Nine of the ten countries with the highest displacement risk are in south and south-east Asia. Most of these countries regularly rank in the top ten in IDMC’s annual disaster-related displacement estimates, and some appear every year. This reflects the region’s large number of people exposed to sudden-onset hazards. Exposure, however, also drives displacement risk in upper middle-income countries such as China and high income countries such as the US. Large numbers of densely populated settlements in coastal areas, and on seismic fault lines and riverine basins across the US mean the country faces average annual displacement associated with the major hazards of more than 200,000 people. Vulnerability also plays a significant role. Eight of the ten countries with the highest displacement risk are in the lower middle-income group. As in the US, the size and density of populations exposed to hazards in India, China and Bangladesh results in high displacement risk, but it is pushed higher still by the numbers of people living in substandard buildings and with less resources to cope, which makes them more vulnerable. In comparison to the risk of economic loss from disasters, which in absolute terms is usually highest in high-income countries, absolute displacement risk associated with disasters is highest in low and lower middle income countries. The relative distribution of displacement risk – average annual displacement relative to population size – would be expected to be concentrated disproportionately in low and lower middleincome countries or small island states, but it is the case regardless of whether understood in absolute numbers or in relation to population size. While the large majority of countries with the highest displacement risk in absolute terms are in the low and lower middle income category, all top 10 countries in terms of displacement risk relative to population size are small island states, several of which are also low and lower middle income countries (see figure 1.23). This reflects the fact that vulnerability and limited capacity to reduce disaster risk tend to be the overriding factors in determining displacement risk. The two measures taken together reveal the extreme challenges these countries face. Our risk model can also be used to estimate the frequency and magnitude of displacement events associated with disasters with specific return periods. Results expressed in exceedance curves show the probability of a certain number of displacements being exceeded for any given return period. For a return period of 10 years, for example, Indonesia faces the displacement of at least 100,000 people as a result of earthquakes alone. At least another 700,000 people can be expected to be displaced by floods (see figure 1.24). Figure 1.23: Countries with largest modelled Average Annual Displacement (relative to population size) [PEOPLE PER 100,000 INHABITANTS] Source: IDMC, with UNISDR data 46 GRID 2017