Climate change could challenge the downward trend of large-scale fatal disasters in New Zealand.
A University of Otago study in Wellington analysed sudden events in New Zealand between 1900 and 2015 that caused at least 10 deaths.
Its findings were published in the Australian and New Zealand Journal of Public Health.
It found a sharp drop in the number of fatal large-scale events, from 21 between 1900 and 1919, to just three between 2000 and 2015.
It also found that earthquakes were our most lethal natural disaster, with an average of four deaths a year over the 115-year period covered by the study.
Public health researcher Professor Nick Wilson, who led the research with associate professor George Thomson, put the drop down to safer transportation.
People had found much safer ways of getting around, he said.
"They were largely driven by the reduction in transport-related events. So, ships sinking, trains crashing, aircraft crashing.
"This transportation category reduction probably reflects a large number of factors, such as improvements in vehicle design, marine and aircraft navigation systems, weather forecasting and safety systems in general."
But the downward trend may not last forever, Wilson said.
"In the future, it's still uncertain, because climate change does seem to be happening rapidly.
"So there could even be those sort of risks that New Zealand has to think about in the future."
