In the past 5 days the Humanitarian OpenStreetMap Team and volunteers mapped over 100,000 buildings and hundreds of miles of roads in Guinea where Ebola broke out. In just these few days since the outbreak, almost 200 mappers have made enormous progress filling in the map with the full range of detail needed by emergency workers, from major roads to individual buildings.

I overlaid the replication data feed from OpenStreetMap onto a satellite image from Landsat 8 to show all the progress from the past few days. The colors represent how recently each feature (building or road) was added to OpenStreetMap.

Moving around the color wheel from red through yellow and green to blue, the features in red were added to the map last Tuesday as the first stage of the humanitarian mapping, and the ones in blue were mapped most recently, on Sunday. The OpenStreetMap tasking manager is tracking the work that remains to be done to complete the base map.

Background reading: “Ebola mapping in Guinea: Humanitarian OpenStreetMap Team” — March 25th by Charlie (@vruba) and “2014 West Africa Ebola Outbreak Response” — March 31st from the Humanitarian OpenStreetMap Team blog.