ANALYZING THE IMPACTS OF TROPICAL STORM-INDUCED FLOODING THROUGH NUMERICAL MODEL SIMULATIONS AND GEOSPATIAL DATA ANALYSIS

ABSTRACT: In 2014, heavy to torrential rains brought by tropical storms Agaton and Seniang triggered massive flooding and caused fatalities particularly in Caraga Region in northeastern Mindanao. To better understand and differentiate the impacts of heavy rains brought by these tropical storms to the extent of flooding, we reconstructed the two flooding events through numerical model simulations, and evaluated the differences through geospatial analysis. We focused on the Cabadbaran River Basin (CBR) and adjoining watersheds in Agusan del Norte, Caraga Region as our case study area. The results of this study showed the importance of combining geospatial data and techniques with numerical models to reconstruct and understand past flooding events. The flood simulations and maps derived from this study can be useful not only in flood hazard mapping of the study area, but also as visual aids to help people understand the differences of the impacts of different tropical storms in the occurrence of flooding. On the other hand, results of the study have some practical implications to climate change impact and mitigation studies on the aspect that studying how the current weather and climate scenarios are affecting us (e.g., in terms of flooding) can help us understand and make necessary preparations for a future weather or climate scenario. 1