution in major European cities. However, for large cities outside Europe and the United States, there are often significant gaps in our understanding and quantification of air pollution. Furthermore, some emission and formation processes of particulate matter, especially carbonaceous particles, are still poorly quantified, which prevents a comprehensive assessment of the impact of different pollution sources on air quality and health.

The FP7 MEGAPOLI project aims to provide a complete, coherent and more quantitative description of the impact of megacities (large agglomerations with a population of more than 10 million) on air quality, the chemical composition of the troposphere and the climate. To this end, an integrated modelling methodology will be implemented for several dozen megacities in Europe (Paris region, London, Moscow, Istanbul, etc.) and elsewhere (Cairo, Beijing, Shanghai, Bombay, Mexico City, etc.). The whole project will last from 2008 to 2011.

Pollution over Paris

Pollution cloud over Paris, leading to a significant drop in visibility.
The study of particulate pollution in the Île-de-France region is the focal point of the project, including the organisation of a large-scale experimental campaign to better understand and quantify the sources of particulate pollution. This campaign should enable a very fine characterisation of the organic fraction of particles, the formation pathways of which are the least well known, but whose health impact is high. The Île-de-France region was chosen as the study area because of its high pollution load, the strong contrast between its urban and rural regions, the presence of a strong scientific community and the presence of a dense air quality monitoring network (AIRPARIF). The observations collected will allow an evaluation and an improvement of the French models used for the simulation and the forecast of the atmospheric pollution, at the scale of the region and at the national scale (Prévair system).

Dates and locations

Two field campaigns are planned in the Paris region, in July 2009 and during the winter of 2009/2010, each lasting one month.

Means deployed

During the campaign, the following will be carried out

• ground observations at two sites, one urban (at the Laboratoire de l’Hygiène de la Ville de Paris in the 13th arrondissement) and one suburban (at the SIRTA of the IPSL at the École Polytechnique) ;
• and airborne observations, with about ten flights of the French ATR-42 aircraft, operated by the SAFIRE unit, in the pollution plume of the agglomeration.
• An important and innovative set of instruments will be implemented by the French and European partners, which will allow a very detailed and high frequency chemical characterization (from a few minutes to a few tens of minutes) of fine aerosols and their gaseous precursors.

Support

The project is supported by the European Community (FP7, Megacities Call) and by INSU via the LEFE programme.

Partners

23 institutions from 13 European countries are participating. The project leader is the Danish Meteorological Institute (DMI). The French contribution is coordinated by the CNRS.
European laboratories involved in the field campaign in Ile-de-France: Paul Scherer Institut (Villingen, Switzerland), Institut für Troposphärenforschung (Leipzig, Germany), University of Patras (Greece), University of Helsinki (Finland), Max-Planck Institut für Luftchemie (Mayance, Germany).

French laboratories involved
LISA/IPSL (Créteil), LSCE/IPSL (Gif-sur-Yvette), GAME/CNRM (Toulouse), LaMP/OPGC (Clermont-Ferrand), LGGE/OSUG (Grenoble) and SAFIRE (Toulouse)