Experimental Landslide Early Warning System for rainfall triggered landslides
An experimental early warning system for rainfall triggered landslides has been generated for the pilgrimage route corridors leading to Badrinath and Kedarnath in Uttarakhand. The early warning system is generated based on the spatial (geological, morphological and terrain factors) and temporal (triggering factors) controls of slope failure. The most widespread triggering factor of landslides in the Himalaya is rainfall and hence the model used rainfall as a trigger for slope failure initiation.
The input to the model are the Landslide Susceptibility Zonation (LSZ) output of NRSC's mapping along the pilgrimage routes of Uttarakhand and Himachal Pradesh , 3 Day rainfall forecast (experimental WRF rainfall forecast data from SAC Ahmadabad) and actual rainfall data of the previous days (gridded point source rainfall data of IMD). For any given day, the system generates early warning for 3 consecutive days starting that day based on the forecast rainfall (for given day and two days ahead) and actual rainfall data for previous 33 days.
This experimental early warning system for rainfall triggered landslides is in the evaluation stage and its reliability needs to established with actual occurrences of landslides during the rainy season.