Glacier or Not? The Importance of Nuance in Definitions of Vanishing Glaciers

Allen Pope 

Glaciers provide critical ecosystem services, including water resources, biodiversity, cultural value, and climate signals. But what makes a glacier a glacier? Dierent definitions of what characterizes a glacier can conflict with each other. While a common definition emphasizes "past or present flow," practical applications involve various criteria like currently observable ice flow, crevassing, minimum thickness, minimum area, surficial features related to hydrology and/or debris cover, or relative size. Increasingly, glacier inventories are applying multiple criteria, acknowledging the nuanced, continuous nature of glacier retreat rather than a binary status. In the context of increasingly melting, shrinking, and vanishing glaciers, it is important to explore glacier definitions and their application. Ultimately, the glacier definition applied depends on the specific context, purpose, and audience. This also highlights the need for careful language choice, clear communication, and localized expertise in considering glacier loss.