Spatial understanding of historical and future landslide variation in Africa

The African natural landscape reshaping in search for housing, food and infrastructure development exposes the slope to failure. However, the entire African landslide characterization is still not well known due to limited studies covering the whole continent. The authors recognize this fact and conduct this study to present the historical landslide susceptibility (1990–2020) and the 2050 predicted occurrence under urbanization practices in Africa. The 1982–2021 reviewed literature identifies 26,211 recent landslides and high number is localized within same areas highlighted by the 2007–2018 Global Landslide inventories. For periodical landslide susceptibility mapping, rainfall, urbanization and LULC are selected as major drivers based on literature and inventory. These factors’ historical maps are estimated to date (2022) and combined with other landslide causal factors namely elevation, slope, aspects, curvature, distance to roads, distance to rivers, distance to faults, soil moisture, soil texture and lithology as of 2022. GIS facilitated to estimate current (2022) landslide susceptibility. The Information Gain Ratio sensitivity analysis highlights urbanization (0.106), LULC (0.097), slope (0.091), elevation (0.088) and rainfall (0.083) as key landslide drivers. The Southern and Horn of Africa seize over 80% of high and very high susceptibility, respectively. This 2022 susceptibility map is then predicted to 2050 and reclassified as that of 2050 urbanization (base map). The Southern, Eastern, Northern and Horn of Africa are future landslide prone areas. This new study helps policymakers to ensure proper/suitable land and urban planning and management practices for sustainable urbanization and lowering loss on human lives, damage on properties and environment.