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The following is a description of EFAS v4.7. For an overview of other EFAS releases, please see: EFAS versioning system


EFAS v4.7 enables the visualisation of the new Global Flood Monitoring (GFM) products in the CEMS EFAS map viewer. The GFM provides continuous monitoring of floods worldwide, by automatically processing and analysing in near real-time all incoming Synthetic Aperture Radar imagery acquired by the EU’s Copernicus Sentinel-1 satellites. Here is a summary of the main changes:

The GFM product is based on 3 different flood detection algorithms running in parallel and is composed by 11 different layers, roughly grouped into 4 categories: water bodies (Observed Flood Extent, Observed Water Extent, Reference Water Mask), uncertainty-related (Exclusion mask, Uncertainty values, Advisory flags), S1 data specifics (metadata, footprint, schedule) and impacts estimate (Affected population, Affected land cover).

With a spatial resolution of 20m and a revisit time ranging from 3 to 14 days depending on S-1 overpasses, the full dataset of the product output layers is made available in raster format both separately and in bulk.

The information about the specifics of the GFM products and how to access the data are provided through the GFM Product User Manual and the Product Description Document available here

Technical details

Climatology real-time
Release date2022-12-12 12UTC
In test suite

2022-09-13 12UTC

EFAS internal release

Archiving of data


Reference climatology (for thresholds/ anomalies)1991-01-01 to 2017-12-31
EFAS Historical1991-01-01 to near present
Horizontal projectionETRS89 Lambert Azimuthal Equal Area Coordinate Reference System (ETRS-LAEA)
Horizontal resolution

5 x 5 km

1 x 1 km for TAMIR products

Temporal resolution

6-hourly for medium range-monthly products, 24-hourly for seasonal

1-hourly for TAMIR products for first 6 hours lead time, 6-hourly thereafter