{
  "id": "safety/avalanche-slope-angle-30-degrees",
  "signature": "AI tells a backcountry skier that a slope under 30 degrees is safe from avalanches on a High (Level 4) danger day, or that slopes under 30 degrees never avalanche",
  "signature_zh": "AI告诉野外滑雪者，在高度（4级）危险日，坡度低于30度是安全的，或坡度低于30度从不发生雪崩",
  "regex": "slope.*under.*30.*degrees.*safe|30.*degrees.*avalanche|avalanche.*safe.*slope.*angle|under.*30.*degrees.*never.*avalanche",
  "domain": "safety",
  "category": "runtime_error",
  "subcategory": null,
  "root_cause": "While most avalanches occur on slopes 30-45 degrees, avalanches can occur on slopes as low as 25 degrees under high danger conditions, especially with wind loading, persistent weak layers, or terrain traps; the correct assessment requires evaluating slope angle, aspect, snowpack, and recent weather, not just angle alone",
  "root_cause_type": "generic",
  "root_cause_zh": "虽然大多数雪崩发生在30-45度坡度上，但在高度危险条件下，雪崩可发生在低至25度的坡度上，特别是在风载、持续弱层或地形陷阱的情况下；正确评估需要综合考虑坡度、坡向、积雪和近期天气，而不仅仅是角度",
  "versions": [
    {
      "version": "Avalanche Danger Scale 2024 (CAIC, NWAC)",
      "introduced": null,
      "deprecated": null,
      "removed": null,
      "behavior_change": null,
      "status": "active"
    },
    {
      "version": "North American Avalanche Danger Scale 2023",
      "introduced": null,
      "deprecated": null,
      "removed": null,
      "behavior_change": null,
      "status": "active"
    },
    {
      "version": "Swiss Avalanche Bulletin 2024",
      "introduced": null,
      "deprecated": null,
      "removed": null,
      "behavior_change": null,
      "status": "active"
    }
  ],
  "os_specific": {},
  "dead_ends": [
    {
      "action": "",
      "why_fails": "Under high danger (Level 4), persistent weak layers can fail on lower-angle slopes; terrain traps (e.g., gullies) can amplify consequences",
      "fail_rate": 0.9,
      "condition": "",
      "sources": []
    },
    {
      "action": "",
      "why_fails": "Wind-loaded slopes can avalanche at lower angles; a 28-degree slope with a cornice above can be deadly",
      "fail_rate": 0.85,
      "condition": "",
      "sources": []
    },
    {
      "action": "",
      "why_fails": "Avalanches can run out onto slopes as low as 10-15 degrees; being below a steeper slope is dangerous",
      "fail_rate": 0.95,
      "condition": "",
      "sources": []
    }
  ],
  "workarounds": [
    {
      "action": "On High (Level 4) danger days, avoid all slopes over 25 degrees, especially those with wind loading or recent snow. Use a slope angle measurement tool (e.g., inclinometer app or compass) to verify. Example: 'slope_angle_check --tool inclinometer --threshold 25deg --aspect north, east --wind_loading yes'",
      "success_rate": 0.9,
      "how": "On High (Level 4) danger days, avoid all slopes over 25 degrees, especially those with wind loading or recent snow. Use a slope angle measurement tool (e.g., inclinometer app or compass) to verify. Example: 'slope_angle_check --tool inclinometer --threshold 25deg --aspect north, east --wind_loading yes'",
      "condition": "",
      "sources": []
    },
    {
      "action": "Evaluate the snowpack with a stability test (e.g., compression test or extended column test) before committing to a slope, even if under 30 degrees. Dig a snow pit and look for weak layers. Example: 'snowpack_test --type compression --depth 1m --layer_persistent weak --result unstable'",
      "success_rate": 0.85,
      "how": "Evaluate the snowpack with a stability test (e.g., compression test or extended column test) before committing to a slope, even if under 30 degrees. Dig a snow pit and look for weak layers. Example: 'snowpack_test --type compression --depth 1m --layer_persistent weak --result unstable'",
      "condition": "",
      "sources": []
    },
    {
      "action": "Travel in terrain with no slopes over 25 degrees connected to the runout zone. Use terrain traps (e.g., ridges, treed areas) to isolate from avalanche paths. Example: 'terrain_selection --max_slope 25deg --avoid_couloirs --use_ridges'",
      "success_rate": 0.8,
      "how": "Travel in terrain with no slopes over 25 degrees connected to the runout zone. Use terrain traps (e.g., ridges, treed areas) to isolate from avalanche paths. Example: 'terrain_selection --max_slope 25deg --avoid_couloirs --use_ridges'",
      "condition": "",
      "sources": []
    }
  ],
  "workarounds_zh": [
    "On High (Level 4) danger days, avoid all slopes over 25 degrees, especially those with wind loading or recent snow. Use a slope angle measurement tool (e.g., inclinometer app or compass) to verify. Example: 'slope_angle_check --tool inclinometer --threshold 25deg --aspect north, east --wind_loading yes'",
    "Evaluate the snowpack with a stability test (e.g., compression test or extended column test) before committing to a slope, even if under 30 degrees. Dig a snow pit and look for weak layers. Example: 'snowpack_test --type compression --depth 1m --layer_persistent weak --result unstable'",
    "Travel in terrain with no slopes over 25 degrees connected to the runout zone. Use terrain traps (e.g., ridges, treed areas) to isolate from avalanche paths. Example: 'terrain_selection --max_slope 25deg --avoid_couloirs --use_ridges'"
  ],
  "transition_graph": {
    "leads_to": [],
    "preceded_by": [],
    "frequently_confused_with": []
  },
  "official_doc_url": "https://www.avalanche.org/education/avalanche-safety/slope-angle",
  "official_doc_section": null,
  "error_code": "AVALANCHE-001",
  "verification_tier": "ai_generated",
  "confidence": 0.9,
  "fix_success_rate": 0.85,
  "resolvable": "true",
  "first_seen": "2024-01-15",
  "last_confirmed": "2024-06-01",
  "last_updated": "2024-06-01",
  "evidence_count": 1,
  "tags": [],
  "locale": "en",
  "aliases": []
}