Acacia Johnson. Glacier Study.Hoarfrost crystals stud the walls of a glacial ice cave in southcentral Alaska. These feathery, star like blossoms form on freezing surfaces on cold, clear nights, when water vapor in the air skips the liquid stage and sublimates directly into ice. I was particularly drawn to the dark rocks and sediment preserved inside the ice, which could be thousands of years olda reminder that glaciers shape the landscapes we live in. Acacia Johnson is an Alaskan