Global Wetland Surface Water Extent Data (1993-2007) - Data Description

Sep 17, 2026

Dataset description for gridded surface water extent over land at an equal-area 0.25°×0.25° grid at the equator, with 773 km² per grid cell. Monthly values are provided for 15 years (1993–2007) for each pixel, where non-inundated pixels and land with snow/ice and coastal pixels are set to -99.00. Includes Fortran-style reading guidance and notes on derived global annual maximum maps and latitudinal distributions.

LanguageEnglish

CategoryResearch & Report

FormatPDF

Pages2

Reading Time5 min

AccessFree to download

Data format

Grid resolution and units

Missing/non-inundated pixel handling

Time coverage and month indexing

Derived global summaries

Annual maximum surface water extent map

Latitudinal distribution comparisons

References

File: wetland_global_extent_ 1993_2007_Papa_etal_2010_Prigent_etal_2012.dat Description: The data are gridded on an equal area grid of 0.25degx0.25deg at the equator. Each grid is 773km in surface. The file contains the surface water extent for each month for 15 years (1993-2007) for each pixel on the land surfaces. Non-inundated pixels, as well as land pixels with snow or ice and coastal pixels, are set to-99.00. To read the ascii file in fortran: c integer icell, imonth c real alat, alon, surf(180) read(30,*) icell, alat, alon,(surf(imonth),imonth=1,180) c icell = for internal use only c alat = latitude between-90 and 90 of the center of the pixel c alon = longitude between 0 and 360 of the center of the pixel c surf(imonth) = wetland surface in km2 (from 0 to 773) for the month for the 773km2 pixel imonth=1,180 for 01/1993 to 12/2007 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; Global map of the annual maximum surface water extent (averaged over 1993-2007) derived from the multi-satellite method. The spatial resolution is 773 km2 (i.e., equal area grid of 0.25°x0.25° at the equator). Also shown are the latitudinal distributions of global surface water for three estimates: 1) the annual maximum surface water extent averagedover 1993-2004 (as shown on the map, solid black line), 2) the maximum surface water extent reached for each pixel over 1993-2007 (broken black line) and 3) the surface water extent from the Global Lakes and Wetlands Database (GLWD Level 3, red line) from Lehner and Doll [2004] . Surface water extent values are aggregated in steps of 3 degrees. Adapted from Papa et al., 2010 and Prigent et al., 2012. References: (available [http://www.legos.obs-mip.fr/papa](http://www.legos.obs-mip.fr/papa or)[ or](http://www.legos.obs-mip.fr/papa or) [http://aramis.obspm.fr/](http://aramis.obspm.fr/)~prigent/publication.html) Prigent C., F. Papa, F. Aires, C. Jimenez, W. B. Rossow and E. Matthews (2012), Changes in land surface water dynamics since the 1990s and relation to population pressure, Geophys. Res. Lett., 39, L08403, doi:10.1029/2012GL051276 Papa, F., C. Prigent, F. Aires, C. Jimenez, W. B. Rossow, and E. Matthews (2010), Interannual variability of surface water extent at the global scale, 1993–2004, J. Geophys. Res., 115, D12111, doi:10.1029/2009JD012674 . Prigent, C., F. Papa, F. Aires, W.B. Rossow, and E. Matthews (2007), Global inundation dynamics inferred from multiple satellite observations, 1993-2000, J. Geophys. Res., 112, D12107, doi:10. 1029/2006JD007847 Papa, F., C. Prigent, and W.B. Rossow (2007), Ob' River flood inundations from satellite observations: A relationship with winter snow parameters and river runoff., J. Geophys. Res., 112, D18103, doi:10.1029/2007JD008451 . Papa, F., C. Prigent, F. Durand, and W.B. Rossow (2006), Wetland dynamics using a suite of satellite observations: A case study of application and evaluation for the Indian Subcontinent, Geophys. Res. Lett., 33, doi:10.1029/2006GL025767 . Papa, F., A. Güntner, F. Frappart, C. Prigent and W. B. Rossow (2008), Variations of surface water extent and water storage in large river basins: A comparison of different global data sources. Geophys. Res. Lett, 35, L11401, doi:10 . 1029/2008GL033857 . Papa, F., C. Prigent, and W.B. Rossow (2008), Monitoring flood and discharge variations in the large Siberian rivers from a multi-satellite technique. Surv. Geophys., 29, 297-317, doi:10 . 1007/s10712-008-9036-0 Decharme, B., H. Douville, C. Prigent, F. Papa, and F. Aires (2008), A new river flooding scheme for global climate applications: Off-line validation over South America, J. Geophys. Res., 113, D11110, doi:10.1029/2007JD009376 . Frappart, F., F. Papa, J.S. Famiglietti, et al. (2008), Interannual variations of river water storage from a multiple satellite approach: A case study for the Rio Negro River basin, J. Geophys. Res., 113, D21104, doi:10.1029/2007JD

FAQs

What is the spatial resolution and grid definition of the dataset?

The data are gridded on an equal-area 0.25°×0.25° grid at the equator, with each grid cell corresponding to 773 km².

How are non-inundated pixels and certain land types represented?

Non-inundated pixels, as well as land pixels with snow or ice and coastal pixels, are set to -99.00.

What time range and data granularity are included?

Surface water extent values are given monthly for 15 years, covering 01/1993 through 12/2007, mapped to month indices 1–180.

Sep 17, 2026

Uploaded by Aria Callaghan