Lorenzo Alfieri at the EC’s Joint Research Centre has published two papers on the frequency and cost of river floods in Europe.
According to a JRC study published on 24 September, projections under a “high-end“ climate scenario show that river floods in Europe could directly affect more than half a million people a year by 2050 and nearly one million by 2080, as compared to about 200 thousand today. Related annual damages could climb from the current 5.3 billion EUR to up to 40 billion EUR in 2050 and reach 100 billion EUR by 2080, due to the combined effect of climatic change and socio-economic growth.
The study assesses the future flood risk in Europe under high levels of global warming, combining projections of extreme streamflow based on EURO-CORDEX RCP8.5 climate scenarios with recent advances in European flood hazard mapping. Under these high-end climate scenarios, estimates of population affected and direct flood damages indicate that in 2080 the socio-economic impact of river floods in Europe could more than triple, i.e. rise by an average 220% due to climate change alone.
An earlier JRC study published in May 2015, showed a substantial increase in the future flood hazard under high end scenarios, due to a pronounced increase in the frequency of extreme river flooding as opposed to relatively smaller changes in the flood magnitude. In Europe, the flood peaks that currently strike less than once a century are projected to double in frequency within the next few decades. Such flood peaks are mostly above the average protection level of European rivers and may have devastating impacts on our society if adaptation measures are not implemented in due time. The climate projections of the study also indicate a 30% reduction in the mean annual precipitation in southern European countries, particularly in the Iberian Peninsula, Greece and southern Italy. However extreme daily rainfall accumulations are likely to increase across Europe, increasing the need for flood mitigation plans and efficient management of water resources.
EURO-CORDEX is a new generation of downscaled climate projections that is used for climate change impact studies in Europe. The climate RCP8.5 scenario of the Intergovernmental Panel on Climate Change (IPCC) assumes the highest levels of greenhouse gas emissions, and foresees a global temperature rise exceeding 4⁰C before the end of the century. RCP8.5 assumes high population, slow income growth, modest technological innovation and energy intensity improvements leading to high energy demand, without change in climate policies.