Ten years ago, on October 13th, 2009, the United Nations General Assembly designated October 13th as the International Day for Disaster Reduction. The aim was to have annual observance of the day as a means to foster a worldwide culture of natural disaster reduction. Natural disasters happen, but the aim was to promote measures that would include prevention, mitigation and preparedness, and to encourage private citizens and organizations, together with governments, to participate in creating more disaster-resilient communities and countries.

Obviously there will be floods, earthquakes, volcanoes, hurricanes and typhoons, and we do not yet have the technical means to prevent them or to reduce their severity. But there are measures we can take, sensible measures, that can lessen the impact they have on people's lives. Some lessons have been learned the hard way. It is not good planning to site nuclear reactors in areas prone to earthquakes and tsunamis. It is not sensible to allow low-lying buildings to proliferate on flood plains. There might be fertile soil on the slopes of dormant volcanoes, but villages located there will be at risk from subsequent eruptions. All of these require a certain amount of common sense combined with intelligent analysis.

We can also plan ahead, and make our structures less prone to the effects of such natural disasters as do occur. When I built a house in the Florida Keys, it had to be on concrete stilts 13 feet about the century's mean flood level. I sold it long ago, but was gratified to see from satellite imagery that it had survived more or less intact after a nearly direct hit from Hurricane Irma in 2017.The great Japanese earthquake of 1923 had a magnitude of 7.9 and devastated Tokyo, killing 100,000 people. Frank Lloyd Wright's recently built Imperial Hotel survived among the rubble around it, largely because the extra steel in the frame prevented a roof collapse. He had sought to make it earthquake-proof.

The San Francisco earthquake of 1906 destroyed nearly 500 city blocks, killed 3,000 people, and left 400,000 homeless. The earthquake there in 1989 killed 63 people. Hurricanes and typhoons that kill hundreds of thousands in poor countries might kill dozens, or perhaps hundreds, in developed countries. Part of this is down to preparedness, to having tested rapid-response systems, with personnel and vehicles at the ready. Developed countries have the wealth and the infrastructure in place to bring this into play. This is one reason why storms that destroy communities in the Caribbean tend to cause damage in the US that can be contained and rapidly rebuilt.

We have early warning systems in place, constructed by developed countries, but of benefit to poorer ones, too. We can see hurricanes forming and track their probable course, alerting those in their path to board up or evacuate. We often can anticipate volcanic eruptions by monitoring increases in activity a few days in advance. We are not yet adept at having the same success in predicting earthquakes, but the seismic sciences are advancing. And following the Boxing Day tsunamis of 2004 that killed an estimated 228,000 people in 14 countries, we now have sensors out at sea to detect earthquakes and are able to issue tsunami alerts that send people to seek higher ground away from shores.

The lesson we take from all of this is that the greatest factor in aiding prevention, mitigation and preparedness is wealth. Rich countries do not suffer the catastrophic consequences that blight poorer ones when natural disasters occur. As poorer countries become richer, as most are now doing, they become more able to cope with disasters. People in rich countries can help, of course, with aid and supplies, medical assistance and food, but this is dealing with disasters after the fact, rather than putting in place the infrastructure that makes them less disastrous in the first place. The single biggest step a poor country can take to make it resilient to disasters is to become a rich country. And the way to do that is through trade and exchange, as the rich ones did.