Global Inundation Extent from Multi-Satellites (GIEMS) dataset at high spatial resolution.
GIEMS-D15 is a high-resolution global inundation map at a pixel size of 15 arc-seconds (approximately 500 meter at the equator). The map was generated by downscaling inundated area estimates from the Global Inundation Extent from Multi-Satellites (GIEMS) (1, 2, 3) bias-adjusted with wetland extents from the Global Lakes and Wetlands Database (GLWD) (4). This initiative is part of a general project to downscale the full dynamics of GIEMS (GIEMS-D) (5, 6).
Methods and results of creating GIEMS-D15 are fully described in Fluet-Chouinard et al. (2015; see below for full citation). The downscaling procedure predicts the location of surface water cover with an inundation probability map that was generated by bagged decision trees using globally available topographic and hydrographic information from the SRTM-derived HydroSHEDS database (7) and trained on the wetland extent of the GLC2000 global land cover map (8).
GIEMS-D15 represents three states of global inundation extent: mean annual minimum (MAMin, total global area: 6.5×106 km2), mean annual maximum (MAMax, 12.1×106 km2), and long-term maximum (LTMax, 17. 3×106 km2). GIEMS-D15 offers a higher resolution delineation of inundated areas than previously available for the assessment of global freshwater resources and the study of large floodplain and wetland ecosystems.
MAMin and MAMax: These estimates, respectively, represent the average yearly minimum and maximum inundation extent derived from a 12-year record of monthly GIEMS data. Together, these two estimates can be interpreted as typical seasonal low and high inundation situations.
LTMax: This inundation extent represents a less frequent state of extensive flooding. It was derived by combining the average 3-year maximum of the GIEMS record with wetland extents depicted in GLWD.
Data Request, User Agreement & Format
GIEMS-D15 is available upon request made to filipe.aires@estellus.fr
Users of GIEMS-D15 must agree to the terms and limitations of a User Agreement that is signed before data distribution.
GIEMS-D15 is available in three formats:
Citation and further reference:
For further details on map generation and validation, as well as for citation, please refer to: