Glaciers—massive and frozen reservoirs of freshwater—range in size from the length of a football field to the breadth of a continent. Photographs, on a much smaller scale, are reservoirs too. They store up a good deal of the data we rely upon to engage with, function in, and document the world. They blanket culture, media and everyday life, just as glacial ice covers vast portions of the globe. Bore down below the surface of glaciers—or photographs—and layers of stratified evidence and meaning re-emerge. Scientists drill, sometimes more than a mile deep into the earth, to extract core samples from ice fields, flecked with dust, ash, traces of atmospheric gas or radioactive substances, even fragments of meteorites. Upon examination they reveal the details of hundreds of thousands of years of climatic history and change. Look deeply and critically enough at the information and narratives embedded in any single photograph and something similar happens as evidence of flash-frozen moments and their motivation resurfaces and falls into place.