The challenge of unprecedented floods and droughts in risk management

Risk management has reduced vulnerability to floods and droughts globally, yet their impacts are still increasing. Using a global dataset of 45 pairs of flood and drought events within the same area, the study shows that while risk management generally reduces impacts, it struggles with unprecedented events whose magnitude exceeds prior experience. When the second event is much more hazardous than the first, impacts are almost always higher, often surpassing the design limits of levees and reservoirs. Two success stories demonstrate that improved governance and high investment in integrated management can reduce impacts despite increased hazard. The findings are concerning given projections of more extreme hydrological events due to climate change.

Heidi Kreibich, Anne F. Van Loon, Kai Schröter, Philip J. Ward, Maurizio Mazzoleni, Nivedita Sairam, Guta Wakbulcho Abeshu, Svetlana Agafonova, Amir AghaKouchak, Hafzullah Aksoy, Camila Alvarez-Garreton, Blanca Aznar, Laila Balkhi, Marlies H. Barendrecht, Sylvain Biancamaria, Liduin Bos-Burgering, Chris Bradley, Yus Budiyonos, Wouter Buytaerts, Lucinda Capewell, Hayley Carlson, Yonca Cavus, Anaïs Couasnon, Gemma Coxon, Ioannis Daliakopoulos, Marleen C. de Ruiter, Claire Delus, Mathilde Erfurt, Giuseppe Esposito, Didier François, Frédéric Frappart, Jim Freer, Natalia Frolova, Animesh K. Gain, Manolis Grillakis, Jordi Oriol Grima, Diego A. Guzmán, Laurie S. Huning, Monica Ionita, Maxim Kharlamov, Dao Nguyen Khoi, Natalie Kieboom, Maria Kireeva, Aristeidis Koutroulis, Waldo Lavado-Casimiro, Hong-Yi Li, María Carmen LLasat, David Macdonald, Johanna Mård, Hannah Mathew-Richards, Andrew McKenzie, Alfonso Mejias, Eduardo Mario Mendiondo, Marjolein Mens, Shifteh Mobini, Guilherme Samprogna Mohor, Viorica Nagavciuc, Thanh Ngo-Duc, Thi Thao Nguyen Huynh, Pham Thi Thao Nhi, Olga Petrucci, Hong Quan Nguyen, Pere Quintana-Seguís, Saman Razavi, Elena Ridolfis, Jannik Riegel, Md Shibly Sadik, Elisa Savelli, Alexey Sazonov, Sanjib Sharma, Johanna Sörensen, Felipe Augusto Arguello Souza, Kerstin Stahl, Max Steinhausen, Michael Stoelzle, Wiwiana Szalińska, Qiuhong Tang, Fuqiang Tian, Tamara Tokarczyk, Carolina Tovar, Thi Van Thu Tran, Marjolein H. J. Van Huijgevoorts, Yueling Wang, Doris E. Wendt, Sergiy Vorogushyn, Thorsten Wagener, Michelle T. H. van Vliet, Elliot Wickham, Long Yang, Mauricio Zambrano-Bigiarini, Günter Blöschl, Giuliano Di Baldassarre