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

Abstract. A fully probabilistic earthquake risk model was developed for five countries in Central Asia, providing updated earthquake loss estimates with a higher level of details on all components with respect to previous studies in the region, besides having used a regionally consistent approach that on the one hand, allows direct comparisons at different disaggregation levels (e.g., Country and Oblast), and on the other hand, is aimed 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, as well as a comprehensive exposure database on which different types of assets and sectors were included, and for which two scenarios (years 2020 and 2080) were modelled. For each type of asset, a unique vulnerability function was derived and later used for the convolution with the hazard data that allowed estimating 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 2020 exposure scenario has been estimated in around $2 Bn, being Kyrgyzstan and Tajikistan the countries with the highest earthquake risk levels in the region. Besides the probabilistic earthquake risk results, as-if scenarios were modelled 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 within the study area.