National Institute of Oceanography and Applied Geophysics (OGS) · Trieste, Italy
NATURALandslide risk in mountain regions · OGS

Italian Science Fund · FIS 3 Starting Grant · 2026–2031

Hosted at OGS, Trieste · Principal Investigator Sansar Raj Meena

Who is at risk when mountains and people change together?

NATURA studies how natural processes and human activity together shape landslide risk in mountain regions. It measures where and how often slopes fail, who and what is exposed, and what makes communities vulnerable, in the Himalaya of India and Nepal, the Western Ghats and the Northern Apennines, with further study areas in Africa and South America.

Risk=Hazard×Exposure×Vulnerability

Photo: Perarolo di Cadore, Belluno Dolomites. Drone survey, February 2025.

Landslide inventoriesSusceptibilityHazardExposureVulnerabilityRisk

The project in numbers

5 yearsApril 2026 to March 2031
€1.25 MStarting Grant, Italian Science Fund (FIS 3)
4continents: study areas in Asia, Europe, Africa and South America
3objectives: hazard and human change, vulnerability, future risk

The project

Three objectives

Roads, settlements and land-cover change alter where slopes fail, and people in turn move into or away from landslide-prone ground. Most risk assessments treat these separately. NATURA measures them together.

1

Hazard and human change

Quantify how landslide hazard interacts with human-driven change: roads, settlements and deforestation.

2

Who is vulnerable

Characterise the socio-economic factors that make people exposed and vulnerable to landslides.

3

Future risk

Project landslide risk under climate and socio-economic scenarios, for planning and adaptation.

Research

Three strands, one risk picture

Each strand supplies one part of the risk equation, and each is checked against the other two. Mapping is done on slope units, the natural hillslope units of the terrain.

Drone photo of a landslide scarp above a road
01 / 03

Landslide hazard

Multi-temporal landslide inventories from a decade of satellite imagery. From them: susceptibility, how often slopes fail, how large the failures are, and how road construction changes landslide occurrence.

Inventories · susceptibility · frequency · magnitude

Led by Ankit Singh

Drone photo of a valley town and its river from above
02 / 03

Exposure and vulnerability

How built-up area and roads have spread across landslide-prone slopes through time, and which socio-economic conditions explain who suffers losses.

Elements at risk · census data · vulnerability index

Athif Sayyaf's doctoral research

Drone photo of a road crossing debris-flow deposits
03 / 03

Field, geology and InSAR

Drone LiDAR and field campaigns, lithological and structural controls on slope failure, and satellite radar to detect slow-moving landslides. The field data validate the maps.

UAV LiDAR · structural geology · PSInSAR

Led by Saurabh Singh

Study regions

Four continents, one method

The same workflow is applied in very different settings, from monsoon-driven Himalayan valleys to fast-growing cities on steep tropical slopes, to learn what transfers between them and what does not.

Core study regions Field site Further study areas

Indian Himalaya

Himachal Pradesh and Uttarakhand

Steep, tectonically active terrain with intense monsoon rainfall and fast road and settlement growth.

Trigger
Monsoon rainfall
Record
Monthly satellite imagery, 2016–2026
Pilot
Mandi and Kullu districts

Italy

Northern Apennines

The May 2023 Emilia-Romagna rainfall event triggered tens of thousands of landslides on long-settled hillslopes.

Trigger
Extreme rainfall, May 2023
Record
LiDAR before and after; aerial imagery from 1976
Fieldwork
Drone LiDAR campaigns

North-East India

Sikkim, Mizoram and Manipur

The wettest part of the Himalayan arc, with fast-growing hill towns and new road and rail corridors.

Darjeeling–Sikkim
8,373 landslides on 4,830 slope units, used to test model transfer (Singh et al., 2026)
Mizoram
Aizawl: a hill city on steep ridges
Manipur
Noney district: the 2022 Tupul landslide on a railway construction site

Nepal

Rasuwa, Bhote Koshi–Trishuli valley

A high-mountain valley where an ice–rock avalanche on 26 August 2026 sent a debris flow downstream.

Focus
Cascading hazards and damage to buildings and roads
Data
NISAR and Sentinel-1 radar, very-high-resolution imagery
Work so far
Meena, 2026 (preprint)

Western Ghats, India

Nilgiris and Kerala

Steep, deeply weathered slopes where monsoon rainfall triggers landslides on cut slopes, plantations and settled hillsides.

Tamil Nadu
Nilgiris, the Mettupalayam–Coonoor–Ooty corridor: LiDAR surveys and seismic (MASW) profiling
Kerala
Wayanad and Idukki: areas of the 2018 and 2024 monsoon landslides
Earlier work
Meena et al., 2021

Africa

Western branch of the East African Rift

Densely populated tropical highlands where land-use change, roads and growing towns meet landslide-prone slopes.

Rwanda
North-west Rwanda and Musanze: land-use change and landslide frequency
DR Congo
Kalehe, Kivu Rift: landslides and flash floods under land transformation
Uganda
Kigezi highlands: landslides along roads
Rift-wide
Slow-moving landslides from satellite radar

South America

Andes and Serra do Mar

Cities and towns built on steep slopes, where intense rainfall strikes hillside neighbourhoods.

Colombia
Medellín, Aburrá Valley: dense neighbourhoods high on the valley sides
Brazil
Petrópolis and the Serra do Mar, Rio de Janeiro state: rainfall-triggered landslides in hillside neighbourhoods
Brazil
São Sebastião, São Paulo coast: the February 2023 rainfall event

Roadmap

Five years, three milestones

The milestones overlap: validation in the field starts while the models are still being built, and the scenarios build on both.

2026 – 2029 now

Risk modelling

Landslide inventories, hazard models, exposure and vulnerability for the study regions.

2026 – 2029

Validation through case studies

Field and drone campaigns, stakeholder interviews, and historical aerial and satellite imagery.

2029 – 2031

Scenarios and policy

Risk projections under climate and socio-economic scenarios, and decision-support tools for disaster-risk agencies.

Research programme to 2028

  1. A validated multi-temporal landslide inventory for Himachal Pradesh and UttarakhandHazard
  2. Drone LiDAR and field characterisation of the May 2023 landslides in the Northern ApenninesField and geology
  3. Slope-unit landslide susceptibility, harmonised across regions and tested for transferHazard
  4. How built-up area has spread across landslide-prone slopesExposure
  5. Slow-moving landslides from satellite radar and their structural controlField and geology
  6. Landslide occurrence before and after road constructionHazard and human change
  7. Physically based stability of road-cut slopesHazard and human change
  8. A socio-economic vulnerability index tested against observed lossesVulnerability
  9. Landslide hazard: frequency, magnitude and rainfall thresholdsHazard
  10. Field validation and geological controls on landslide hazard in the HimalayaField and geology

Team

People

NATURA is based in the Geophysics Department of OGS, at Borgo Grotta Gigante near Trieste. The doctoral research is carried out with the University of Padova.

Sansar Raj Meena

Principal Investigator

AI and Earth observation for geohazards. Researcher at OGS.

Ankit Singh

Postdoctoral researcher

Landslide inventories, susceptibility and hazard. PhD, IIT Mandi.

Athif Sayyaf

PhD student, University of Padova

Exposure and socio-economic vulnerability to landslide hazard.

Saurabh Singh

Researcher

Fieldwork, structural geology and InSAR. PhD, Banaras Hindu University.

OGS – National Institute of Oceanography and Applied Geophysics University of Padova, Department of Geosciences

Outputs

Publications, preprints and data

Papers are published open access, with the data needed to check their results. Inventories, maps and code are released as each study is completed.

  1. Integrating geomorphology-based terrain segmentation with machine learning for landslide susceptibility assessment in the Darjeeling Sikkim Himalaya, India. Singh, S., Raju, A., Rosi, A., Singh, R. P., Kumar, S., Floris, M., Meena, S. R. Geosciences, 2026. doi:10.3390/geosciences16100426

Preprints, not yet peer reviewed

  1. Mapping landslide change and volume with repeat airborne LiDAR after the May 2023 Emilia-Romagna event: slope-dependent detection limits and lowered areas. Meena, S. R. EarthArXiv preprint, 2026. doi:10.31223/X58R5C

  2. Brief communication: NISAR pixel offsets measure but do not statistically resolve pre-failure motion at the 26 August 2026 Bhote Koshi ice–rock avalanche, Nepal. Meena, S. R. EGUsphere preprint, under review for Natural Hazards and Earth System Sciences, 2026. doi:10.5194/egusphere-2026-5462

  3. Masked autoencoding (MAE) outperforms joint-embedding prediction (JEPA) for frozen-probe very-high-resolution landslide segmentation. Meena, S. R., Tang, X., Catani, F. EarthArXiv preprint, 2026. doi:10.31223/X56N4B

Open access

Every NATURA paper is deposited open access.

Data and code

Released with a DOI when the related paper is published.

Looking for something?

Write to smeena[at]ogs[dot]it.

Funding

NATURA, “Assessing Natural and Anthropogenic Drivers of Landslide Risk in Mountainous Regions”, is funded by the Italian Science Fund, FIS 3 call (finanziato dal Fondo italiano per la scienza – Bando FIS 3), Ministry of University and Research (MUR). Project FIS-2024-07495, CUP F53C25000810001. Host institution: OGS. Views expressed here are those of the project team.

Get in touch

Work on landslide risk with us.

We welcome collaborations on landslide inventories, field sites, census and survey data, and on social vulnerability in mountain communities. Write to smeena[at]ogs[dot]it.

NATURA project
Geophysics Department, OGS
Borgo Grotta Gigante 42/C
34010 Sgonico (TS), Italy