Satellite-Detected Flood Extents in Malawi, January-February 2022

UNOSAT map TC20220126MWI illustrates cumulative flood extents aggregated from Sentinel-1 radar images acquired between 26 January and 2 February 2022. The analysis used an AI-based method and WorldPop demographic data, estimating about 102,000 people were exposed or living close to flooded areas, primarily in the Chikwawa and Nsanje districts. This is a preliminary analysis produced by the United Nations Satellite Centre (UNOSAT) and has not been validated in the field.

Use Cases

• Assessing population exposure to flooding based on integrated satellite and demographic data.
• Mapping flood extent over time for disaster response coordination based on Sentinel-1 radar imagery.
• Validating AI-based flood detection methods against ground feedback as suggested in the description.

Strengths

• Analysis integrates satellite imagery with spatial demographic data from WorldPop.
• Provides a specific population exposure estimate of ~102,000 people, with district-level breakdowns for Chikwawa and Nsanje (~33,700 each).
• Explicitly documents the methodology as an AI-based analysis of Sentinel-1 radar images.

Limitations

• The analysis is preliminary and has not been validated in the field.
• Flood detection from radar may underestimate standing water in built-up and densely vegetated areas, as noted.
• Row count and column-level documentation are absent; data structure must be inferred from the geospatial files.

Provenance

Source

United Nations Satellite Centre (UNOSAT)

Collection Method

Automated analysis with an AI-based method applied to Sentinel-1 radar images, integrated with WorldPop demographic data.

Time Range

26 January to 2 February 2022

Freshness

Last updated 2026-04-19 10:07:32.409815; freshness should be verified.

Geography

Malawi, specifically mentioning the districts of Chikwawa and Nsanje.