SWOT Satellite Reveals Devastating Flood Impact in Rio Grande do Sul, Brazil

In May 2024, the state of Rio Grande do Sul in southern Brazil faced a devastating flood, with the capital city, Porto Alegre, and its metro area being particularly hard-hit. An unusual combination of weather conditions, including a heatwave that blocked a cold front, led to record-breaking rainfall. This resulted in a disaster that claimed 182 lives, left 29 people missing, and displaced over 600,000 individuals from their homes in the whole state. To better understand the scale of the flooding, this study used advanced satellite data and topographic maps to measure how much water was involved, how deep the floodwaters were, and how far they reached. The findings showed that croplands were heavily affected, but within the city, over 420,000 people were directly impacted, including 67,000, especially vulnerable due to social and economic factors. The total volume of floodwater was estimated to be 1.6 billion cubic meters – enough to supply New York City for more than a year. This research helps us better understand the dynamics of floods and can be used to improve disaster preparedness and response in the future.