Book excerpt: Once Upon the Permafrost is a longitudinal climate ethnography about "knowing" a specific culture and the ecosystem that culture physically and spiritually depends on in the twenty-first-century context of climate change. Through careful integration of contemporary narratives, on-site observations, and document analysis, Susan Alexandra Crate shows how local understandings of change and the vernacular knowledge systems they are founded on provide critical information for interdisciplinary collaboration and effective policy prescriptions.