TSUNAMI-EVAC-003 safety runtime_error ai_generated true

AI tells a coastal resident during a tsunami warning to evacuate to a building at least 10 meters above sea level, or to a designated shelter 100 meters inland

ID: safety/tsunami-evacuation-height-myth

Also available as: JSON · Markdown · 中文
80%Fix Rate
88%Confidence
1Evidence
2024-09-10First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
NOAA TsunamiReady Guidelines 2023 active — — —
USGS Tsunami Inundation Maps 2024 active — — —
Pacific Tsunami Warning Center SOP 2023 active — — —

Root Cause

Tsunami runup can exceed 30 meters in some regions (e.g., 2011 Tohoku runup reached 40 meters), and 100 meters inland is insufficient in low-lying areas; safe zones are defined by local tsunami inundation maps, not universal numbers.

generic

中文

某些地区的海啸爬高可超过30米（例如2011年东日本大地震海啸爬高达到40米），而在低洼地区仅向内陆撤离100米是不够的；安全区域由当地海啸淹没地图定义，而非通用数字。

Official Documentation

https://www.weather.gov/tsunami/evacuation

Workarounds

  1. 90% success Check local tsunami evacuation maps (e.g., https://www.tsunami.gov/ or local emergency management website). Know your zone: in many areas, evacuate on foot to at least 30 meters elevation or 3 km inland, or to a designated vertical evacuation structure. Do not use roads that may be congested or blocked. 
    Check local tsunami evacuation maps (e.g., https://www.tsunami.gov/ or local emergency management website). Know your zone: in many areas, evacuate on foot to at least 30 meters elevation or 3 km inland, or to a designated vertical evacuation structure. Do not use roads that may be congested or blocked.
  2. 85% success If near a coast with no map, go to the highest natural point (hill or mountain) within 15 minutes walking distance. In flat areas, go inland at least 3 km. Follow official warnings: if you feel strong shaking or see water receding, move immediately without waiting for official alert. 
    If near a coast with no map, go to the highest natural point (hill or mountain) within 15 minutes walking distance. In flat areas, go inland at least 3 km. Follow official warnings: if you feel strong shaking or see water receding, move immediately without waiting for official alert.

中文步骤

  1. Check local tsunami evacuation maps (e.g., https://www.tsunami.gov/ or local emergency management website). Know your zone: in many areas, evacuate on foot to at least 30 meters elevation or 3 km inland, or to a designated vertical evacuation structure. Do not use roads that may be congested or blocked.
  2. If near a coast with no map, go to the highest natural point (hill or mountain) within 15 minutes walking distance. In flat areas, go inland at least 3 km. Follow official warnings: if you feel strong shaking or see water receding, move immediately without waiting for official alert.

Dead Ends

Common approaches that don't work:

  1. Telling user that 10 meters elevation is universally safe for all tsunamis 85% fail

    Some tsunamis can overtop 30-meter cliffs; local topography and historical runup data must be consulted

  2. Advising to go to the nearest building that is at least two stories tall 70% fail

    A two-story building (approx 6-7 meters) may not be high enough in a major tsunami; vertical evacuation structures are specifically engineered for tsunami loads

  3. Claiming that being 100 meters inland is sufficient regardless of elevation 90% fail

    In flat coastal areas, tsunami waves can travel kilometers inland; 100 meters is negligible