Natural hazards Flashcards
What is a constructive plate boundary?
Where two plates move apart/ away from each other.
What is a distructive subduction plate boundary?
Where two plates of different density move towards each other.
What happens at a conservative plate boundary?
Where two plates slide past each other.
What is destructive collision plate boundary?
Where two plates of the same density move towards each other.
What is subduction?
One plate going under another plate.
What is density?
How compact/ heavy something is.
What are seismic waves?
Waves of energy that travel through the earth
What is focus?
The point inside the earths crust where the earthquake originates.
What is the epicentre?
The point on the Earths surface direct above the focus of an earthquake.
What is the Richter Scale?
A logarithmic scale that measures an earthquake’s magnitude based on the size of its seismic waves.
What is the moment magnitude scale?
A logarithmic scale that measures earthquakes by estimating the total energy released.
What is an effect?
An impact that is caused because of the natural disaster and hazard.
What is a response?
What people and organisations do in the short- and long-term after a disaster.
What are primary effect?
The immediate impact caused directly by a hazards.
What are secondary effect?
Occur indirectly from the hazard, often as a result of primary effects.
What are immediate response?
Happen just before, during or right after hazards.
What are long term response?
Later reactions that occur in the weeks, months and years after the event.
What is monitoring?
Using scientific equipment to detect warning signs.
What is prediction?
Using historical historical evidence and monitoring, scientists can make predictions about when and where a tectonic hazard may happen.
What is protection?
Designing buildings that will withstand tectonic hazards.
What is Planning?
Actions taken to enable communities to respond to, and recover from, natural disasters.
What is global atmospheric circulation?
A worldwide system of winds, which transport heat from tropical to polar latitudes.
Where is low pressure?
0 and 60 degrees
Where is high pressure?
30 and 90 degrees
What weather is found at low pressure?
Cloudy conditions
What weather is found at high pressure?
Clear skies
What are trade winds?
Winds that blow from the tropics towards the equator from the east to the west
What is a weather system is a tropical storm?
Low pressure
How do tropical storms form?
.solar radiation from the earth heats the ocean to 27 degrees
.low pressure occurs as air rises
.air cools as it rises and it condenses.
.this causes huge amount of energy to be released which makes thunderstorms develop
.air rushes from high pressure to low pressure creating winds
.the storm begins to rotate due to the Coriolis effect
.some cool air sinks back down, making the eye
What are rain bands?
A band of dense clouds that swirls around the eye wall of a hurricane
Where are cyclones?
The Indian Ocean
Where are hurricanes?
The Atlantic Ocean
Where are Typhoons?
The Pacific Ocean
What is the Saffir-Simpson scale?
Hurricane intensity scale that measures hurricane wind speeds. Measures strength from category 1-5
Definition of natural hazard?
A natural event that has the potential to cause damage, destruction and death.
What are the hazard risks?
.Magnitude
.Location
.Time
.Wealth
.Education
.frequency
.Natural factors
.population density
Key facts about Oceanic crust
.Younger
.thinner
.denser
.can sink
.can be renewed or destroyed
Key facts about continental crusts?
.Older
.Thicker
.Less dense
.cannot sink
Can’t be renewed or destroyed
What is oceanic crust made from?
Mainly basalt
What is continental crust made from?
Mainly made from granite
Where do the majority of earthquakes form?
Destructive subduction plate boundary
What forms at a destructive collision plate boundary.
Fold mountains, earthquakes
What forms at destructive subduction?
Violent volcanic eruptions, earthquakes, composite volcanoes
What forms at constructive plate boundaries?
Gentle volcanic and earthquake activity
What occurs at conservative plate boundary?
Violent earthquakes
What direction do tropical storms travel?
West
How meany people died and were injured in Christchurch?
181 died and 2000 injured
How meany buildings were destroyed in Christchurch?
Half
What was the cost of recovery in Christchurch?
$11 billion
Secondary effects of Christchurch?
.Couldn’t hold 5 World Cup matches
.10000 people migrated
When was Christchurch hit with an earthquake?
22nd feb 2011
Where was the location of the epicentre in Christchurch?
10km south east of Christchurch
Immediate responses from Christchurch?
.Aid workers came to help (e.g Red Cross)
.300 Australian police officers were flown in
.military was mobilised to help rescue effort
What type of plate boundary was the christchurch earthquake?
Conservative and 5km deep
Long term responses from Christchurch?
.Water and sewerage were restored by August 2011
.Goverment set up the “Canterbury Earthquake Recovery Authorities” cost 13 billion
.city was spit into 4 zones to see which they needed to rebuild first
How meany were injured and killed in Nepal?
9000 died and 20000 injured
Primary effects of Nepal
.7000 schools destroyed
.widespread destruction to power, water, communications
Secondary effects of Nepal?
.Averlanch on mt Everest killed 19 people
.land triggered landslides and avalanches
.avalanche in the Lang-tan region left 250 people missing
Where was the epicentre of Nepal earthquake?
80km South West of Kathmandu
What type of plate boundary was the Nepal earthquake?
Distructive
Immediate response of Nepal earthquake?
.300,000 people migrated away from Kathmandu
.overseas aid including NGOs, Oxfam Aid form the Uk, India, China.
When was the Nepal earthquake?
25th April 2015
Long term responses to Nepal?
.Repairs to Everest base camp by August 2015
.7000 schools rebuilt or repaired
.Roads repaired and landslides cleared
