Macromotives and microbehaviors: Climate change constraints and passenger mobility scenarios for France

The reduction of greenhouse gas emission is now firmly established at the top of the public policy agenda, to the extent that it is increasingly often presented as one of the major constraints which will be placed on activities, particularly in the transport sector. This sector creates large amounts of greenhouse gases and is characterized by the highly decentralized nature of its emissions which are the outcome of the travel decisions taken by billions of individuals. The collective problem is therefore created by a multitude of individual behaviors. If travel choices are constrained in an attempt to solve this collective problem, we need an understanding of the economic bases of individual behaviors. With this in view, this paper begins by presenting the macroscopic impacts of a number of sustainable travel scenarios in France in the year 2050. It then shows the changes in trends which accompany the necessary changes in individual travel behaviors. Some of these changes in trends amount to breaks with the past which will be far from easy to implement.