Flooding

Flooding monitoring maps where land is inundated, how long water persists, and which communities or assets need response attention.^[1] SAR backscatter change detection is central to flood mapping because microwave observations work through cloud and darkness during storm response.^[1][2] Operational flood maps commonly compare pre-event and post-event SAR acquisitions to detect open water and flood-induced surface change.^[1][3] Flood depth is not directly observed by standard SAR extent products, so depth estimates usually need elevation data, hydraulic context, or LiDAR and DEM integration.^[2] Radar altimetry adds river or lake water-level context, but nadir tracks do not map the full floodplain extent.^[2]