Development of a regionally consistent and fully probabilistic earthquake risk model for Central Asia

• Published in: Natural hazards and earth system sciences Vol. 24; no. 11; pp. 3851 - 3868
• Main Authors: Salgado-Gálvez, Mario A, Ordaz, Mario, Huerta, Benjamín, Garay, Osvaldo, Avelar, Carlos, Fagà , Ettore, Kohrangi, Mohsen, Ceresa, Paola, Triantafyllou, Georgios, Begaliev, Ulugbek T
• Format: Journal Article
• Language: English
• Published: Katlenburg-Lindau Copernicus GmbH 11-11-2024; Copernicus Publications
• Subjects: Disaggregation; Disaster risk; Earthquakes; Economic impact; Environmental risk; Estimates; Floods; GDP; Geological hazards; Gross Domestic Product; Hazard assessment; Infrastructure; Insurance applications; Public buildings; Regional analysis; Risk assessment; Risk levels; Risk management; Seismic activity; Seismic engineering; Seismic hazard; Seismology; Central Asia; Kazakhstan; Kyrgyzstan
• ISSN: 1684-9981; 1561-8633; 1684-9981
• DOI: 10.5194/nhess-24-3851-2024

A fully probabilistic earthquake risk model was developed for five countries in Central Asia, providing updated earthquake loss estimates with a higher level of detail on all components with respect to previous studies in the region. Additionally, a regionally consistent approach that, on the one hand, allows for direct comparisons at different disaggregation levels (e.g., country and oblast) was used. On the other hand, this updated earthquake risk assessment aims to facilitate initiating a policy dialogue regarding national and regional disaster risk financing and insurance applications. This earthquake risk model made use of a regional probabilistic seismic hazard analysis and a comprehensive exposure database on which different types of assets and sectors were included and for which two scenarios (the years 2020 and 2080) were modeled. For each type of asset, a unique vulnerability function was derived and later used for convolution with the hazard data, which allowed for the estimation of the loss exceedance curve, at different disaggregation levels, from where other risk metrics such as the average annual loss (AAL) and specific return period losses were obtained. The regional earthquake AAL for the five countries and for the 2020 exposure scenario has been estimated to be around USD 2 billion, with the Kyrgyz Republic and Tajikistan being the countries with the highest earthquake risk levels in the region. Besides the probabilistic earthquake risk results, as-if scenarios were modeled using a pseudo-deterministic approach to assess the human and economic losses for realistic and representative earthquakes for the main cities within earthquake-prone regions in the five countries of the study area.