Towards an Operational InSAR Framework on HPC for Time-Critical Landslide Precursor Detection and Early Warning

Timely detection of landslide precursors is essential for life-saving early warnings, yet remains challenging due to the subtle, non-linear nature of pre-failure ground motion and the computational intensity of processing SAR time series. To address this, we present an operational automated InSAR framework, co-developed under India’s National Supercomputing Mission and the India-EU GANANA HPC collaboration, that processes multi-temporal SAR data optimized on HPC infrastructure (AIRAWAT) to enable long-term satellite-based monitoring large areas for landslide hazard assessment and early warning.

The system ingests Sentinel-1 SLC, IW data and ancillary geospatial layers (DEM and historical landslide inventories). Using GMTSAR-automated workflows, it generates displacement time series and LOS velocity maps across large, landslide-prone regions. These outputs are analysed to identify accelerated displacement trends for known landslides. Threshold values are identified based on the movement signatures, key precursors to slope failure, days to weeks before catastrophic events.

Critically, the entire pipeline, from SAR data ingestion to risk classification, is optimized for low-latency execution on HPC, enabling updates within 24–48 hours of new satellite acquisitions. Outputs are translated into a dynamic risk alert system (Green–Red) and delivered via an interactive dashboard with API access, designed for integration into national disaster response workflows.

Currently piloted in the Himalayas and Western Ghats, this framework demonstrates a scalable, HPC-driven paradigm for time-critical geo-hazard monitoring directly supporting rapid situational awareness and proactive evacuation decisions. The architecture is extensible to other InSAR-monitored hazards (e.g., subsidence, volcanic unrest).

The framework was tested with the well-documented Nepal Earthquake (7.8 M) on 25 April 2015, which triggered more than 47,200 co-seismic landslides. The displacement and coherence time-series were plotted at the crown points and centroids of the landslide polygon. The time-series plots show prominent trends towards the event date. Significant peak was observed in the displacement derived from 08 February 2015 and 21 April 2015 (Sentinel-1 Ascending) interferogram, which may be used as an early warning precursor.