A new high resolution historical aerial image dataset from East Greenland

During the last decades the high Arctic has undergone substantial changes as a result of global warming and arctic amplification. Melt seasons are expanding rapidly, and landscape and ecosystems are shifting into new states. To quantify these changes from the historical baseline requires datasets on pre-warming states, which can be extremely rare in the high Arctic. Prior to the satellite era, starting in the 1990s, a commonly used data source for baselines in geosciences is aerial photographs, which if one is lucky can reach back to the 1930s. These aerial images are most often recorded at high elevation and perhaps also obliquely which results in spatial resolutions of 2-10 meters, limiting the level of detail that can be resolved on the ground.  

With this presentation we reveal a new exciting dataset of aerial images from East Greenland recorded in the 1950s and ‘60s. Contrary to other aerial campaigns, these images were recorded at very low elevation in order to conduct geological mapping, ultimately yielding spatial resolutions surpassing those of the newest high resolution satellites.

The images were recorded by geologist John Haller during the Lauge Koch expeditions to central East Greenland in the 1950s and 1960s, and comprise a dataset of c. 3600 high resolution oblique images recorded at low elevation from plane and helicopter. The images are recorded in stereo, which allows us to recreate the terrain surface in 3D and construct orthorectified imagery that allows a direct comparison with modern satellite images, for use in all aspects of landscape- and ecosystem evolution.