Applications‎ > ‎

Europe 1950-2050

Eurosim : simulating the future of the European cities

The aim of the model is :

  1. 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
  2. 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
Main specificities are :
  • 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 :
  • To events
  • To variations in the exogenous variables (demographical and economical)
  • To initial conditions
  • To variations in the values of the key parameters
2- Calibrating the model using the period 1950-1990

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 different situations.

The EUROSIM model was developed in the framework of TIGRESS (European project directed by Nick Winder)