Kamal Ghorui
Bhubaneswar: Landslides are triggered by the combined impact of climate change and rapid development — not just extreme rainfall and unstable terrain, but human activities as well — a new study by Balasore-based Fakir Mohan University teachers, along with international collaborators, has found. It has recommended reforestation, regulated construction and targeted monitoring in high-risk zones.The researchers — who have mapped the landslide-prone zones across the Western Ghats by using advanced machine-learning techniques — have said the findings are part of a larger emerging pattern across India’s mountainous regions, from the Western Ghats to Himalayas, where short-duration and high-intensity rainfall — often described as ‘atmospheric floods’ or cloudburst-like downpours — are becoming more frequent and destructive.Importantly, the study, published in journal ‘Earth Surface Processes and Landforms’ on May 6, found that nearly 72% of landslides occurred near roads or developed areas, underlining the impact of infrastructure expansion, hill cutting and slope modification.According to the study by Manoranjan Mishra and his colleagues, along with international collaborators, landslides in the Western Ghats are being exacerbated by “intense rainfall — aggravated by climate change — and inadequate environmental and urban planning”, making the region increasingly vulnerable.The Western Ghats typically receive 3,000-4,000mm annual rainfall during southwest monsoon. However, the rainfall is no longer evenly distributed. Instead, intense bursts over short periods are saturating soil rapidly, weakening slopes and triggering landslides, debris flows and flash floods. Events such as 2018 Kerala floods and Kodagu landslides are examples of this growing climate threat.Using geospatial data and 22 environmental factors, the researchers applied four machine-learning models, including random forest, to identify areas susceptible to landslides.“District-level factors such as deforestation, slope modification and heavy rainfall were significant contributors,” said Mishra, stressing that land-use changes are intensifying risks in the region.The analysis classified the Western Ghats into zones ranging from very low to very high susceptibility, with large stretches falling under moderate to high-risk categories. The most vulnerable areas were concentrated in parts of Maharashtra, Karnataka, Kerala and Tamil Nadu, including districts such as Wayanad, Idukki, Kodagu and Raigad.The study also identified key drivers of landslides, including rainfall intensity, elevation, geological structures, proximity to faults, land-use changes and population pressure.Mishra said that landslides are now emerging as a major threat to infrastructure like highways, railways, tourism centres and settlements in hilly regions, with slope failures often cutting off villages, damaging utilities and disrupting economic activity.The researchers said the findings could aid disaster preparedness and policy planning. “The susceptibility maps can support regional planning, early warning systems and disaster mitigation strategies,” the study said.They stressed the need for a multipronged approach, including real-time rainfall monitoring, strict controls on construction in vulnerable areas, improved road engineering, ecological restoration and community awareness.The researchers warned that without urgent action, landslide disasters are likely to intensify as climate change increases extreme rainfall events. Protecting mountain ecosystems, they said, is now critical not only for environmental conservation but also for safeguarding lives, infrastructure and long-term climate resilience.
