The Spatial Structure of Transnational Human Activity

Recent studies have shown that the spatial structures of animal displacements and local-scale human motion follow Lévy flights. Whether transnational human activity (THA) also exhibits such a pattern has however not been thoroughly examined as yet. To fill this gap, this article examines the planet-scale spatial structure of THA (a) across eight types of mobility and communication and (b) in its development over time. Combining data from various sources, it is shown that the spatial structure of THA can indeed be approximated by Lévy flights with heavy tails that obey power laws. Scaling exponent and power-law fit differ by type of THA, being highest in refuge-seeking and tourism and lowest in student exchange. Variance in the availability of resources and opportunities for satisfying associated needs appears to explain these differences. Over time, the Lévy-flight pattern remains intact and remarkably stable, contradicting the popular idea that socio-technological trends lead to a "death of distance." Longitudinal change occurs only in some types of THA and predominantly at short distances, indicating regional shifts rather than globalization.