Mapping Landslide Risk of the World

Landslides are global hazards that cause huge economic and human losses around the world every year. The study of landslide at global scale is critical to disaster reduction and hazard risk management of world landslide disasters. Previous work on landslide mapping at the global scale was accomplished by prerequisite geographic data such as real-time precipitation, population distribution, and human casualty dataset. By combining the traditional methods to map global landslide susceptibility, this work has quantified the number of landslide events based on landslide threshold for the after-real-time 3-h resolution TRMM precipitation data from 1998 to 2012. To compensate the limited sample years with the available annual landslide records, information diffusion theory is applied to estimate the annual numbers of expected landslide events. Expressed as the annual expected number of landslide events, the resulted global landslide hazard map is validated by the global landslide hazard hotspot map developed by the Norwegian Geotechnical Institute (NGI). Population vulnerability and fatality risk of landslide hazards are calculated at the global scale by combining LandScan global population data and the global landslide fatality inventory. Different from global landslide hazard maps, populous regions near plate margins and corridors or the transition zones from plain to the mountain areas have higher landslide fatality risk. Himalaya Rim, Central and South America, Italy, and Iran are identified as high landslide fatality risk regions. Developing countries with large portions of mountain territory bear the highest fatality risks around the globe.