Thanks to the data provided by Sentinel 1 and 2 satellites and the algorithms developed by CIMA Research Foundation, it was possible to process the maps of the flooded areas in north-western Italy on the night between October 2nd and 3rd, in about 12 hours
Following the floods that hit the North-West of Italy between October 2nd and 3rd, 2020, the Italian Civil Protection Department requested CIMA Research Foundation, Competence Center for Hydrogeological Risk, the mapping of of the flooded areas observed by Earth satellite data. CIMA Research Foundation used data from Sentinel-1 radar satellite, able to provide day and night images in any weather condition, and data from the Sentinel-2 multispectral satellite, which provides images during the day and in the absence of cloud cover.
Both satellites observed the area of interest on Saturday, October 3rd, allowing to assess the extent of the flooded areas at two different times during the day: Sentinel-2 data were acquired at 12.20 pm and Sentinel-1 data acquired at 7.25 pm. Three maps were generated using algorithms developed by CIMA Research Foundation for the mapping of flooded areas, . These maps, produced in about 12 hours from the availability of the images in the catalog, show the situation in the area of Vercelli and Ventimiglia seen by Sentinel-2 (at 12.20 pm) and the situation in Piedmont observed by Sentinel-1 at 7.25 pm. The permanent waters are represented in blue, while the flooded areas are represented in light blue. It is possible to notice the effect of the flooding of the Sesia river (Vercelli), given the presence of several celestial areas adjacent to the river itself. The flooding of the Roja river (Ventimiglia) is also clearly visible.
