Spatial and temporal variability mapping of future flood hazard affected by climate and land-use changes

ABSTRACT Change of climate and land use can drive and change the frequency of flooding. Moreover, the ensemble method demonstrates reliable efficiency in preparing flood vulnerability maps when integrated with climate and land-use data. In exploring the impact of climate change and land-use changes in the future (2050) on future flood risk, the general circulation model (GCM) with representative concentration pathways of the 2.6 and 8.5 scenarios by 2050 was adopted to understand the impact on eight variable rainfall. The Cellular Automata (CA)–Markov model was also applied to future land use in 2050. To validate it, the receiver operating characteristic–area under the curve (AUC) statistical analysis and other statistical analyses were carried out. The ensemble model showed a good AUC value (0.99) and consistent results across other statistical validation indices, outperforming standalone models. The areas with moderate to very high risk of flooding will increase in 2050. The proportion from the current distribution to 2050 in the Representative Concentration Pathways (RCP) 2.6 scenario changes in the ensemble model. However, this change is more significant in the RCP 8.5 than the current scenario. The integration of ensemble modeling, climate projections, and land-use simulations provides a novel framework for improving future flood assessment and management strategies.