Planet’s Data Helped Unravel The Geological And Meteorological Interplay In The Chamoli Disaster

In early February 2021, the Chamoli district experienced heavy rain, leading to flash flooding in the mountainous region. This flooding, combined with a series of interconnected events on February 7, 2021, generated an unprecedented landslide, the generation of a temporary dam in the valley system, and a subsequent breach that impacted local lives and economies.

Getting to the Bottom of the Chamoli Disaster

To better understand the interplay between the factors leading to this landslide, researchers from Aligarh Muslim University and the Indian Institute of Technology Roorkee used Planet satellite imagery. By reviewing PlanetScope data from before and after the event, alongside scientific case studies and published reports, the researchers were able to analyze how the weather events interacted with the unique geological formations of the mountainside to cause such an event.

Their work suggests that a positive feedback system existed between an earlier winter freeze, the rapid flood, wedge rockfall in the region, and erosion in the valley system, leading to the structural instability of the mountain peak and subsequent natural disasters. Planet Dove satellites captured images of the landslide only shortly after the event, revealing a dust and debris path that the scientists could trace to help determine the cause of the landslide.

Disastrous landslide in Chamoli, India, February 7, 2021, Image courtesy of Planet Labs PBC

“There is a need to monitor such extreme hydro-geomorphic events in the vulnerable cryospheric region of Uttarakhand for prospects. The scope of real-time monitoring, analyzing, and alert decimation systems needs to be increased to individual level via mobile phones and public warning systems. An alarming system relying on sensors should be employed for public awareness,” said the authors.

How Do We Harness Satellite Data for Disaster Response?

The Pacific Catastrophe Risk Assessment and Financing Initiative (PCRAFI), a regional flagship initiative of the World Bank, aimed to provide PICs with disaster and climate risk information and associated tools for enhanced risk management to inform development planning and financing decisions. The primary activities included developing an application for Rapid Disaster Impact Estimations immediately following disasters and strengthening the existing Pacific Risk Information System (PACRIS), a database containing detailed, country-specific information on assets, population, hazards, and risks.

Planet’s customer, the Fiji-based Secretariat of the Pacific Community (SPC), used PlanetScope 4- and 8-band products and SkySat tasking to help identify and delineate building and other infrastructure footprints to inform national inventories of infrastructure assets, as well as their exposure to natural disasters. Yet building inventories is just a part of the process; you also need capably trained government agency staff who can use and maintain the data as well as the ability to expand reach and access across the wider Pacific community – particularly when the need arises to communicate risk information to policy and decision-makers effectively.

SPC was able to set up the PACRIS database as a GeoNode location across all of the Pacific nations involved in the project, training over 120 government staff on the platform at its outset in the mid-2010s. The six governments also received Post-Disaster Budget Extension Guidelines, which provide a suite of tools for managing financial demands in the wake of any natural disaster.

SPC has expanded to additional nations like Fiji and Kiribati, and with an eye towards specific-country disaster and climate-risk projects such as providing the analytical inputs to Tuvalu’s policy reforms around reducing risk to public sector infrastructure assets, a flood management plan for the Solomon Islands; and contributed to the technical underpinning to prepare guidelines for the implementation of Fiji’s National Building Code (NBC) for new single-story residential houses and single-story schools located in rural areas.

EXPLORE how Planet data plays a key role in transforming disaster management capabilities amidst the changing climate.

This case study was published in AGIs Oct-Dec 2023 Newsletter on Disaster Management. Click here to view the complete newsletter.

Leave a Comment