The ASC 'avalanche terrain exposure scale' (ATES) classifies terrain into Simple, Challenging, and Complex. The key characteristic that elevates terrain to 'Complex' is:
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A
Slopes exceeding 45 degrees average angle
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B
Multiple overlapping avalanche paths, exposure on sustained steep terrain, and limited escape options
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C
Elevation above 10,000 feet with frequent wind loading
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D
Presence of terrain traps on a single avalanche path