D E S C R I P T I O N O F W O R K - MEGAPOLI - Dmi

MEGAPOLI 212520
for 40% of Italy’s GDP. It is home to 37% of the country’s industry, about 55% of livestock, and
35% of the country’s agricultural production. The Po valley is therefore exposed to substantial
emission loads. The atmospheric circulation of the Po valley is characterised by the strong
modification of synoptic flow due to the high mountains that surround the valley on three sides. The
local atmospheric circulation features, dominated by calms and weak winds, favour the
development of critical pollution episodes. Milan city and its surrounding urban area is located in
the flat central part of the Po river basin. The core of Milan urban area, roughly coincident with its
province, accounts for 3.7 millions inhabitants, while the commuting area includes around 7 million
people (OECD, 2006). During the last decades, the urbanisation of the surrounding region has been
enhanced by the re-settlement of part of the population from the city core to the surrounding region.
The Rhine-Ruhr area is situated in the state of North Rhine-Westphalia, in Germany’s industrial
heartland. It is home to cities like Bochum, Bottrop, Dortmund, Duisburg, Essen, Gelsenkirchen,
Köln, Leverkusen, Solingen and Wuppertal, covers an area of about 10.000 km 2 and has a total
population of more than 10 million people. With frequent west and south-west winds, the Rhine-
Ruhr region is also downwind of other European megacities (London and Paris) and impacted by
emissions from the Netherlands. Therefore, this region is not only exposed to “home made” new
emissions but also to aged air from neighbouring regions. Due to the mostly hilly terrain of the
region, air pollution and local climate are very heterogeneous and quite locally influenced.
Figure 5: Population density in EU Figure 6: Loss in life expectancy (months)
for 2003 (Source Eurostat). attributable to exposure to anthropogenic PM2.5
for year 2000 emissions (Source: EC, IIASA)
The four megacity areas identified above have different urban features and cover a wide range of
topography, climate and atmospheric circulation conditions, providing a variety of different test
cases for the evaluation and application of the MEGAPOLI modelling tools and the assessment of
mitigation scenarios.
Many fast-growing cities are located within and nearby Europe (e.g. Moscow, Cairo and Istanbul)
and can directly affect European air quality and climate for example in the climate-change sensitive
Mediterranean Basin. Moreover, the largest megacities with populations exceeding 20 million and
showing continuous growing tendency, are located in developing countries in other continents. In
those megacities air pollution abatement policies are still in their infancy and their emissions are
expected to have a large effect on regional and global air quality and also climate. For these reasons
the analysis of megacities effects at regional scale (WP1, WP4 and WP5) will include the 2nd level
megacities listed in Figure 4. Mexico City will be investigated in detail because of the availability
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