DRRM ♡ Tsunami

Tsunami

• series of extremely long ocean waves

• caused by a large displacement of ocean water

• “harbor wave” in Japanese

  • highlighting the destruction they cause near coastlines

Tsunami Triggers

• Earthquakes

• Underwater Landslides

• Volcanic Eruptions

• Meteorite Impact

Earthquakes

• shifting tectonic plates

• occurring along trenches and offshore active faults

• not all submarine ____ cause tsunamis

• presence of a vertical component of fault

  movement

Underwater Landslides

• sediment displacement

• displace water due to sediment movement

• occurring under the ocean or coastal landslides

• secondary effects of earthquakes

Volcanic Eruptions

• explosive ocean interactions

• submarine or coastal volcanic activity

• (explosions, caldera collapse, debris avalanches, pyroclastic flows)

Meteorite Impact

• meteorites impacting the ocean can trigger tsunamis

Warning Signs

• onset of a large-magnitude earthquake

• unusual draining of water in the sea (receding tide)

• not wise to wait for an official advisory from PHIVOLCS

How to Escape

• Immediate Action

• Preparation & Safety

• During the Event

Immediate Action

• earthquake is a natural alerting mechanism

• prepare to vacate areas close to the shore

• head towards high ground

• stay informed

Preparation & Safety

• bring a survival kit

• travel light

• designated center

  • stay there until authorities advise

During the Event

• safe routes

  • take escape routes that are safe

• stay away from washed-out roads

  • avoid secondary effects of a tsunami

If Escape is Too Late

• cling on to floating objects

• stay alert at all times

Historical Impact

• 2004 Indian Ocean tsunami (Sumatra)

  • hundreds of thousands perished

• 2011 Japan tsunami

  • 19,300 dead

• 1976 Moro Gulf Tsunami (Philippines)

  • 7,000 died

Aftermath Casualties

• stagnant and contaminated water can lead to illnesses

  • (e.g., malaria, infections)

Environmental Destruction

• soil and forest-moving waves

  • destroy buildings, trees, power lines, bridges, cars, boats, and other objects

Mitigation

• planting deeply-rooting trees and conserving mangroves

  • can help dissipate tsunami energy before it strikes land