Flood Frequency Mapping

Information content:

Estimation of a series of flood records for a user defined period, typically a season or multiple years, providing flood extent maps and the frequency map associated to these records. The service is developed by CIMA Foundation with WASDI Sarl.

Service Description:

This service is applied over a specified time window, potentially spanning a season or multiple years, to generate a time series of flood extent maps and associated statistics (i.e., the empirical flood frequency map). It leverages SAR and Optical Sentinel imagery covering the Area of Interest (AOI) specified by the user. Each day that a satellite data is available within the chosen period and AOI, the service produces a flood map using optical and/or SAR sources, depending on datataking. These daily maps are then analyzed at the pixel level to determine how frequently each pixel has been classified as flooded, which is subsequently visualized as an empirical flood frequency map.

Spatial Scale of Observation:

The service generates high resolution maps using 20m resolution imagery.

Temporal frequency:

This service provides one-off historical (multitemporal) analysis for a specific Area of Interest defined by the user.

Nature of service:

This is an open source service.

Benefit of service:

The flood frequency mapping service can be used in the risk reduction community in the broad sense to better understand the hazard, thus informing the risk assessment.

Execution Parameters:

  • Area of Interest

  • Start Date and End Date

Input:

  • Sentinel-1 GRD

  • Sentinel-2 L2A

Third Party Input:

Output:

  • “Daily” SAR flood extent maps

  • “Daily” Optical flood extent maps

  • Flood Count Map

  • EO Data Count Map

  • Empirical Frequency Map

NOTE: daily does not mean every day but every day where at least one SAR or Optical satellite image is available.