Calculated Risk: Why People Live in Disaster Zones

People are willing to put daily pleasure ahead of the threat of long-term disaster when selecting where to live, research finds.

Humans may be willing to put daily pleasure ahead of the threat of long-term disaster when selecting where to live, a new international study suggests.

Study co-author Professor Ben Newell, of the University of NSW, said the research examined how people would react to being told of a predicted increase in the risk of natural disasters with climate change.

Professor Newell, from the School of Psychology, said it was surprising how little weight participants in the study gave to disaster threat.

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"Even when the long-run value of living in the place is lower than staying safe, people still persisted with these riskier choices," he said.

"It is like living by the coast is fine most of the time, but are you willing to risk that chance of inundation?"

It was previously assumed more information would lead people to reduce their exposure to risk.

However, Professor Newell and his colleagues from the UK and Israel, who published their research today in Nature Climate Change, found the opposite was true.

Information after a disaster could have the "paradoxical effect of changing people's perception of risk in the opposite direction", Professor Newell said.

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"There was a tendency after a disaster had hit for some people to move into that area, which is consistent with a kind of thinking that lightning isn't going to strike in the same spot twice," he said.

Studying risk in ‘microworld'

For the study, the research team created a "microworld" that contained three villages with varying levels of risk attached to living there.

The 180 participants earned points for where they chose to live, but also lost points when a catastrophe hit their dwelling.

One region of the "microworld" was safe: catastrophes never occurred, but the points for choosing to live there were modest.

A second region offered more points, but rare catastrophes occurred which affected a small portion of the dwellings.

A third region had very rare catastrophes, which affected almost all the dwellings, but individual homeowners faced the same probability of disasters as in region two.

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The participants were given accurate information about the risk of catastrophe in each region.

However, the way they heard about disasters was varied in a way designed to mimic three different ways people might have access to information in real life - personal experience only, local information sources only, or additional information from afar via the media or authorities.

"The condition where people tolerated more risk was where they could see the risk from all of the different regions," Professor Newell said.

"You get the sense that most of the time things are okay so they tolerate this possibility of a rare disaster occurring."

However, when people were only given the factual data and were not aware of what was happening globally, they were less likely to tolerate the risk, he said.

Importance of communicating threats

Professor Newell said the findings highlighted the importance of how trends and the accumulation of disaster events were communicated.

"Saying that it is a ‘one in a 100-year storm' is not the best way to get across the accumulation of the risk," he said.

"We need to emphasize the occurrence rather than the non-occurrence of these events."

This could mean a shift to risk summaries that focused on long time intervals, as it would more likely include multiple disasters and emphasize the increasing prevalence of disasters.

However, Professor Newell said he was wary of drawing too much from the research.

"My biggest concern is jumping from a result in our experimental world to what the implications are for major societal disasters," he said.

"But at least it sheds some light on how people combine a description of a risk with the outcomes they perceive day-by-day in their experience."

This originally appeared on ABC Science Online.

A couple walk through the flood waters pushed up from Lake Pontchatrain by Hurricane Ike near the Marina on Sept. 12, 2008 in New Orleans, Louisiana.

Although deadly, Hurricane Isaac scourged Louisiana with less ferocity than Hurricane Katrina did seven years ago. Katrina was one of American history's deadliest and costliest natural disasters. Part of what made Katrina such a tragedy was the inadequate emergency response from authorities. However, as intense as the outcry over the response to Katrina was, it pales in comparison to the repercussions of when one of history's deadliest storms struck what is now Bangladesh. Bangladesh was a part of Pakistan at that time, but the people of East Pakistan, as the region was called, suffered discrimination from the western portion of the nation and revolution was smoldering. The flames of nationalism and rebellion were fanned by the high winds of the massive Bhola cyclone which rushed in from the Bay of Bengal on November 10, 1970. The Pakistani government was criticized by locals and in the international media for failure to provide adequate disaster relief to East Pakistan, which may have contributed to the 300,000 to 500,000 people who perished in the storm and its aftermath. Soon after the cyclone, the storm of East Pakistan's outrage built into a war that tore Pakistan apart. The torment of war raged on until Bangladesh emerged as an independent nation from the flood of bloodshed that was the Bangladesh Liberation War. Throughout history massive storms have toppled human ambitions and left suffering and death in their wake. Particular natural disasters stand out from the line up of perpetrators as particularly devastating natural born killers.

The Day America Burned The wildfires that incinerated stretches of the American west this year were huge, but relatively few people lost their lives. On October 8, 1871 more people died in the flames of a wildfire than on any other day in recorded human history. On that day the Peshtigo Fire started in the forests of Wisconsin and was spread by a strong wind. The blaze quickly grew as it fed on trees left parched by a summer drought. The flames weren't extinguished until after they had snuffed out the lives of 1,200 – 2,500 people. The exact number is unknown because local records were also destroyed. The entire town of Peshtigo was consumed, leaving few to identify the charred corpses. On the same day, the Great Chicago Fire reduced much of the Windy City to ashes. Though Mrs. O'Leary's cow was later cleared of any culpability, the story of a kicking cow starting the fire became part of the legend surrounding the blaze that killed 300.

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