A chance discovery of historic photos in a Danish basement has given new insight to researchers studying the ice on Greenland. The photos were found at the National Survey and Cadastre of Denmark, Denmark’s surveying and mapping agency. They originate from the explorer, Knud Rasmussen’s expedition to the southeast coast of Greenland in the early 1930s. The images stored in glass plates were compared to aerial photos and satellite images taken from World War II to the present.