Challenges of natural hazards Flashcards
Describe the movement of a destructive plate margin
Two plates coming together
How can a volcano affect people
- Explosion can cause a famine due to crop damage
- Can damage houses, homelessness
- Loss of agriculture, livelihood
What are the natural causes of changes in global temperatures
- Changes in the earths orbit
- Changes in volcanic activity
- Sunspot activity
What is evidence that climate change has taken place?
- Changes in global temperature
- Sea levels rise
- More extreme weather hazards, e.g. tropical storms
- Glaciers melting
How can changes in agriculture contribute to global change in temperatures
- Increase in meat and diary production leads to increased methane released into the environment
- Changing forests into agricultural land releases greenhouse gases into the environment as trees are carbon sinks
What is our tropical storm case study?
Typhoon Haiyan
How did typhoon Haiyan affect people
6000 people died,
millions homeless
roads and infrastructure damaged
transport and communication links damaged
How did typhoon Haiyan affect the environment
storm surge
Fish killed
loss of forests
water pollution
sewage leaks
What is a natural hazard?
Extreme natural events which can cause loss of life and extreme damage to property
What are the two categories for natural hazards
Tectonic hazards
Climatic hazards
Examples of tectonic hazards
- Volcanoes
- Earthquakes
- Tsunamis
Examples of climatic hazards
- Floods
- Droughts
- Tropical storms
How do areas of contrasting wealth differ with tectonic hazards
- Preparation (buildings with retrofitting)
- developed infrastructure
- Monitoring
- Long term effects
- Money and recovery times
Why do the plates move?
- Convection currents
- Slab pull and ridge push
Where does lots of volcanic activity occur
Around the pacific ring of fire
What are the three types of plate margins
- Destructive
- Constructive
- Conservative
How are earthquakes caused
by pressuring being built up and then released, friction or plates getting stuck on eachother
sudden movements of the Earths plates
How is earthquake energy released
As seismic waves
What is prediction?
- using seismometers to monitor earth tremors
- Earthquakes are very difficult to predict when they will happen
What is protection?
- Involves constructing buildings so they are safe to live in and will not collapse
- Rubber shock absorbers in the foundations
- steel frames that sway with the earths movements
- Open areas outside of buildings for assembly points
What is preparation?
- Practise for an earthquake, in earthquake prone countries
- Drills
- Evacuation plans
- Increases chance of survival
Which plate margins do volcanos form at
- Destructive
- Constructive
What volcano forms at a destructive plate margin
A composite volcano
What volcano forms at a constructive plate margin
A shield volcano
Positive effects of a volcano
- Geothermal energy
- Ash is a good fertiliser for soil
- Attract many tourists
Negative effects of a volcano
- Dangerous to people and properties
- Economically places can suffer after eruptions
- Habitats and landscapes can be damaged by lava flow
How can volcanoes be monitored
- Seismometer
- monitoring gas escaping
- monitoring temperatures
- looking at past history of eruptions
Benefits of living by a volcano
- Fertile soil, good for crops
- Attracts tourists, good for business
- Geothermal energy, provides cheap energy for locals
- Minerals are contained in lava e.g. diamonds
What does the Global atmospheric circulation create
Wind
What are the three types of cells
Polar cell
Ferrel cell
Hadley cell
How is a tropical storm formed
- Warm water 27 degrees C, rises causing an area of low pressure
- As the air rises is draws more moist warm air up from above the ocean, leading to strong winds
- The rapidly rising air cools and condenses to form Cumulonimbus clouds
- ## These clouds form the eye wall and produce heavy rainfall
What is global warming?
The rise in average temperature of the Earths surface
What is evidence of global warming?
- Ice cores
- Glacier retreat
- Thermometer readings
- Rising sea levels
How does thermometer readings show evidence of global warming?
Show clear readings of warming of the earth other many years
How do ice cores show evidence of global warming?
A sample of ice shows the atmospheric gas concentration at the time the snow fell
How does glacier retreat show evidence of global warming?
Photos show glaciers melting and therefore retreating
Human activities which increase global warming?
- Burning fossil fuels
- Deforestation
- Agriculture
Natural factors which increase global warming?
- Orbital changes
- Volcanic activity
- Solar output
Impacts of climate change?
- Sea levels rise
- Tropical storms will increase in strength
- Species in specific areas may become extinct
- Extreme weather occurrences more often
Strategies to mitigate global warming
- Alternative energy
- Planting trees
- International agreements
