The vulnerability of the European air traffic network to spatial hazards

The 2010 eruption of the Eyjafjallajökull volcano had a devastating effect on the European air traffic network, preventing air travel throughout most of Europe for 6 days (Oroian in ProEnvironment 3:5–8, <CitationRef CitationID="CR17">2010</CitationRef>). The severity of the disruption was surprising as previous research suggests that this type of network should be tolerant to random hazard (Albert et al. in Nature 406(6794):378–382, <CitationRef CitationID="CR2">2000</CitationRef>; Strogatz in Nature 410(6825):268–276, <CitationRef CitationID="CR20">2001</CitationRef>). The source of this hazard tolerance lies in the degree distribution of the network which, for many real-world networks, has been shown to follow a power law (Albert et al. in Nature 401(6749):130–131, <CitationRef CitationID="CR1">1999</CitationRef>; Albert et al. in Nature 406(6794):378–382, <CitationRef CitationID="CR2">2000</CitationRef>). In this paper, we demonstrate that the ash cloud was unexpectedly disruptive because it was spatially coherent rather than uniformly random. We analyse the spatial dependence in air traffic networks and demonstrate how the combination of their geographical distribution and their network architectures jeopardises their inherent hazard tolerance. Copyright The Author(s) 2012