Are two earthquakes better than one? How earthquakes in two different regions affect risk judgments and preparation in three locations.

Abstract

Research has shown experiencing a single disaster influences people's risk judgments about the hazard. However, few studies have studied how multiple disasters in different locations affect risk judgments. Following two earthquake sequences in two different regions of Aotearoa New Zealand, this study examined earthquake risk judgments, non-fatalism and preparation. The research was done in two cities near to one of those sequences (Christchurch in Canterbury, Wellington near Cook Strait) and in one city distant from both events (Palmerston North). Judgments of earthquake likelihood were higher after the Cook Strait earthquakes than before in Christchurch and the rest of New Zealand, but not in Wellington, where the baseline risk was high. However, participants in all cities saw the risk as more real, plausible, and important after these earthquakes, particularly in Wellington. Preparations following the earthquakes were also higher in Wellington and Christchurch (where non-fatalism was highest) than in Palmerston North. Causal attributions for (not) preparing differed across the three cities, as did non-fatalism. These findings suggest that the Christchurch and Cook Strait earthquakes had a combined effect on citizens' perception of the risk, particularly in Wellington. It may be possible to create a vicarious experience using disasters in other countries. An example is when the Fukushima cascading disaster in Japan affected risk judgments about nuclear power plants as far away as Germany. A key issue is understanding what factors lead people to see a distant event as relevant to their own risk from the same hazard, as occurred with Fukushima and the Christchurch earthquakes.