It’s harder for poor countries to respond to natural disasters. We should help them be better prepared before hurricanes and earthquakes strike.

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Hurricane Katrina, Australian floods, Japan’s 2011 earthquake and tsunami: Even the wealthiest, best-prepared countries can experience large-scale damage and destruction when natural disasters strike.

But the situation is much worse in poor countries without the resources to protect their population or economy against catastrophes. Building codes are lacking or poorly enforced, and infrastructure is insufficient to send out information before a disaster, or assist victims promptly after it hits. The 2010 earthquake in Haiti starkly illustrated what happens when natural disasters strike an unprepared and poor country.

Oftenpoor countries only make the pages of our newspapers when disasterstrikes. Tragic images prompt us to give generously to assist those who have been hurt or made homeless. But what if we adopted an “ambulance at the top of the cliff” approach and tried to increase the resiliency of developing countries to natural disaster?

Hurricanes, earthquakes, and floods impose an economic toll that can disrupt and undermine a fragile country for a long time. This cost is growing. According to the reinsurer Munich Re, direct economic losses from natural catastrophes amounted to $1.6 trillion from 2001 to 2011. Small island economies like St. Lucia and Samoa have suffered high losses to productivity because of disasters. Nature can impose a roadblock to the growth that lifts people out of poverty.

Costs from natural disasters are increasing largely because more people choose to live in harm’s way. This trend, combined with the expectation of some events becoming more extreme because of changes in climate patterns, challenges the human capacity to adapt. In an innovative paper for Copenhagen Consensus 2012 released today, Professors Howard Kunreuther and Erwann Michel-Kerjan from the Wharton School at the University of Pennsylvania propose a series of concrete actions that would reduce the vulnerability of poor nations to such large-scale catastrophes.

They propose investments in four risk-reduction measures. The first three proposals are designed to better protect against damage and loss of life from earthquakes, floods, and hurricanes, and the final one is intended to more generally increase the resilience of communities.

First, the authors propose designing schools that can withstand earthquakes to reduce damage and also the number of fatalities to children, teachers and other staff. Retrofitting the schools in all 35 most-exposed countries around the world would save the lives of 250,000 individuals over the next 50 years. Costs vary dramatically from country to country: In the Solomon Islands it would cost just $36 million to retrofit schools with cumulative total benefits worth $187 million, but for all other countries the benefits are dramatically lower, meaning that any program of global reach would probably pay back less than the initial investment.

Kunreuther and Michel-Kerjan’s second proposal is to invest in community flood walls and elevated homes to protect areas subject to floods. It would cost $5.2 trillion to elevate by one meter all houses subject to flooding in the 34 countries most susceptible to this hazard and another $940 billion to build walls around the relevant communities in all 34 countries. The most cost-effective approach would be to invest $75 billion into building flood walls around some of these communities. Kunreuther and Michel-Kerjan calculate the benefits over the next 50 years as $4.5 trillion, making the benefits a remarkable 60 times higher than the costs. Those benefits would mostly come from reduction in damages, though the walls  would also save 20,000 lives.

Thirdly, they propose strengthening the roofs of houses in countries with high exposure to hurricanes and cyclones to reduce losses from wind damage. This would cost $951 billion in the 34 countries most prone to high wind events, with benefits ranging between two and three times this amount. This measure would save 65,700 lives over the next 50 years.