National‐Scale Rainfall‐Triggered Landslide Susceptibility and Exposure in Nepal

Type of content
Journal Article
Thesis discipline
Degree name
Publisher
American Geophysical Union (AGU)
Journal Title
Journal ISSN
Volume Title
Language
en
Date
2024
Authors
Kincey ME, M. E.
Rosser , N. J.
Swirad , Z. M.
Robinson, Tom
Shrestha , R.
Pujara , D. S.
Basyal , G. K.
Densmore , A. L.
Arrell , K.
Oven , K. J.
Abstract

jats:titleAbstract</jats:title>jats:pNepal is one of the most landslide‐prone countries in the world, with year‐on‐year impacts resulting in loss of life and imposing a chronic impediment to sustainable livelihoods. Living with landslides is a daily reality for an increasing number of people, so establishing the nature of landslide hazard and risk is essential. Here we develop a model of landslide susceptibility for Nepal and use this to generate a nationwide geographical profile of exposure to rainfall‐triggered landslides. We model landslide susceptibility using a fuzzy overlay approach based on freely‐available topographic data, trained on an inventory of mapped landslides, and combine this with high resolution population and building data to describe the spatial distribution of exposure to landslides. We find that whilst landslide susceptibility is highest in the High Himalaya, exposure is highest within the Middle Hills, but this is highly spatially variable and skewed to on average relatively low values. Around 4 × 10jats:sup6</jats:sup> Nepalis (∼15% of the population) live in areas considered to be at moderate or higher degree of exposure to landsliding (>0.25 of the maximum), and critically this number is highly sensitive to even small variations in landslide susceptibility. Our results show a complex relationship between landslides and buildings, that implies wider complexity in the association between physical exposure to landslides and poverty. This analysis for the first time brings into focus the geography of the landslide exposure and risk case load in Nepal, and demonstrates limitations of assessing future risk based on limited records of previous events.</jats:p>

Description
Citation
Kincey ME, Rosser NJ, Swirad ZM, Robinson TR, Shrestha R, Pujara DS, Basyal GK, Densmore AL, Arrell K, Oven KJ, Dunant A (2024). National‐Scale Rainfall‐Triggered Landslide Susceptibility and Exposure in Nepal. Earth's Future. 12(2).
Keywords
Ngā upoko tukutuku/Māori subject headings
ANZSRC fields of research
37 - Earth sciences::3709 - Physical geography and environmental geoscience::370903 - Natural hazards
41 - Environmental sciences::4106 - Soil sciences::410605 - Soil physics
Rights
All rights reserved unless otherwise stated