As part of a joint project between Ghent University, the Ethiopian Geospatial Information Institute and Mekelle University, the aerial photographs of the 1930s have been digitised; about 40% of them could be relocated through comparison with recent satellite imagery, and have been organised into a searchable inventory.

So far, the aerial photographs of this collection have been used for research at local scale, addressing changes to rivers, to land use, or to density of soil and water conservation. Also urban expansion, gully development, church forests or lake level changes have been studied. But much more remains to be done.

Methods used include the recognition of features by morphology and texture on the photographs, image restitution through modelling methodologies, or simple ‘rubbersheeting’, counting of number of features for a given area, point-count method...

Aerial photo archive of Ethiopia in the 1930s

The archive of pre-1940 aerial photography of Ethiopia comprises the coverage of north and central Ethiopia that was acquired during the Italian invasion of the country in 1935-36 and during the period of occupation. This activity ceased after the defeat of the Italian army in East Africa in 1941.

The rediscovery of this archive opens new perspectives for change studies as it is the largest set of pre-1940 APs in Africa.

As a result of an agreement between Ghent University (Belgium), the Ethiopian Mapping Agency (now Ethiopian Geospatial Information Institute) and Mekelle University (Ethiopia), all the photographs in the archive have been digitised at a resolution of 600 spi.

In total, the archive comprises approximately 34,000 individual photographs, made up of 8281 discrete assemblages, each comprising four adjacent photographs.

Photographs bear no fiducials and merely a two- or three-digit identification number.

An individual set of four photographs comprises a vertical (nadir-pointing) photograph, flanked by two low-oblique photographs and a single high-oblique photograph, which is present alternatively at left and right. All four photographs had been exposed simultaneously in a fan configuration in the cross-track direction (perpendicular to the flight line) to ensure the widest possible angular coverage of the terrain.