Implications of global warming and urban land use change on flooding in Europe

This paper presents an integrated methodology to assess the implications of climate change and urban land use changes on future flood damage in Europe. To determine changes in flood hazard due to global warming, high resolution regional climate simulations from the HIRHAM model were used to drive the hydrological model LISFLOOD. Calculated flood inundation extents and depths were transformed into direct monetary damage using flood depth-damage functions and land use information. For each country Expected Annual Damages (EAD) were calculated from the damage-probability functions. To account for flood protection the damage-probability functions were truncated at design return periods based on the country GDP. Results indicate that, under the A2 scenario, most countries in Europe will see an increase in EAD in the coming century. For EU27 as a whole, current EAD of 6.5 billion is projected to reach 18 billion (in constant prices of 2006) by the end of this century under the A2 scenario. For the region of Madrid, future developments in urban land use were simulated with the cellular automata (CA)-based model MOLAND. Damage calculations based on the future land use patterns for this region show that the effect of increased exposure due to urban expansion far outweighs the effect of climate change.