The collapse of the Kakhovka dam led to catastrophic flooding, especially affecting the town of Oleshky (Ukraine). The consequences of this incident were serious. Given this situation, I'd like to highlight a Google Earth Engine script to help with dam breach situations.
In summary, the script provides a comprehensive analysis of flood extent and damage assessment and presents the results through visualization. Its function can help emergency response efforts in the event of a dam breach.
Here's a breakdown of its features:
- Load and filter Sentinel-3 data: The script filters Sentinel-3 satellite imagery according to predefined parameters and selects images within a specified date.
- The script calculates the Normalized Difference Water Index (NDWI) of selected images, creating a mosaic. It then generates a flood extent mask by computing the difference between before and after images and applying a predefined threshold.
- To refine flood results, the script incorporates additional datasets and excludes perennial water bodies from the flood mask. Finally, it analyzes pixel connectivity to eliminate those pixels that are connected to neighbors.
- Analyze Population Density: This script loads population density data and calculates the number of people exposed within the flooded area.
- Assess Agricultural and Urban Impacts: The script uses land cover data to estimate affected agricultural land by applying a flood mask to farmland pixels. Additionally, it identifies affected urban areas by applying a flood mask to urban pixels.
- Show Findings: The script generates a panel showing flood conditions, estimated flood extent, number of people exposed, area of farmland affected, and urban areas affected. A legend is also included to explain the color codes used in the visualization.
Are there any other features or features that you think would be helpful in assessing flood extent and damage?
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