Today 7.2 billion people inhabit the Earth and by 2050 this number will haverisen to around nine billion, of which about 70 percent will be living incities. Hence, it is essential to understand drivers, dynamics, and impacts ofthe human settlements development. A key component in this context is theavailability of an up-to-date and spatially consistent map of the location anddistribution of human settlements. It is here that the Global Urban Footprint(GUF) raster map can make a valuable contribution. The new global GUF binarysettlement mask shows a so far unprecedented spatial resolution of 0.4 arcsec($\sim12 m$) that provides - for the first time - a complete picture of theentirety of urban and rural settlements. The GUF has been derived by means of afully automated processing framework - the Urban Footprint Processor (UFP) -that was used to analyze a global coverage of more than 180,000 TanDEM-X andTerraSAR-X radar images with 3m ground resolution collected in 2011-2012.Various quality assessment studies to determine the absolute GUF accuracy basedon ground truth data on the one hand and the relative accuracies compared toestablished settlements maps on the other hand, clearly indicate the addedvalue of the new global GUF layer, in particular with respect to therepresentation of rural settlement patterns. Generally, the GUF layer achievesan overall absolute accuracy of about 85\%, with observed minima around 65\%and maxima around 98 \%. The GUF will be provided open and free for anyscientific use in the full resolution and for any non-profit (but alsonon-scientific) use in a generalized version of 2.8 arcsec ($\sim84m$).Therewith, the new GUF layer can be expected to break new ground with respectto the analysis of global urbanization and peri-urbanization patterns,population estimation or vulnerability assessment.
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