Uncertainties in catastrophe modelling: Focus on seismic hazard uncertainty based on ESHM updates

Abstract Catastrophe models serve as valuable tools for evaluating and managing the impacts of natural disasters, yet their accuracy is susceptible to inherent uncertainties. This article explores the implications of uncertainty within catastrophe models, with a specific focus on the hazard component. The introductory section, presents an analytical framework for developing the three main components of an earthquake catastrophe model - hazard, vulnerability, and exposure – and discussed the associated uncertainties. The subsequent section underscores the crucial role of sufficient data for accurate risk assessment, highlighting the sensitivity of the estimates to hazard modeling assumptions and structural system properties. It discusses the role of extrapolation techniques in refining hazard curves, together with limitations and challenges. The final section presents a comparative analysis of two versions of the European Seismic Hazard Model (ESHM), ESHM13 vs ESM20, examining the effects of hazard variation on risk outcomes across different locations. Lastly, the paper suggests a simplified method to model future updates of the hazard model, assessing the potential implications on RM estimates for different structural systems.