What is a earthquake?
A earthquake is a sudden, violent period of ground-shaking
What are the two types of crust?
Dense, thin oceanic crust
Less dense, thicker continental crust
What are the three types of plate margins?
Constructive, destructive, conservative
What is a constructive plate margin?
Plates separate at constructive margins forming new crust, causing volcanic eruption.
What happens at a destructive margin?
Plates collide at destructive plate margin causing subduction, earthquakes, volcanic eruptions and fold mountains
What is a conservative plate boundary?
Plates slide by each other at conservative margins, causing earthquakes
How can risks from tectonic hazards be reduced?
Monitoring, prediction, protection and planning
How to monitor tectonic hazards?
Volcanoes:
• remote sensing- satellites detect heat increases
• seismicity- seismographs record micro-quakes
• ground deformation- laser beams measure changes in the shape of the ground
Earthquakes:
• micro-quakes before the main tremor
• bulging of the ground
• raised groudwater levels
How to predict tectonic hazards?
Volcanoes:
Monitoring is now allowing accurate prediction and effective evacuation
Earthquake:
Accurate predictions are impossible due to lack of clear warning signs
How to protect from tectonic hazards?
Volcanoes:
Little can be done to protect property, but earth embankments and explosive have been used to successfully divert lava flows
Earthquakes:
Earthquakes drills help keep people alert and prepared. But earthquake resistant construction is the best way to reduce risk
How to plan for a tectonic hazard?
Volcanoes:
Risk assessment and hazard mapping to identify areas to practise evacuation or restrict buildings
Earthquakes: risk assessment and hazard mapping to identify areas to protect buildings and infrastructure
What is a tropical storm?
Tropical storm are huge storms called hurricanes, cyclones and typhoons
How do tropical storms form?
•rising air draws evaporated water vapour up from the ocean surface which cools and condenses to form towering thunderstorm clouds
• the condensing releases heat which powers the storm and draws up more water vapour.
• multiple multiple thunderstorms join to form a giant rotating storm
• Coriolis forces spin the storm at over 120km/h creating a vast cloud spiral.
•
What is “super” typhoon Haitian, November 2013?
One of the strongest category 5 storms ever recorded.
Very low air pressure caused 5m store surge swept on shore by winds up to 275km/h.
Coastal devastation included 90% of tacloban destroyed by storm surge
What are the primary effects of ‘Super’ typhoon Haiyan?
• 6300 killed
• over 600000 displaced
• 40000 homes destroyed or damaged
• over 400mm of rain caused widespread flooding
What are the secondary effects of ‘super’ typhoon Haiyan?
• 14 million affected including 6 million jobs lost
• flooding caused landslides
• shortage of power, water, food and shelter, leading to outbreaks of disease
• looting and violence in tacloban
What is a primary effect?
Impacts of strong winds, heavy rain and storm surge
What is a secondary effects?
Long term impacts resulting from primary effect
What are the immediate responses to ‘super’ typhoon Haiyan?
•rapid overseas aid
• us helicopters assisted search and rescue, and delivery of aid.
•field hospitals helped injured
• over 1200 evacuation centres set up
What are the long term responses to ‘super’ typhoon Haiyan?
•UN and international financial aid, supplies and medical support
• rebuilding of infrastructure
• rice farming and fishing quickly re-established
• homes rebuilt in safer areas
• more cyclone shelters built
How can climate change be managed?- alternative energy sources
The burning of fossil fuels accounts for 87% of all co2 emissions. Alternative sources of energy such as hydroelectric power, nuclear power, solar, wind and tides represent sustainable, low carbon alternatives
How can climate change be managed?- carbon capture
Although not yet economically viable, carbon capture and storage uses technology to capture co2 that is produced by burning fossil fuels in electricity generation and industrial processes.
How can climate change be managed?- planting trees
Trees act as carbon sinks, removing co2 from the atmosphere by the process of photosynthesis.
How can climate change be managed?- international agreements
Climate change is a global issue requiring global solutions. Government are negotiating towards a more sustainable future.
