Speaker
Description
The sixth special report of the Intergovernmental Panel on Climate Change (IPCC)highlights uncertainty regarding whether the rise in fatalities is due to more landslide events or increased human activity. The Hindu Kush Himalaya exemplifies the convergence of climate change and urbanization impacts on landslide risk. While urban expansion may increase the vulnerability of the Himalayan population to landslides, no empirical studies currently assess these hypotheses across the Himalaya. In this study, we use time-series earth observations and machine learning to estimate landslides and built-up areas across the Himalaya from 1992 to 2020. Our approaches were validated and proved to be more accurate than any publicly available datasets. The high-resolution information at a large scale allows us to address the following questions: (i) What are the rates and topographical patterns of urbanization in the Himalaya? (ii) What are the rates and patterns of landslides, and how do they converge with urbanization? (iii) How much of the increase in landslides and urbanization accounts for increased exposure? and (iv)Where are the hotspots of increasing risks, and what are their underlying drivers? Our results show no linear trend in the total landslide area during the study period. However, the percentage of built-up area exposed to landslides shifted from 9% (46km²) in 1992 to 15% (276 km²) in 2020. This means that the absolute built-up area exposed to landslides increased by 513% over 29 years. Three-fourths of the increase in landslide exposure is due to new development in existing landslide-prone areas, while one-fourth is due to urbanization-caused landslides. Comprehensive information about the locations of frequent landslides is crucial for urban planning and transboundary disaster mitigation.
| Keywords | landslides; urbanization; mountain development; sustainable development; risk assessment |
|---|---|
| Best Congress Paper Award | Yes |
