By Carl Franzen
If you are a climate scientist trying to study the amount of sea ice on Earth poles over time, it make senses to look at as many satellite images of Antarctica and the Arctic as you can get your hands on. But the satellite record of sea ice only extended as far back as 1979 — at least until recently. As Barents Observer reports, a climate scientist named David Gallaher at the US National Snow and Ice Data Center (NSIDC) in Colorado recently managed to painstakingly recover old satellite data from the early 1960s captured by vintage NASA Nimbus satellites. The process was an elaborate one: Gallaher and his colleagues had to sift 25 boxes full of 200-foot-long (60-meter) reels of 35-millimeter film, digitize them using a vintage film reader, and then match them to the location of the satellites in orbit so they could pinpoint the exact location of the photos.
That latter part proved perhaps most challenging, as the record of the orbit was kept in separate infrared imagery, which also had to be processed on its own. In the end, the scientists managed to recover more than 250,000 images, over 90 percent of the data, which they have made public on the website. Already, the data has yielded new insights about the climate, showing larger areas of sea ice in the Arctic on average in the 1960s than we have today, and a huge swing in sea ice in the Antarctic. Aside from yielding new insights about Earth's climate, the new images make for some pretty cool wallpapers, too.