# Presentation: 262529

## Assessing Natural Hazard Risk in Urban Areas 

- Henrike Brecht
- Louisiana State University

- Emergency Management Higher Education Conference, June 7, 2007

## Why a Risk Index?

- Identifying Risk:
- Key element in disaster reduction
- Enables informed policy making
- Index:
- Summarizes a body of knowledge
- Easy to understand
- Facilitates comparisons

- Emergency Management Higher Education Conference, June 7, 2007

## Urban Risk Index

- Follow-up of World Bank Disaster Hotspots
- Multi-hazard index
- All cities worldwide with more than 100,000 inhabitants
- Outcome: Relative risks of
- mortality
- economic losses

- Emergency Management Higher Education Conference, June 7, 2007

## What is Risk?

_**Risk = Hazard x Exposed Elements x Vulnerability**_
*Hazard*
- Derived from historic hazard data
*Exposed Elements*
- City Population
- City GDP
*Vulnerability*
- Population vulnerability: derived from historic death tolls
- Economic vulnerability: derived from historic economic losses

- Emergency Management Higher Education Conference, June 7, 2007

## Data Inputs: Hazards

- Five major hazards
- Vector data was gridded, raster data was resampled at 1 km resolution.

- Emergency Management Higher Education Conference, June 7, 2007

## Data Inputs: Cyclones

- Emergency Management Higher Education Conference, June 7, 2007

## Data Inputs: Landslides

- Emergency Management Higher Education Conference, June 7, 2007

## Data Inputs: Floods

- Emergency Management Higher Education Conference, June 7, 2007

## Data Inputs: Earthquakes

- Emergency Management Higher Education Conference, June 7, 2007

## Data Inputs: Exposed Elements

- City population numbers (Henderson)
- City GDP (World Bank)
- City footprints: GRUMP (Global Rural-Urban Mapping Project) by CIESIN

- Emergency Management Higher Education Conference, June 7, 2007

## Data Inputs: Exposed Elements

- Emergency Management Higher Education Conference, June 7, 2007

## Data Inputs: Vulnerability

- Not based on social vulnerability indicators
- Damage rates by hazard
- EM-DAT (Emergency Disaster Database)
- Population vulnerability:
- historic death tolls per hazard
- Economic vulnerability:
- economic loss rate per hazard

- Emergency Management Higher Education Conference, June 7, 2007

## Outcomes

- For each city
- Mortality risk index
- Economic risk index
- Relative risk levels

- Emergency Management Higher Education Conference, June 7, 2007

## Earthquake Mortality Risk

- Emergency Management Higher Education Conference, June 7, 2007

## Conclusion

- Index is a comprehensive summary and enables comparisons
- Guides policy making and resource  allocation
- Index creation is impeded due to lack of accurate data
- Macro analysis which does not replace careful risk assessments for cities

- Emergency Management Higher Education Conference, June 7, 2007

## A Glance Ahead

- Individual city assessment
- Improve global flood and landslide hazard data
- Improve global loss data

- Emergency Management Higher Education Conference, June 7, 2007

## 
Thank you.

Henrike Brecht
henrike@hurricane.lsu.edu

- Thank you.
- Henrike Brecht
- henrike@hurricane.lsu.edu

- Emergency Management Higher Education Conference, June 7, 2007