Harvesting remote sensing observations for quantifying burned area and built-up losses from the 2021 wildfires in Greece

Abstract

Mediterranean regions are heavily exposed to wildfires that can result in devastating casualties and infrastructure damage. Greece has been particularly affected by wildfires during recent years and the accurate mapping of the fire-exposed areas is essential. This can enhance our process understanding on such natural hazards, also supporting practitioners and decision-makers. Here, we combined remote sensing observations from the Copernicus Sentinel-2A satellite with GIS techniques to delineate the spatial extent and built-up losses at three example locations over Greece that were substantially affected by the summer 2021 wildfires, namely the regions of Northern Evia, Eastern Attica, and Achaia. The overall burned areas, as quantified with the pre- and post-fire Normalized Burn Ratio (i.e., dNBR), ranged from about 3 km2 to more than 500 km2 , while the exposed built-up features (buildings, roads, etc.) vary between the study regions following site-specific characteristics (built-up density, urban/rural interface, topography, etc.). The combination of publicly available remote sensing Earth observations and GIS techniques allowed us to obtain quantitative insights on the urban features exposed to these wildfires and their variability between the examined locations.