Tsunami Hazard Maps for Southeast Alaska Communities

A hazard assessment for coastal communities in Southeast Alaska models tsunami waves from four megathrust earthquake scenarios. The study provides maximum runup heights of 4 meters for Port Alexander, 3.2 meters for Craig, and 1 meter for Ketchikan. Results are intended to guide emergency management agencies in evacuation planning and public education.

Use Cases

• Compare maximum runup heights across Port Alexander, Craig, and Ketchikan to prioritize community-level mitigation resources.
• Validate numerical tsunami models for the Gulf of Alaska using the four hypothetical earthquake scenarios described in the report.
• Integrate approximate tsunami hazard maps with local geographic data for initial evacuation zone planning.
• Analyze the threat from far-field tsunamis originating along the Alaska-Aleutian subduction zone for regional preparedness.

Strengths

• Provides concrete maximum runup height measurements for three specific communities.
• Models tsunami impacts from four distinct, well-defined megathrust earthquake scenarios.
• Focuses on a defined geographic region: coastal communities in Southeast Alaska.

Limitations

• The dataset scope is limited to three primary communities, with others like Saxon and Mountain Point mentioned but not detailed.
• Results are based on hypothetical scenarios and numerical models, not historical tsunami observations.
• The underlying digital data format, column structure, and sample size are not described in the input.

Provenance

Source

State of Alaska, Division of Geological & Geophysical Surveys (DGGS).

Collection Method

Numerical modeling of tsunami waves generated by hypothetical megathrust earthquakes.

Freshness

Data was last updated on July 5, 2023.

Geography

Coastal communities in Southeast Alaska: Port Alexander, Craig, Ketchikan, Saxon, and Mountain Point.