Brussels – Floods with aggravating factors, which occur when heavy rainfall combines with human and environmental factors that amplify their destructive impact, have almost tripled in 30 years, and, alongside them, the average economic losses resulting from them are almost three times higher than the losses resulting from floods alone. For this reason, the European Union must adopt “multi-risk approaches” that allow for “the integration of information on combined risks, and not just on the severity of individual floods” in order to “significantly improve the ability to anticipate the most damaging events.” This is established by a new international study conducted by scientists from the Joint Research Centre, the European Commission’s science and knowledge service, in collaboration with the Potsdam Institute for Climate Impact Research, Vrije Universiteit Amsterdam and the University of Leuven.
For the study, the researchers used a database of historical flood impacts containing meteorological and hydrological records, covering 1,349 flood events between 1981 and 2020. They examined five case studies of combined flood events: floods preceded by wet conditions, transitions from drought to flood, heatwaves–flood sequences, cold spells–floods and windstorms–floods. In this way, the authors found that regions where floods occur alongside other hazards, such as droughts, heatwaves or windstorms before or after flooding, consistently suffer greater average losses. In already fragile regions, the effect is even stronger, suggesting that physical and social risks reinforce one another.
The data reveals a worrying trend: floods are increasingly occurring alongside two or more other hazards. Between the 1980s and the 2010s, these compound events increased by 186 per cent—compared with just 16 per cent for floods occurring on their own. The issue is real: researchers have found that over 70 per cent of flood events in Europe are compound events, combining multiple hazards that contribute to social or environmental risk. They involve at least one aggravating risk. On average, losses due to floods combined with other risks were 2.8 times higher than those resulting from floods alone over the 30-year study period. Every event that falls within the top 1 per cent of economic losses falls into one of these types of compound events.
Examples include the floods in Emilia-Romagna in May 2023, which struck following a prolonged drought, or the storms that bring extreme winds and flooding. The problem is that most risk models, insurance frameworks, and early warning systems still treat floods as stand-alone events.
For this reason, the call is to “adopt multi-risk approaches” within the European institutions: in this way, the EU will be able to “anticipate disaster resilience” by assessing regional risks and civil protection planning; integrating the complexity of compound risks would help to identify the regions most at risk, enabling more targeted preparedness and response.
The debate on the response to—and prevention of—natural disasters in the EU is currently underway in Brussels. Currently, in the event of an emergency, the EU can first activate its Civil Protection Mechanism, which organises and coordinates an emergency response among participating states, and the Solidarity Fund, which combines two mechanisms to simplify the aid process, enabling both faster and more flexible emergency efforts and long-term recovery efforts. Finally, the Union can always draw on funds from the EU Cohesion Policy to rebuild infrastructure, repair damaged public services, and improve disaster preparedness for future emergencies. But this is not enough; more needs to be done. In February, the European Commissioner for Crisis Response, Hadja Lahbib, had reported the European Commission’s intention to create an integrated framework for climate resilience, accompanied by a support programme to “build resilience from the design stage: this will include a streamlined legislative proposal and support measures.”
English version by the Translation Service of Withub
