Honshu, Japan- Multi hazardous environment Flashcards
Nature and risks of the hazards felt here?
Volcanoes:
- 47 located on the island
- Create lava flows, explosions and landslides
Earthquakes/tsunamis:
- Earthquakes with a magnitude of over 6 account for 20% of global incidents.
- Building/infrastructure damage, may affect economy.
Typhoons:
- 30% head north of equator towards Japan.
- High winds and flooding.
- Building/infrastructure damage.
Impacts of the Tohoku earthquake?
- 18,000 people dead, injured or missing.
- Tsunami wave hit coast 30 mins after earthquake, 10km inland.
- 150,000 in temporary shelters and emotionally traumatised.
- Radiation leaks at Fukushima power plant due to tsunami.
Nature of the Tohoku earthquake?
- Focus 19 miles deep.
- Magnitude 9.
- Epicentre 100km out to sea.
- Pacific plate subducted below the North American plate
Short term and long term responses to the Tohoku seismic event?
Short term:
- 100,000 soliders to establish order and distribute food, water, blankets etc.
- Rescue workers by foot, boat and helicopter.
- Survivors of tsunami huddle in shelters.
- Exclusion zone around Fukushima nuclear plant.
Long term:
- New tsunami warning system in place.
- Advisory body set up to deal with reconstruction and long term growth in area.
- Reviewed height of the tsunami wall as not high enough to protect.
Adaptation, mitigation, or prevention of seismic events in Japan?
- DART tsunami warning system alerted area - 30 mins before.
- Earthquake warning system issued alerts via TVs and phones.
- UrEDAS train system shut off all power to trains when waves felt.
- Aseismic and retrofitted buildings
Why would people continue to live in these areas despite being constant risk?
- Culture
- Family/ livelihood
- Expensive to migrate
- May feel they are protected due to the warning systems etc already in place.
What is a fatalistic attitude and why would it benefit people living here?
In areas struck by natural disaster fatalism can be a positive outlook for those living in these areas as they believe that although they cannot prevent the disasters they are able to just continue with life and will not let it hold them back.
Japans prevention strategies:
As a HIC Japan are abel to protect and mitigate the effects felt by the event they have done this in ways such as:
- Aseismic designed buildings allow buildings to sway due to foundations which slide and bend with supported structures.
- Retrofitted buildings is where existing structures are strengthened and made earthquake proof by adding steel cross based frames.
- Sea walls, failed in 2011 as not high enough to stop 10m wave.
- Store flood waters in gigantic storage tanks and 6km of underground pipes to lessen flooding.
- Warning systems issue alerts e.g. DART
What risks are caused by the volcanos on the island of Honshu?
Social risk:
- Ash could cause respiratory and other health issues with people who are directly affected e.g burns.
- Could disrupt travel due to the pyroclastic explosion which would cover huge area in ash.
Economic risk:
- Mt Fuji would have to close as a tourist destination which could lead to financial loss.
- Disruption to flight and travel companies, which could cause substantial financial loss.
- If major cities are blocked this will also result in a loss of earnings.
Environmental risk:
- Destroy habitats and biodiversity.
- Contribute to climate change as huge amounts of co2 is released.
- Ash will block the sunlight which will mean no photosynthesis, positive feedback - contributes further to climate change.
- Ash will contaminate the local water cycle.
Why do people continue to live in the area affected by volcanic eruptions in Japan?
People continue to live in the area due to the many adaptation and mitigation strategies in place:
- Created channel works to block and divert the lava from built up areas.
- Continually monitoring the volcano so they know when an eruption is about to occur so they can begin the evacuation strategy.
- Created an evacuation zone based on past eruptions which will limit death and injury.
- Are extremely resilient to these hazards as they are just part of their daily life so will just accept and try to move on.
Typhoon Lan, October 2017:
Nature of the storm:
- High winds, 800mm in 72 hours, 170kmph, category 4.
Impacts:
- 20,000 evacuated
- 17 dead
- Roads blocked by floodwaters causing mudslides
- Damage to buildings and cancelled flights
Adaptation and mitigation:
- New buildings are encouraged to be built of wood using cross bracing for strength
- Are issued with advice of what to do when events occur
- Giant underground flood tanks to store floodwaters
Culture of risk prevention:
- Put together a disaster reduction to reduce deaths and economic loss.
- Trained 40,000 people in disaster recovery also increase Japans international capacity to help elsewhere
- Heavy signage for evacuation shelters
