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.