A hydraulic monitor thaws permafrost with high-pressure water in the Klondike goldfields, Yukon — mining exposures that researchers used to access ancient ground ice and fossil records. (Duane Froese), CC BY-NC-ND Permafrost usually hits the news as a hazard; a planetary risk. When this ice-rich ground thaws, it damages roads and building foundations. It drains lakes and tips trees into drunken forests. It releases greenhouse gases that have been locked in carbon-rich soils for thousands of year