The approach, called "ensemble modelling," allows the researchers to better understand where risks are greater due to relative vulnerability of communities, or their location in relation to identified likely earthquake impacts.
"Traditional assessments of seismic risk focus primarily on improving understanding of earthquake hazard, in terms of potential ground shaking but for contingency planning, it is the potential impacts of an earthquake that are of more importance. Our method provides critical information on the likelihood, and probable scale, of impacts in future earthquakes. We hope this can help better inform how governments and aid agencies direct limited disaster mitigation resources, for example how they distribute resources geographically," Dr. Tom Robinson, Durham University Department of Geography, said.
Together with Nepal's National Society of Earthquake Technology, the team modeled fatalities from 90 different scenario earthquakes and established whether or not the impacts were specific to a certain scenario.
"The results showed that for most districts in Nepal similar impacts occurred irrespective of the scenario earthquake and that impacts were typically closer to the minimum rather than the worst-case scenario. This suggests that planning for the worst-case scenario in Nepal may place an unnecessarily large burden on the limited resources available. Our results also showed that the most at-risk districts are predominantly in rural western Nepal and that there are around 9.5 million Nepalese people who live in districts that are at a higher seismic risk than the capital, Kathmandu," Dr. Robinson said.
The novel approach is not only relevant to Nepal, it can be applied anywhere, to help inform earthquake disaster risk reduction planning.
The findings of the study were published in Proceedings of the National Academy of Sciences on September 24.