Table 3.

Reference layers. Reference.

Reference Layer	Description	Coverage
Relief Mask [DLR-RM]	Binary mask generated using the SRTM DEM for latitudes between −60° and +60° and the ASTER DEM elsewhere. It is labelled as positive where the shaded relief is greater than 212 or the roughness is greater than 15.	Global
OSM-Settlements [OSM-S]	Binary mask labelled as positive in correspondence of settlement-related OpenStreetMap geometries.	Global
OSM-Roads [OSM-R]	Binary mask labelled as positive in correspondence of road-related OpenStreetMap geometries.	Global
DLR Road Cluster [DLR-RC]	Binary mask obtained applying focal mean filtering to the OSM-R dataset.	Global
GLC30-Settlements [GLC30-S]	Binary mask labelled as positive in correspondence of GLC30 class 80 (i.e., artificial surfaces).	Global
GLC30-Water [GLC30-W]	Binary mask labelled as positive in correspondence of GLC30 class 50 (i.e., water).	Global
GLC30-Wetlands [GLC30-WL]	Binary mask labelled as positive in correspondence of GLC30 class 60 (i.e., wetlands).	Global
Copernicus Imperviousness Layer 2012 [CIL]	Binary mask labelled as positive where the Copernicus Imperviousness Layer 2012 exhibits values greater than 30%.	Europe
US National Land Cover Dataset 2011 [NLCD]	Binary mask labelled as positive in correspondence of classes 22, 23 or 24 from category “Developed” of the US National Land Cover Dataset 2011.	USA

layers used in the post-classification phase.