A paradigm shift in monitoring the Danube Delta (Romania): Insights from Earth Observation Data

The Danube Delta represents a dynamic and vulnerable ecosystem, where monitoring changing processes requires modern analysis tools. This material presents the paradigm shift in monitoring the Delta, illustrating the potential of Earth Observation (EO) data in comparison to classic topographic maps. The study analyzes the vegetation fires of February–March 2025, examined through Sentinel-2, Sentinel-3, MODIS/VIIRS data, burnt area products (EFIS), and Landsat 9 images. The integration of these sources allowed for a detailed observation of the spatial and temporal dynamics of the fires in the first part of 2025, as well as the multi-annual dynamics, starting from the winter 2016–2017 season. Furthermore, the assessment of Sentinel-2 metadata from the 2015–2025 period shows the constant frequency of images with low cloud cover, allowing their applicability in periodic monitoring with a very high temporal frequency. All data were processed in an open-source environment and are freely available, the presented methodology being replicable in other environments. The results underline the importance of EO as operational support in the sustainable management and monitoring of the Danube Delta.