Assessment of Flood Susceptibility in Mount Elgon Region of Uganda Under a Changing Climate and Risk Implication to Farmland Food Security

Abstract

Climate extremes, specifically floods, have posed significant challenges to several regions of the world. Mount Elgon in particular experiences severe flood and its’ impacts have drastically affected the region. Climate data used included the monthly observed data blended with Climate Hazards Group Infrared Precipitation with Station data (CHIRPS) for the period from 1991 to 2022 and climate change projections for scenarios under Representative Concentration Pathways (RCP) 2.6, RCP 4.5, and RCP 8.5 from the IGAD Climate Prediction and Application Centre (ICPAC) website. Rainfall trends from the Mann Kendall trend test varied across the seasons, with significant increases in Kapchorwa and Bukwo during the MAM season and uniform trends of intensified rainfall in the SON season while JJA and DJF season exhibited a non-significant increase in rainfall. To analyze flood susceptibility, the Analytical Hierarchy Process (AHP) model reveled rainfall, proximity to rivers, topography and land Use Land Cover as the most flood influencing factors and the weighted overlay integration generated a flood susceptibility map, revealing varying vulnerability levels of moderate to high with an area of 821 Sq.km and 1.6 Sq.km respectively. Furthermore, the study projects increased flood susceptibility in the region under scenarios Representative Concertation Pathways (RCP) 2.6, 4.5, and 8.5 emphasizing an escalating trend in flood susceptible areas, particularly in the northern region. The assessment of potential consequences indicates heightened flood risks in farmlands, particularly in Bukwo district, posing threats to agricultural activities and food production. These findings provide valuable insights into flood susceptibility dynamics and potential consequences considering changing climate condition. The findings underscore the need for proactive measures and adaptive strategies to address the increasing challenges posed by heightened flood risks. These measures are crucial for ensuring environmental resilience and promoting sustainable development in the Mount Elgon region