West Africa Coastal Vulnerability Mapping: Subset of JRC Map of Accessibility

Extensive literature shows that road networks and market accessibility play an important role in development and access to health care and other social services. Greater spatial isolation is assumed to produce higher vulnerability to climate stressors.

Market accessibility is defined as the travel time to a location of interest using land (road/off road) or water (navigable river, lake, and ocean) based travel. A team at the Joint Research Centre (JRC) in Ispra, Italy, created a global raster of accessibility using a cost-distance algorithm which computes the "cost" (in Units of time) of traveling between two locations on a regular raster grid. The raster grid cells contain values which represent the cost required to travel across them, hence this raster grid is often termed a friction-surface.