Spatial mapping of vulnerability to multi-hazards in the savanna ecosystem in Ghana

Produced as part of the Managing climate risks and uncertainties and strengthening climate services CCCEP research programme theme

Abstract

The savannah ecosystem in Ghana is subjected to a number of hazards, including droughts, windstorms, high temperatures and heavy rainfall, the frequency and intensity of which are projected to increase during the 21st century as a result of climate variability and change. Vulnerabilities to these hazards vary, both spatially and temporally, due to differences in susceptibilities and adaptive capacities. Many mapping exercises in Ghana have considered the impacts of single hazards on single sectors, particularly agriculture. But the nature of occurrence of the hazards, sometimes concurrently or alternately, and variability of their impacts on different sectors, warrants the mapping of the vulnerabilities of multiple sectors to multiple hazards. This paper therefore presents an analysis of the spatial dimension of vulnerabilities by mapping vulnerability of sectors that support livelihood activities at a single snapshot in time, using the Upper East Region of Ghana as a case study. Spatial mapping is important as it highlights vulnerable areas and sectors, allowing an integrated and targeted approach for interventions that support adaptation to multiple stresses in the savannah ecosystem. Data collected to develop the maps were largely quantitative and from secondary sources. Other data drew on fieldwork undertaken in the region from July – September, 2013. Qualitative data were quantified by assigning categorical values as the mapping process is necessarily quantitative. Data were divided into susceptibility and adaptive capacity indicators and were mapped in ArcGIS 9.3 using weighted linear sum aggregation. Agriculture was found to be the most vulnerable sector in all districts of the Upper East Region and experienced the greatest shocks from all hazards. Although all districts were vulnerable, the Talensi, Nabdam, Garu-Temapane and Kassena-Nankana West Districts were most vulnerable. Findings highlight the importance of more targeted policy interventions to build adaptive capacity in light of the spatial distributions of vulnerability and provide a first insight into the spatial distribution of hazards across sectors in the Upper East Region of Ghana.