Eurosim : simulating the future of the European cities
The aim of the model is :
Main specificities are :
- To simulate the past evolution of the European system
of cities (population and wealth) from 1950 to 2000 in order to identify the main trends of urban change
- To test scenarios of future evolution for 2000-2050 in order toexplore the possible futures of this system of
cities according to different hypotheses on the European demographical
and political context
- An initial situation which corresponds to an already
well shaped urban pattern (Europe in 1950). Thus, this model focuses
on evolution and change rather than on the emergence of a structure.
- As a consequence, the number of network functions are more numerous
and diversified than in the other applications.
Running of the model
About 100 simulations have been run. They correspond to three stages :
1- Testing the sensitivity of the model :
2- Calibrating the model using the period 1950-1990
- To events
- To variations in the exogenous variables (demographical and economical)
- To initial conditions
- To variations in the values of the key parameters
A hierarchical method is adopted: the most aggregate level is first calibrated
, and then the other levels are considered. As for most dynamic complex models,
the aim is more to get a general insight in the possible past and future
evolutions of cities than to reproduce exactly the observed values.
3- Testing different scenarios on the future evolution of the
European urban system
The relative dynamics of a city are directly related to the mechanisms
of exchange formalized in the model, but the change in total population
will also depend on the global context in which the city is functioning.
The scenarios concern two dimensions of this context:
- The demographical context : two extreme situations have been
explored, the first corresponding to a dynamic Europe opened to
foreign immigration and the second one to a closed and declining Europe.
The formalization of these contexts goes through the exogenous variables.
- The political context : again two extreme situations have been explored,
the first corresponding to an open Europe with no barriers between
countries or regional blocks and the second to the existence of barriers
between Eastern and Western blocks, reducing the possibilities of exchange
between cities. The key parameter “barrier” is used to formalize these
The EUROSIM model was developed in the framework of
TIGRESS (European project directed by Nick Winder)