Global toll. Researchers behind the hotspots study say maps with losses as a proportion of GDP can effectively compare regions facing disparate risks.

Our Dangerous Planet

A new analysis of natural disasters provides a comprehensive look at the relative risk facing poor and rich regions around the world.

The study, released Monday, calculated the local risks for six particular hazards – drought, earthquakes, volcanoes, cyclones, floods, and landslides – by combining populations for each gridpoint with the historical records of disaster frequency and subsequent losses. A similar analysis of loss proportional to gross domestic product (GDP) provided economic risks at each point on the map.

In 160 countries, the researchers found, more than 25% of the population resides in areas where their lives are at high risk. The analysis found Taiwan particularly dangerous, with 73% of its land exposed to three or four of the following hazards: flood, earthquakes, cyclones, and landslides. Although risk assessments are nothing new, "we're unique in the extent to which we've applied it globally to so many hazards," said Maxx Dilley, a scientist at the International Research Institute for Climate Prediction at Columbia University in New York City, a co-sponsor of the work along with the World Bank and other institutions.

The researchers acknowledge that their maps may not effectively reflect the risk of low-probability/high-impact events such as the 26 December South Asia tsunami. But team member Arthur Lerner-Lam, director of the Center for Hazards and Risk Research at Columbia, said that preparing for persistent risks allows hard-hit areas to cope with unexpected disasters, too. "A development agenda which deals with resiliency creates a better capacity to deal with the extreme events," said Lerner-Lam.

Researchers hope the work's GDP-adjusted maps will ease global assessment and give experts a way to compare, say, the risk of severe drought in Africa with floods in Southeast Asia. "A report like this could be used as a decision tool by [development] agencies as they make investment decisions in the future," said Kathleen Tierney, director of the Natural Hazards Research and Applications Information Center at the University of Colorado in Boulder.

Related sites
Natural Disaster Hotspots: A Global Risk Analysis
Center for Hazards & Risk Research at Columbia University