The GLWD-3 dataset comprises lakes, reservoirs, rivers, and different wetland types (Table 4) in the form of a global raster map at 30-sec resolution. It was produced by the Center for Environmental Systems Research (CESR), the University of Kassel, Germany, and the World Wildlife Fund, Washington DC, USA (Lehner and Döll 2004), based on various data sources, mostly 1970s to 1990s. The GLWD-3 dataset may serve as an estimate of wetland extents for global hydrology and climatology models, or to identify large-scale wetland distributions and important wetland complexes. It is supplemented by GLWD-1 and GLWD-2.