Satellite-based data driven quantification of pluvial floods over Europe under future climatic and socioeconomic changes.

Flooding is one of the major threats jeopardizing lives and properties of the people, and its risk is expected to increase remarkably under changing climatic and socioeconomic conditions. Yet, future flood risk has not been well studied due primarily to a limited availability of detailed and consistent data on future vulnerability components and the computationally expensive continental flood modeling. Here we perform a top-down data driven flood risk assessment for 20-, 30-, 50- and 100-year return periods over Europe at the continental, regional and national levels for the late 21st century. To account for the impact of changes in both climatic and socioeconomic conditions on floods, the Shared Socioeconomic Pathways (SSPs) are merged with Representative Concentration Pathways (RCPs), integrating hazard and several social, economic and agricultural exposure-vulnerability proxy indicators. Our results show a ubiquitous drastic increase up to 87% in future flood risks of different return periods over Europe, with eastern and southern regions experiencing the highest risk increase. A fossil-fuel based development in the future would lead to 14-15% higher flood risk compared to a sustainable development, which goes up to 23% in north Europe. The amplified future flood risk is predominantly driven by climate change, although with a large uncertainty, rather than socioeconomic drivers.