US spy satellites inadvertently collected vital environmental data at the height of the Cold War. This trove of photos and data from the Central Intelligence Agency has become crucial to the study of Earth’s environmental changes, as detailed in two fascinating stories in The New York Times this week. One story details the life of a scientist who analyzed them for years, another follows the history of the spy satellites that provided them.
Linda Zall, an environmental engineer, worked at the CIA for decades, leading a team that analyzed images from spy satellites to gather data for environmental studies. She wrote classified reports about how reconnaissance imagery could be used for earth and environmental science, running a research task force that she named Medea, and traveling to Moscow to negotiate the sharing of Arctic data between Russia and the US.
Though the secrecy of the CIA prevented her from being able to publicly take credit for her work, it paved the way for modern scientists to continue using the same methods to study environmental shifts. Declassified images from the Corona satellite project — which collected nearly 2 million images from orbit from 1960 to 1972 — are now used by scientists to track decades of changes around the world, from the movement of glaciers to the erosion of shorelines.
Satellites operated by the CIA have provided vast amounts of environmental data from the 1960s onward that otherwise wouldn’t exist. Other satellite documentation of the Earth’s surface wasn’t collected until later in the century, and being able to look further into the past allows scientists to more accurately predict future changes. Not all of those images are easily accessible though; the majority of Corona’s film has yet to be scanned.
To read the full stories, both of which include comparisons of satellite imagery throughout the years, find the article on Zall here and the history of the Corona satellites here.