# A Visualization Tool for Flood Dynamics Monitoring Using a Graph-Based Approach
## 6 Conclusions  
In this letter we have successfully distilled a flood dynamics map from a radar SITS. The resulting global variation map evaluates floods, not only in terms of extent and duration, but also in terms of spatio-temporal variation. These insights into flood dynamics can therefore serve in operational frameworks for multiple applications. For example, this method can point out locations to be monitored to improve a hydraulic model (in the context of data assimilation) or the locations in need of damage relief (in the context of disaster management). Moreover, the framework is fast, effective and simple. By using 2 exemplary flood cases, further upscaling is expected to go smoothly. Computation time increases with the number of entities, rather then with an increase in area. Since the method is generically deployable, it could be applied to different types of (natural) phenomena (e.g., snow, vegetation). Future research will include further upscaling to country/continent scale, analysis of longer timeseries, and inclusion of different sensors and platforms (e.g., Sentinel-2).  
The following are available online at [[http://www.mdpicom.com/2072-4292/12/13/2118/s1](http://www.mdpicom.com/2072-4292/12/13/2118/s1)]([http://www.mdpicom.com/2072-4292/12/13/2118/s1](http://www.mdpicom.com/2072-4292/12/13/2118/s1)), Figure S1: Comparison for Mozambique of Otsu tiled thresholding and Unisat flood map on 14 March 2019 (Timestep 2), Figure S2: Comparison for Mozambique of Otsu tiled thresholding and Unisat flood map on 26 March 2019 (Timestep 3), Figure S3: Comparison for Mozambique of Otsu tiled thresholding and Unisat flood map on 26 March 2019 (Timestep 4), Figure S4: Comparison for Mozambique of Otsu tiled thresholding and LIST flood map on 20 March 2019 (Timestep 3), Figure S5: Comparison for India of Otsu tiled thresholding and Sentinel Asia flood map on 30 September 2019 (Timestep 3), Video S1: Mozambique pre-processing results, Video S2: Mozambique flood delineation, Video S3: Mozambique variation, Video S4: India pre-processing results, Video S5: India flood delineation, Video S6: India variation, Figure S6: Additional temporal profile and variation evolution for water body in India (graph 10501), Video S7: Spatial evolution of water body in India (graph 10501), Figure S7: Unified flood map Mozambique.  
[PERSON] and [PERSON] designed the workflow and the computational framework. [PERSON] carried out the implementation and performed the calculations. [PERSON] coded the script for Otsu tiled thresholding. [PERSON] wrote the manuscript with input from [PERSON] and [PERSON]. All authors have read and agreed to the published version of the manuscript.  
This research was funded by Special Research Fund (\"Bijzonder Onderzoek Fonds\" or BOF) of Ghent University, grant number BOF.STA.2017.0033.01.  
The authors are grateful to the Luxembourg Institute of Science and Technology for providing their version of the Mozambique flood extent map.  
The authors declare no conflict of interest.  
The following abbreviations are used in this manuscript:  
\begin{tabular}{l l} ESA & European Space Agency \\ GRD & Ground Range Detected \\ LIST & Luxembourg Institute of Science and Technology \\ MUM & Minimal Mapping Unit \\ ROI & Region Of Interest \\ SAR & Synthetic Aperture Radar \\ SITS & Satellite Image Time Series \\ \end{tabular}