Long-forgotten aerial photographs of Greenland from the 1930s, rediscovered in a castle outside Copenhagen, have allowed researchers to construct a history of glacier retreat and advance in the area.
Most studies of Greenland’s glaciers have been done only since imaging satellites became available in the 1970s, so the data are relatively short-term. But using photographs from 1930s aerial surveys of the southeast coast of Greenland, together with US military aerial shots from the Second World War and recent satellite images, Bjørk and his colleagues have been able to observe changes at high spatial resolution from a period in which few glacier measurements were previously available.
Analysis of the images reveals that over the past decade, glacier retreat was as vigorous as in a similar period of warming in the 1930s
In other words, glacial cycles in Greenland have nothing to do with your SUV.
Left: 1972 image taken by Landsat 1; right, 2010 image taken by Landsat 7, the most recent Landsat satellite.
h/t to Marc Morano