Avalanche Terrain Exposure Scale

The Avalanche Terrain Exposure Scale (ATES) is a classification system used to assess how risky a specific area of terrain is for avalanches, based on factors like slope steepness, terrain features, and avalanche history. It ranges from Level 1 (Low risk) to Level 4 (Extreme risk). Level 1 areas have minimal risk, often with gentle slopes and obstacles that prevent avalanches. Level 4 includes steep, open slopes that are highly prone to large, destructive avalanches. This scale helps winter recreationists and professionals evaluate safety, plan routes, and make informed decisions in snow-covered mountainous terrain.