Tag Archives: natural disaster risk

The Cure for Catastrophe?

On August 24, 2016 – just a few weeks ago – an earthquake hit a remote area of the Apennine mountains of central Italy in the middle of the night. Fewer than 3000 people lived in the vicinity of the strongest shaking. But nearly 1 in 10 of those died when the buildings in which they were sleeping collapsed.

This disaster, like almost all disasters, was squarely man-made. Manufactured by what we build and where we build it; or in more subtle ways – by failing to anticipate what will one day inevitably happen.

Italy has some of the richest and best researched disaster history of any country, going back more than a thousand years. The band of earthquakes that runs through the Apennines is well mapped – pretty much this exact same earthquake happened in 1639. If you were identifying the highest risk locations in Italy, these villages would be on your shortlist. So in the year 2016, 300 people dying in a well-anticipated, moderate-sized earthquake, in a rich and highly-developed country, is no longer excusable.

Half the primary school in the town of Amatrice collapsed in the August 24th earthquake. Very fortunately, it being the middle of the night, no children were in class. Four years before, €700,000 had been spent to make the school “earthquake proof.” An investigation is now underway to see why this proofing failed so spectacularly. If only Italy was as good at building disaster resilience as mobilizing disaster response: some 7000 emergency responders had arrived after the earthquake – more than twice as many as those who lived in the affected villages.

The unnatural disaster

When we look back through history and investigate them closely we find that many other “natural disasters” were, in their different ways, also man-made.

The city of Saint-Pierre on the island of Martinique was once known as the “little Paris of the Caribbean.” In 1900 it had a population of 26,000, with tree-lined streets of balconied two and three story houses. From the start of 1902 it was clear the neighbouring volcano of Mont Pelée was heading towards an eruption. The island’s governor convened a panel of experts who concluded Saint-Pierre was at no risk because the valleys beneath the volcano would guide the products of any eruption directly into the sea. As the tremors increased, the Governor brought his family to Saint-Pierre to show the city was safe, and therefore, likely all but one of the city’s inhabitants, died when the eruption blasted sideways out of the volcano. There are some parallels here with the story of those 20,000 people drowned in the 2011 Japanese tsunami, many of whom had assumed they would be protected by concrete tsunami walls and therefore did not bother to escape while they still had time. We should distrust simple notions of where is safe, based only on some untested theory.

Sometimes the disaster reflects the unforeseen consequence of some manmade intervention. In Spring 1965, the U.S. Army Corps of Engineers completed the construction of a broad shipping canal – known as the Mississippi River Gulf Outlet (“Mr Go”) linking New Orleans with the Gulf of Mexico. Within three months, a storm surge flood driven by the strong easterly winds ahead of Hurricane Betsy was funnelled up Mr Go into the heart of the city. Without Mr Go the city would not have flooded. Four decades later Hurricane Katrina performed this same trick on New Orleans again, only this time the storm surge was three feet higher. The flooding was exacerbated when thin concrete walls lining drainage canals fell over without being overtopped. Channels meant for pumping water out of the city reversed their intended function and became the means by which the city was inundated.

These were fundamental engineering and policy failures, for which many vulnerable people paid the price.


My new book, “The Cure for Catastrophe,” challenges us to think differently about disasters. To understand how risk is generated before the disaster happens. To learn from countries, like Holland, which over the centuries mastered their ever-threatening flood catastrophes, through fostering a culture of disaster resilience.

Today we can harness powerful computer technology to help anticipate and reduce disasters. Catastrophe models, originally developed to price and manage insurance portfolios, are being converted into tools to model metrics on human casualties or livelihoods as well as monetary losses. And based on these measurements we can identify where to focus our investments in disaster reduction.

In 2015 the Tokyo City government was the first to announce it aims to halve its earthquake casualties and measure progress by using the results of a catastrophe model. The frontline towns of Italy should likewise have their risks modeled and independently audited, so that we can see if they are making progress in saving future lives before they suffer their next inevitable earthquake.


The Cure for Catastrophe is published by Oneworld (UK) and Basic Books (US)

Risk and the City

I recently presented at a two-day seminar organized by the Geneva Association in collaboration with the XL Group with a key theme of “urban risk”—a pressing topic, as more than 50 percent of the world’s population currently lives in cities. By 2030, the proportion will have risen to 60 percent.

I came to the meeting with a presumption that as cities expand, the risk from natural disasters will fall for a few different reasons:

  • Higher concentrations of people and value in urban areas motivates better flood defenses and more effective drainage systems than in rural areas.
  • Tall buildings have more of their value out of reach of floods.
  • City buildings are much more likely to have been designed by a structural engineer who has accounted for risks such as wind damage or earthquake shaking.
  • Friction from buildings at the boundary layer slows down hurricane winds.

These are all good reasons why urbanization should be a powerful force for risk reduction.

Blackout in New York City during Hurricane Sandy. Credit: David Shankbone

Conversely, here are ten reasons risk can be higher in cities:

1)    Desire to be close to the center of the city inevitably raises land values, and encourages land to be “reclaimed” for development, while still remaining susceptible to flooding, liquefaction, and amplified earthquake shaking.

2)    High central business district land values encourage the use of underground space for storing some of the most valuable and mission-critical equipment, raising the costs when the city floods.

3)    Land in the city that is abandoned as too landslide-prone or too flood-prone gets built on anyway by informal settlements, which then add to the urban risk.

4)    The September 11, 2001 attacks and the 1985 Mexico City earthquake highlighted situations where people living or working in high-rise city center buildings were at much greater risk than those beyond the city or in the suburbs.

5)    While in wealthy countries structural engineers ensure that taller buildings meet construction standards, in developing countries many midrise buildings are constructed without engineers.

6)    When the urban flood defenses do break, such as New Orleans in 2005 or in Nagoya, Japan in 2000, the consequences are much worse than if the defenses had not been constructed, because some cities have been developed as if there is no risk.

7)    Hazards and buildings interact in complex ways. Urban tornadoes create a debris field that expands the width of the damage zone beyond the highest winds. Urban storm surges and hurricane winds also turn building debris into hazard agents.

8)    Cities are totally dependent on electrical power. When the power goes out, all kinds of functions stop. For example, during Superstorm Sandy, many disabled people were stranded in their apartment buildings in the absence of working elevators.

9)    Cities can show reduced levels of social support in disasters, as seen in the higher casualty rates in Paris during the August 2003 French heat wave.

10)   Lastly, cities are typically located on a waterfront where they inevitably confront frontline water hazards such as storm surge or tsunami.

So, does that all add up to higher levels of risk?

To answer that question, we would need to perform a controlled study of two regions: one with a big city and one without, to model the comparative loss ratio for people and property across all perils. Factors such as economic wealth levels would need to be taken into consideration.

What we know for sure is the risks of a big city are different to those of rural areas. Going forward, we will inevitably see an increasing proportion of big urban disasters like those of the last decade in New Orleans, Port au Prince, Christchurch, and New York.