"Evolution of Built Surfaces Based on Copernicus High Resolution Layers. The Case of Growth Poles-Based Metropolitan Areas, Romania "

The evolution of built areas is a widely debated subject mostly because their high dynamics and expansion can be related to the economic development. Technically, the availability of European datasets that include the built areas extracted from satellite imagery is an advantage that could be used for further research. The study aims to analyse the spatial and temporal dynamics of the built areas in six metropolitan areas of Romania, in the period 2006-2018. Functional areas were delimited and the new cover of built areas was calculated for each administrative unit. The Imperviousness Classified Change datasets for the periods 2006-2009, 2009-2012, 2012-2015 and 2015-2018 were downloaded in raster format from Copernicus Land Monitoring Service website. The new surfaces, added from one period to another, were outlined in cartographic representations and Google Earth was used for validation. The results showed that, for the entire reference period, the largest increase values of the newly built area were registered in the metropolitan areas of Cluj, followed by Braşov and Timişoara, whilst lower increase values were recorded for Constanţa, Craiova and Iaşi. Also, by analysing the extension of the built areas, we were able to illustrate some spatial development directions within each of the metropolitan areas. The major differences can be explained by the economic development of the examined areas, which included the expansion of both residential and transport infrastructure. Moreover, the pace of development was more intense in the case of the administrative units located nearby the urban centre as opposed to those situated at a considerable distance. This conclusion emphasises the importance of proximity within the metropolitan area studies.