This special issue aims to (1) provide a high-quality collection of papers showcasing methodological advances in compound- and multi-risk analysis and management, (2) consolidate and foster learning across the compound-risk and (multi-hazard) multi-risk research fields, and (3) identify future research avenues.

Recent years have demonstrated the immense challenges faced by society as a result of the increasing complexity of disaster risk and due to climate change. Societies impacted by multiple natural hazards (either in sequence or at the same time) face different challenges than when impacted by a single hazard that occurs in isolation (AghaKouchak et al., 2020; Hillier and Dixon, 2020; Raymond et al., 2020a). The impacts of compound- and multi-hazard disasters are complex and may be driven by the consecutive nature of the (drivers of) hazards themselves (Hillier et al., 2020; Mora et al., 2018; Ridder et al., 2020; Zscheischler et al., 2018), the spatiotemporal dynamics in exposure and vulnerability caused by earlier events (de Ruiter et al., 2020; de Ruiter and Van Loon, 2022; Reichstein et al., 2021), or the influences of risk management on the dynamics of risk (Simpson et al., 2022). This makes managing compound- and multi-risk disasters especially complex, and several studies have noted that their management may require more comprehensive approaches than single-hazard disasters (Simpson et al., 2023; De Ruiter et al., 2021; Schippers, 2020).

In recent years, international agreements such as the Paris Agreement (2015) and the UN’s Sendai Framework for Disaster Risk Reduction (SFDRR) (UNDRR, 2015) have called upon the disaster risk science community to move away from siloed hazard thinking (i.e. assessing the risk from hazards one by one) and toward improving our understanding of these spatiotemporal complexities of disaster risk. Similarly, the latest series of Intergovernmental Panel on Climate Change (IPCC) reports recognizes the importance of accounting for multiple and complex risks. In a recent survey of members of the natural hazard research community, respondents noted that multi-hazards and resulting risks remain one of the core scientific challenges to be tackled (Sakic Trogrlic et al., 2022).

Subsequently, the past years have seen a rise in compound- and multi-risk (multi-hazard) studies that try to capture some of these complexities through advanced statistical methods (e.g. Zscheischler, 2017; Bevacqua et al., 2022; Couasnon et al., 2020), physically based models (Eilander et al., 2023; Couasnon et al., 2022), and multi-risk system analysis (e.g. Simpson et al., 2022; De Angeli et al., 2022; Van Westen and Greiving, 2017; Gill and Malamud, 2017; Ward et al., 2022). As a result, the compound- and multi-risk communities have developed largely in parallel with each other, and only in recent months have significant efforts been made to bring these two communities together, for example, as demonstrated by the American Geophysical Union (AGU) 2022 session focusing specifically on breaking silos between the two communities.

However, there is some interesting methodological and conceptual overlap between these communities and thus strong potential for catalyzing learning and innovation for (advancing) risk studies. The call from the international community has resulted in a proliferation of innovative methodological approaches across different disciplines, offering a vast array of possible options for multi- and systemic-risk reduction in practice. The importance of this topic is also apparent in recently funded research and networking projects including Damocles, The HuT, MIRACA, MYRIAD-EU, MEDiate, PARATUS, RECEIPT, CLIMAAX, Tomorrow’s Cities, Risk KAN, and NOAA’s Climate Adaptation Partnerships (formerly RISA), among others.

As early career researchers from both fields, we have contributed to shaping these two communities, and we perceive the need to bring them together to assess solutions for the future. However, despite these advances, there is still no single collection of high-quality scientific research papers focusing on methodological innovations for the analysis and management of both compound and multiple risks.

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