World Disasters Report 2010 - International Federation of Red Cross ...

CHAPTER 2
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The index is most heavily influenced first of all by values of exposed assets and their
degree of vulnerability. Figure 2.4 shows that Tokyo is, by far, the city at highest risk,
followed by San Francisco. Of the 20 highest-risk cities in the index, 17 are in highincome
countries. This makes sense given that the index is trying to gauge the risk for
insurers and thus the value of exposed assets, which is greater in high-income countries
and is an important factor in understanding the potential for economic losses in a
disaster.
The index shows that for large disasters, the economic costs are often much higher
in high-income nations and much of this will be in urban areas, but this is not
an indicator of how many people faced serious economic losses and did not have
insurance. The index does not at all convey the reality that very large numbers of
low-income urban dwellers can lose their homes and most or all their assets from
disasters; the total monetary value of this is small but the hardships on individuals
and families are immense.
Vision two: Flood exposure in port cities
An index published by the Organisation for Economic Co-operation and Development
ranks 136 port cities of over 1 million population with high exposure to one-in-100year,
surge-induced flood events. It looks at the exposure of population and assets, in
2005 and those predicted in 2070. Future predictions account for population growth,
urbanization, ground subsidence and climatic changes.
Population growth and investment in urban infrastructure are the most important
drivers for increase in exposure to surge-induced floods. This is especially true in developing
regions, which are expected to have large growth. Overall, without any increase
in water levels, asset exposure could grow eight-fold. Climate changes, as predicted
by the Fourth Assessment Report of the Intergovernmental Panel on Climate Change,
including increased storm intensity and sea-level rise, also influence increased exposure.
The influence of human-induced subsidence due to shallow groundwater extraction
is especially important in deltaic cities that are rapidly developing.
The index overwhelmingly shows that cities in Asia have the highest exposure to surgeinduced
flooding now and in the future. Of the 20 cities with the highest population
exposure in 2005, half are in low- and middle-income nations in Asia. In real numbers,
out of the total 38.5 million people currently exposed, 65 per cent of them live in
Asian cities. Figure 2.5 shows the top 20 world port cities with exposed populations
in 2005. In the 2070s, the index predicts that 17 out of the 20 cities with the highest
population exposure will be in present-day low- and middle-income countries and
14 out of 20 of the cities will be in Asia (four in China and two in Bangladesh). Asia’s
increasing dominance in terms of population and asset exposure is a result of increased
urbanization and economic growth during the period, compared with other regions.