Citation

Louf R, Barthélemy M. Sci. Rep. 2014; 4: e5561.

Affiliation

Institut de Physique Théorique, CEA, CNRS-URA 2306, F-91191, Gif-sur-Yvette, France.

Copyright

(Copyright © 2014, Nature Publishing Group)

DOI

10.1038/srep05561

PMID

24990624

PMCID

PMC4080200

Abstract

The recent availability of data for cities has allowed scientists to exhibit scalings which present themselves in the form of a power-law dependence on population of various socio-economical and structural indicators. We propose here a stochastic theory of urban growth which accounts for some of the observed scalings and we confirm these predictions on US and OECD empirical data. In particular, we show that the dependence on population size of the total number of miles driven daily, the total length of the road network, the total traffic delay, the total consumption of gasoline, the quantity of CO2 emitted and the relation between area and population of cities, are all governed by a single parameter which characterizes the sensitivity to congestion. Our results suggest that diseconomies associated with congestion scale superlinearly with population size, implying that -despite polycentrism- cities whose transportation infrastructure rely heavily on traffic sensitive modes are unsustainable.

Language: en