Volcanic eruptions are powerful natural events which impact strongly on society. As human populations grow and expand into volcanically active areas, their exposure and vulnerability to volcanic hazards is also increasing. Of all volcanic hazards, ashfall is the most likely to impact society because of the large areas affected. The widespread dispersal of ash can cause large scale disruption of vital infrastructure services, aviation, and primary production. This report summarises the formation of volcanoes, lists the volcanic hazards to society and critical infrastructure and, considering the importance of electric power infrastructure to maintaining day-to-day activities, provides some recent literature on the effects of volcanic ashfall hazards to electric power infrastructure. Finally, some brief comments are made about the need for quantitative volcanic risk assessment to better inform catastrophe models used in the re/insurance industry.
Figure 1. The three tectonic settings where volcanism occurs (USGS, 2015).