Progress beyond the state-of-the-art



For the past few hundred years, human populations have been clustering in increasingly large settlements. In 2007, for the first time in history, the world’s urban population will exceed the rural population (UN-HABITAT, 2006). At present, there are about 20 cities worldwide with a population of 10 million or greater, and 30 with a population of exceeding 7 million. These numbers are expected to grow considerably in the near future. Such coherent urban areas with more than about 5 million people are usually called megacities (although there is no formal definition of a megacity at present). In Europe there are six major population centres that clearly qualify as megacities: London, Paris, the Rhine-Ruhr region, the Po Valley, Moscow, and Istanbul (Figure 1).

Megacities and heavily urbanized regions produce a large fraction of the national gross domestic product (GDP) (e.g. London, Paris and Mexico City account respectively of 19.9, 27.9 and 26.7% of the corresponding national GDP (OECD, 2006)). Human activities in megacities lead to serious challenges in municipal management, such as housing, employment, provision of social and health services, the coordination of public and private transport, fluid and solid waste disposal, and local and regional air pollution. This project focuses on the latter, spanning the range from emissions to air quality, effects on regional and global climate, and feedbacks and mitigation potentials. The project will take into account the different features and growing trends that characterize cities located in developed and developing countries to highlight their present and future effects on local to global air quality and climate.

Identification of problems to be solved

Our hypothesis is that megacities around the world have an impact on air quality not only locally, but also regionally and globally and therefore can also influence the climate of our planet. In Figure 2 a schematic description of how megacities, air quality and climate interact is presented. Some of the links shown have already been considered by previous studies and are reasonably well-understood. However, a complete quantitative picture of these interactions is clearly missing. Understanding and quantifying these missing links will be the focus of MEGAPOLI.

Worldwide megacities (Source UN, 2002)

Figure 1: Worldwide megacities (Source UN, 2002).

FP7 EC MEGAPOLI, 2008-2011