Tuesday, August 21, 2012

Flood risk ranking reveals vulnerable cities

Phys.org: A new study of nine coastal cities around the world suggests that Shanghai is most vulnerable to serious flooding. European cities top the leader board for their resilience.

These finding are based on a new method to calculate the flood vulnerability of cities, developed by a team of researchers from the Netherlands and the University of Leeds. The work is published in the latest edition of the journal Natural Hazards. The index does not just look at the likelihood of a city’s exposure to a major ‘once in a hundred years’ flood.

The researchers have been careful to include social and economic factors in their calculations too. The index incorporates 19 components, including measures of the level of economic activity in a city, its speed of recovery, and social issues such as the number of flood shelters, the awareness of people about flood risks, and the number of disabled people in the population. Several index components also look at the level of administrative involvement in flood management.

The researchers used their index to analyse the vulnerability to coastal flooding of nine cities built on river deltas: Casablanca (Morocco), Calcutta (India), Dhaka (Bangladesh), Buenos Aires (Argentina), Osaka (Japan), Shanghai (China), Manila (Philippines), Marseille (France) and Rotterdam (the Netherlands). The results of the analysis reveal that the highly prosperous megapolis of Shanghai, in China, is more vulnerable than much poorer cities such as Dhaka in Bangladesh.

“Vulnerability is a complex issue,” explains Professor Nigel Wright, who led the team from the University of Leeds. “It is not just about your exposure to flooding, but the effect it actually has on communities and business and how much a major flood disrupts economic activity. Our index looks at how cities are prepared for the worst – for example, do they have flood defences, do they have buildings that are easy to clean up and repair after the flood? It is important to know how quickly a city can recover from a major flood.”...

The Huangpu River in Shanghai, shot by Jakub Hałun, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license

No comments: