Evaluating flood events caused by Medicane “Daniel” in the Thessaly District (Central Greece) using remote sensing data and techniques

On September 4, 2023, Thessaly, Greece, underwent a catastrophic flood due to Medicane Daniel.Extreme rainfall, ranging from 305 mm to 1096 mm between 4 and 12 September, caused extensive damage to the infrastructure, agriculture and houses.Seventeen casualties were recorded.This study is aimed at using radar data from earth observation satellites to detect the inundated areas and evaluate the impact of the flood.Sentinel images were acquired from Copernicus Open Acess Hub For 7, 10, 13, and 19 September, 2023, along with a CORINE Land use/Land cover map.Processing the satellite images involved several steps, including their calibration, noise removal, filtering, and polarization adjustments.Flooded areas were quantified for the specified dates, thereby revealing substantial coverage of the land.The damage assessment focused on irrigated and non-irrigated land and pasture areas, highlighting the impact's severity.The highest impact was noticed on September 7 in irrigated land (95.62%).The second phase incorporated the Flood Water Depth Estimation Tool (FwDET) to estimate the floodwater depths and reveal the maximum depths near riverbanks.The maximum floodwater depth was also noticed on September 7 and reached 9.49 m.This study employed advanced remote sensing and GIS techniques, allowing for a rapid estimation of flood characteristics and assessment of Medicine Daniel's damage to the Thessaly prefecture from September 4 to 12, 2023.