Flood risks/Policy issues

Component is implemented in:

GLOFRIS model (version GLOFRIS 3.0) Components: Flood risks

Related IMAGE components

Drivers Human development Land cover and land use

Models/Databases

DIVA model PCR-GLOBWB model

Key publications

Ward et al., 2013 Winsemius et al., 2012

Flowchart Flood risks. See also the Input/Output Table on the introduction page.

Baseline developments

GLOFRIS can be used to assess a wide range of scenarios based on data on land cover and climate change. The module , for instance, has been used to analyse the impact of floods on Bangladesh published in Winsemius et al., 2012. Calculations showed that population and economic growth are more likely to have greater impact on future flood risks than the impacts of climate change. Thus, the focus would need to be on how the changes in socio-economic conditions can be combined with flood risk reduction.

The study compares the current situation with the impacts of changes in climate and socio-economic conditions. The left panel in the figure below shows the pattern of a flood occurring once every 30 years according to GLOFRIS, scaled down to 1x1 km² over Bangladesh, under current climate conditions. The right-hand panels in the figure below show the resulting expected values of damage under current climate and socio-economic conditions, based on the two methods described in Winsemius et al., 2012. Flood risks have been computed using the two methods for the reference situation and for two climate data sets.

Inundation depth of 30-year flood scaled down to Bangladesh (left); The estimated annual damage due to floods (not only due to a 30-year event) is more concentrated when applying the land-use method compared to the population method.

Policy interventions

To date, the model has not been used extensively for specific policy interventions. Measures taken elsewhere in the IMAGE framework to prevent climate change could also reduce flood risks.

Future expected annual damage due to flooding depends on future climate change, but much even more on future GDP and population distribution.