Drivers of future flood risk change for residential buildings in Europe
Authors: Steinhausen Max , Schröter Kai , Lüdtke Stefan , Sairam Nivedita , Paprotny Dominik , Mentaschi Lorenzo , Alfieri Lorenzo , Dottori Francesco , Kreibich Heidi 
Published: March 2021

&lt;p&gt;&lt;span&gt;Flood&lt;/span&gt;&lt;span&gt;s&lt;/span&gt; &lt;span&gt;have caused annual economic losses of 1&lt;/span&gt;&lt;span&gt;2.5&lt;/span&gt;&lt;span&gt; billion Euro on average in the past decade in &lt;/span&gt;&lt;span&gt;European Union&lt;/span&gt; &lt;span&gt;m&lt;/span&gt;&lt;span&gt;ember &lt;/span&gt;&lt;span&gt;s&lt;/span&gt;&lt;span&gt;tates (&lt;/span&gt;&lt;span&gt;&lt;em&gt;https://www.eea.europa.eu/data-and-maps/indicators/direct-losses-from-weather-disasters-4/assessment&lt;/em&gt;&lt;/span&gt;&lt;span&gt;). &lt;/span&gt;&lt;span&gt;With global change flood risk is expected to increase significantly, &lt;/span&gt;&lt;span&gt;imposing great challenges for risk management and adaptation. &lt;/span&gt;&lt;span&gt;A better understanding of the major drivers of future flood risk at the continental scale &lt;/span&gt;&lt;span&gt;is required &lt;/span&gt;&lt;span&gt;for &lt;/span&gt;&lt;span&gt;a&lt;/span&gt;&lt;span&gt; forward-looking f&lt;/span&gt;&lt;span&gt;lood risk management &lt;/span&gt;&lt;span&gt;by &lt;/span&gt;&lt;span&gt;legislative and commercial actors&lt;/span&gt;&lt;span&gt;.&lt;/span&gt;&lt;/p&gt;&lt;p&gt;&lt;span&gt;Our &lt;/span&gt;&lt;span&gt;contribution &lt;/span&gt;&lt;span&gt;aim&lt;/span&gt;&lt;span&gt;s&lt;/span&gt; &lt;span&gt;to examine&lt;/span&gt;&lt;span&gt; the change&lt;/span&gt;&lt;span&gt;s and driving forces&lt;/span&gt;&lt;span&gt; in flood risk for residential buildings in Europe under future climate scenarios and socio-economic development. &lt;/span&gt;&lt;span&gt;To observe the &lt;/span&gt;&lt;span&gt;influence of climate change on flood risk our&lt;/span&gt;&lt;span&gt; study &lt;/span&gt;&lt;span&gt;builds on flood hazard data for two climate scenarios under RCP4.5 and RCP8.5 in&lt;/span&gt;&lt;span&gt; three future per&lt;/span&gt;&lt;span&gt;iods centered around the years 2025, 2055 and 2085 (&lt;/span&gt;&lt;span&gt;&lt;em&gt;Mentaschi et al., 2020&lt;/em&gt;&lt;/span&gt;&lt;span&gt;). &lt;/span&gt;&lt;span&gt;Future c&lt;/span&gt;&lt;span&gt;hanges in the value &lt;/span&gt;&lt;span&gt;of&lt;/span&gt;&lt;span&gt; expos&lt;/span&gt;&lt;span&gt;ed &lt;/span&gt;&lt;span&gt;residential buildings are based on population growth, economic growth and changes in the wealth-to-income ratio &lt;/span&gt;&lt;span&gt;(&lt;/span&gt;&lt;span&gt;&lt;em&gt;Paprotny&lt;/em&gt;&lt;/span&gt;&lt;span&gt;&lt;em&gt; et al. 2020&lt;/em&gt;&lt;/span&gt;&lt;span&gt;)&lt;/span&gt;&lt;span&gt;. Three scenarios &lt;/span&gt;&lt;span&gt;describe&lt;/span&gt;&lt;span&gt; a &lt;/span&gt;&lt;span&gt;&amp;#8220;realistic&amp;#8221;,&lt;/span&gt;&lt;span&gt; &amp;#8220;optimistic&amp;#8221;&lt;/span&gt;&lt;span&gt; and &amp;#8220;pessimistic&amp;#8221; view on exposure development. &lt;/span&gt;&lt;span&gt;We &lt;/span&gt;&lt;span&gt;use&lt;/span&gt;&lt;span&gt; the probabilistic multi-variable flood loss model BN-FLEMOps to estimate flood loss (&lt;/span&gt;&lt;span&gt;&lt;em&gt;L&amp;#252;dtke et al. 2019&lt;/em&gt;&lt;/span&gt;&lt;span&gt;). This model &lt;/span&gt;&lt;span&gt;accounts for multiple&lt;/span&gt;&lt;span&gt; hazard &lt;/span&gt;&lt;span&gt;and r&lt;/span&gt;&lt;span&gt;esistance &lt;/span&gt;&lt;span&gt;variables&lt;/span&gt; &lt;span&gt;connected in a Bayesian network &lt;/span&gt;&lt;span&gt;to describe flood vulnerability &lt;/span&gt;&lt;span&gt;and provides information about modeling uncertainties. Further, it allows to quantify the effect of private precaution. &lt;/span&gt;&lt;span&gt;Scenarios for different levels of private precautionary measures and large technical flood protection infrastructure provide insight into the effects of adaptation strategies. &lt;/span&gt;&lt;span&gt;Comparing the flood loss estimations for the future scenarios in 2025, 2055 and 2085 to a baseline for the historic period around the year 1995 reveals the impact of different drivers of future flood risk change for residential buildings in Europe&lt;/span&gt;&lt;/p&gt;