Preface: Advances in flood risk assessment and management

Abstract

Abstract. Floods are among Earth's most common and most destructive natural hazards, affecting human lives and properties directly and indirectly around the world. The frequency and magnitude of extreme flooding have been increasing in many parts of the world in recent decades (see, e.g. Berghuijs et al., 2017; Blöschl et al., 2019a; Marijnissen et al., 2019), hampering human well-being and economic growth in both developed and developing countries. Flood risk management carries out the flood risk assessment and uses appropriate resources (human, finance, science and technology, and nature) to control the flood risk (Han, 2011), which is an urgent challenge for the scientific and engineering communities to address. In a similar way to “Twenty-three unsolved problems in hydrology” (Blöschl et al., 2019b), despite decades of research in this field, there are still many unsolved problems in floods as well. This special issue “Flood Risk Assessment and Management” is an outcome of the session “Flood Risk Assessment and Management” in the Naturals Hazards Division at the European Geosciences Union (EGU) General Assembly held in Vienna, Austria. The session series has been organized annually at EGU since 2018. This special issue presents a wide range of in-depth research studies based on flood modelling (including hydrological modelling and hydrodynamic modelling), hazard mapping, flood damage and risk assessment as well as studies that focus on flood relief prioritization, mitigation strategies and flood policies. Extraordinary floods and debris flows are also included due to dam and dike breaks and extreme storms over gullies in mountain areas. The nine articles in this special issue are broadly introduced in the following three categories.

Identification of dominant hydrological mechanisms using Bayesian inference, multiple statistical hypothesis testing and flexible models

“…Scientifically, models help to understand and communicate catchments functioning and internal process dynamics (e.g., Wheather et al, 1993;Beven, 2010;Gupta et al, 2012). Operationally, hydrological models are used to manage water resources (including designing mitigation measures in anticipation of projected changes in the environment, e.g., due to changes in climate and/or land use), to implement flood early warning systems, and to help design and manage hydraulic structures, among others (e.g., Wagener et al, 2010;Montanari et al, 2013;Srinivasan et al, 2017;Prieto et al, 2020).…”

Identification of Dominant Hydrological Mechanisms Using Bayesian Inference, Multiple Statistical Hypothesis Testing, and Flexible Models

“…Scientifically, models help to understand and communicate catchments functioning and internal process dynamics (e.g., Wheather et al., 1993; Beven, 2010; Gupta et al., 2012). Operationally, hydrological models are used to manage water resources (including designing mitigation measures in anticipation of projected changes in the environment, e.g., due to changes in climate and/or land use), to implement flood early warning systems, and to help design and manage hydraulic structures, among others (e.g., Wagener et al., 2010; Montanari et al., 2013; Srinivasan et al., 2017; Prieto et al., 2020).…”

How to mitigate flood events similar to the 1979 catastrophic floods in the lower Tagus

“…In this sense, hydrodynamic numerical models are a key tool in flood risk management by providing information on critical flood indicators (Shah et al, 2022;Zhang et al, 2022). This will contribute to addressing the flood mitigation challenges that the scientific community will face in the coming decades (IPCC, 2012(IPCC, , 2021Prieto et al, 2020). These are related to the increasing temperatures due to the significant rates of global warming that have contributed to and will continue to contribute to the recent and future increase in extreme precipitation and floods in some parts of the world (Dankers and Feyen, 2008;Petrow and Merz, 2009;Alfieri et al, 2015Alfieri et al, , 2017Diakakis, 2016;Arnell and Gosling, 2016;Modarres et al, 2016;Jongman, 2018;IPCC, 2021), including vast areas of the Iberian Peninsula (Lorenzo and Alvarez, 2020).…”