A capital city at risk and no transformation of urban development? Forensic disaster risk assessment in the case of Ulaanbaatar in Mongolia

Abstract Ulaanbaatar, the capital of Mongolia, has experienced major floods in 1966 and, more recently, in 2023. Given that half of Mongolia’s population is concentrated in cities, it is important to understand the persistent flood risk and the differential vulnerability of the population and infrastructure. A forensic disaster risk assessment is conducted using open-source satellite and geoinformation data. Combined with field visits for ground truthing, land use classification is applied, showing that large informal settlements are mainly exposed to gravitational hazards. In contrast, other urban residential, commercial, and industrial areas are mainly exposed to flood risk in the large floodplain south of the city. Satellite images from 1967 to today show that urban expansion has increased further after flood events and has not stopped to this day. Political regime changes and previous floods did not stop urban development, leading to a ‘non-transformation’. ‘Building forward better’ for planners requires utilising such information to foster transformations in disaster risk reduction.