Modeling flood risk

A major focus of risk modeling work in Risk, Policy and Vulnerability (RPV) has been on flood risk, which is often considered the dominant extreme event hazard.

Flood in Pakistan © Oxfam International | flickr Creative Commons License

Flood in Pakistan

Based on analysis with many leading colleagues in the field, RPV focused on providing global and regional perspective on changing rainfall-driven flood risk under climate change for the early 21st century [1]. 

The findings show that the impacts of climate change on flood characteristics are highly sensitive to the detailed nature of those changes, and that presently there is only low confidence in numerical projections of changes in flood magnitude or frequency resulting from climate change.

Yet, even without climate change, more people will be flood-exposed over time due mainly to increases in population and capital in vulnerable areas.

The authors project increased exposure from about 800 million people worldwide living in floodplains today (over 11% of global population) to 940 million by 2030, with the average number of people affected by floods each year rising from 70 to 86 million.

Population exposed to floods each year assuming constant hazard (in thousands of people per year, left and in percentage of total population, right). Annualized values in both absolute and relative terms are used.


[1] Kundzewicz ZW et al. (2013). Flood risk and climate change: Global and regional perspectives. Hydrological Sciences Journal 59(1).

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Last edited: 22 May 2014


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