During one seminar I was asked how bed level changes after a major flood. Quick answer with drone imagery: the top picture is from October-2021 and the bottom one from March-2022, with a major flood in between: December-2021 . Shapes and volumes can be tracked down accurately processing the digital terrain models. Google-Sat background at Alcalá de Ebro. October 2021 March 2022
Officially published by ESA on October 1st, the raw image (2021-09-30) is already available at Google-Earth-Engine , where you can manipulate with a simple code filters and thresholds for edge detection. In this demo we used a true color background shifted to reds, and a Normalized-Difference (B4 red, B11 SWIR 1) index for the lava flow. Check the code here .
At IAPG-Perú , interesting 3x2 hours sessions connecting Perú, Australia and Spain, to discuss real scenarios and how drone footage and numerical models can prevent flash mud-floods on specially steep basins, like the ones of Chosica, Lima, Perú . Links: Promotion