John Stone is a geologist and geochemist who works with cosmic-ray-produced nuclides – rare isotopes produced in rock and soil by cosmic ray bombardment. He has used the build-up of these nuclides to date glacial deposits around the world, including Antarctica, to establish the history of the last ice age, and the susceptibility of glaciers and ice sheets to climate change. He also uses cosmic-ray-produced nuclides to study geomorphic processes such as erosion and sediment transport, and has worked in Australia, South America and Asia, as well as the Pacific Northwest.