d) In 1997 Lisa McKeon, a physical scientist with the United States Geological Survey who works in the park, came across a pair of historic photographs depicting the glaciers she studies.
c) Over the years, countless photos of the majestic park have been snapped, and many of those have become part of the park’s official archive, spanning over a century.
b) It was a lightbulb moment: Why not use the old photos to create a timeline of the morphing glaciers, and add new photos every year?
a) The Repeat Photography Project was born.