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Land cover and its changes have a significant impact on society, with effects such as the alteration of water and energy exchanges between the earth surface and the atmosphere, and changes in the sources of greenhouse gases and aerosols, as well as their decline. Moreover, land cover distribution is partially influenced by the regional climate. Hence, changes in land cover are an important element to consider when assessing climate change and its impacts. In this context, land cover at a global scale is an essential variable for understanding the multiple relations between human activities and global change. One important class of land cover is represented by urban areas that have a particularly strong effect on a region’s climate. In most regions, the urban areas only represent a relatively all fraction of the overall land cover. However, despite their rather limited coverage worldwide, the detection and analysis of their extent, the estimation of population density, and the monitoring of population migration are all prerequisites for accurately assessing the impact of human activities on the environment. Further evidence of this is provided in the 2014 United Nations World Urbanization Prospects report stating that 54% of the world’s population resides in urban areas and that this percentage is expected to increase to 66% by 2050. Observations from space can provide unique and much-needed information that enables a better understanding of the evolution of built-up areas and a more successful management of climate change. In this context, Sentinel-1 and Sentinel-2 satellites missions from the ESA Copernicus program can provide a big piece of information to update continuously land cover maps and their changes at higher spatial resolution and globally.