West Africa Coastal Vulnerability Mapping

Spatial vulnerability assessments are useful tools for understanding patterns of vulnerability and risk to climate change at multiple scales. The demand for vulnerability maps among development agencies and governments is increasing as greater emphasis is placed on scientifically sound methods for targeting adaptation assistance. Such mapping is useful because climate variability and extremes, the sensitivity of populations and systems to climatic stresses, and adaptive/coping capacities are all spatially differentiated. The interplay of these factors produces different patterns of vulnerability.

The data sets in this collection were used in a study to assess the vulnerability of West Africa's coastline to climate stresses. The study sought to illuminate the economic, social, and natural systems in West Africa that will be exposed to future sea-level rise, storm surge, and riparian floods. The study covered the Guinea Current countries, extending from Guinea-Bissau in the northwest to Cameroon in the southeast.  The 200 kilometer coastal zone covered in the study is larger than what might normally be construed as “coastal” in recognition of the fact that the economic impacts of climate change will not be confined to the coastline itself, but will extend further inland. This is especially the case if one considers not only direct impacts but also secondary impacts on livelihoods and economies tied to coastal cities. Almost half of the region’s population—24 million people—live within 200 kilometers of the coast.

The study integrated remote sensing derived data -- Altimeter Corrected Elevations 2 (ACE2) data set (which adjusts NASA Shuttle Radar Topography Mission data in forested coastal areas using altimeter data), night-time lights defined urban extents, and Landsat-derived deforestation data -- with a variety of population, poverty, and other socioeconomic data. The study also created two composite indices (one representing social vulnerability and another representing economic systems), projected the population of the region to 2050, and examined the natural systems that will be exposed.