The Challenge of Natural Hazards - weather Flashcards
Hazard risk
The degree of likelihood that harm will be caused by a natural hazard.
Natural hazard
a natural event which has the potential to cause harm
Economic impact
An impact which effects the wealth of a place or some ones income.
Environmental impact
An impact which appears the natural world.
Extreme weather
When a weather event is significantly different from the average or usual weather pattern.
Global atmospheric circulation
The movement of air around the planet.
Immediate responses
A response in the days and weeks immediately after a disaster has happened.
Long-term responses
A response months or years after a disaster has happened.
Enhanced greenhouse effect
The disruption to Earth’s climate equilibrium caused by the increased concentrations of greenhouse gases has led to an increase in the global average surface temperatures.
Monitoring
Recording physical changes, such as earthquakes, tremors to help predict when/where it might strike.
Planning
Preparation for hazardous events.
Prediction
Attempts to forecast when and where a natural hazard will strike, based on knowledge.
Primary effects
The first impact of a natural event on people and property.
Protection
Actions taken before a hazard strikes to reduce its impact, such as educating people or improving building designs.
Secondary effects
The subsequent (or knock on) impacts of the primary effects which happen later.
Social impact
An impact which affects human well-being.
Mitigation
reducing causes
Adaptation
Involves adjusting to actual or expected future climate.
What is general atmospheric circulation model?
The circular movements of the Earth’s atmosphere. The circular movements of air are known as cells. These cells all join together to form the overall circulation of the Earth’s atmosphere.
Describe pressure belts
Descending air = high pressure = no clouds and rain. Rising air = low pressure = clouds and rain
Name the 3 main cells in the global atmospheric circulation model
Hadley Cell
Ferrell Cell
Polar Cell
What is high pressure and where on the global atmospheric circulation model would you find high pressure?
When air sinks towards the ground, high pressure is formed.
It happens at 30°N and 30°S of the equator, 90°N (North Pole) and 90°S (South Pole) of the equator
What is low pressure and where on the global atmospheric circulation model would you find high pressure?
When air is rising from the surface of the ground, low pressure is formed.
It happens at 0° (the equator), 60°N and 60°S of the equator
Where do surface winds blow from and to?
Winds blow from high pressure areas to low pressure areas
Describe what happens in the Hadley Cell?
Warm air rises at the equator, travels North and South and sinks around 30°N and 30°S. It then travels back to the equator
Describe what happens in the Ferrell Cell?
Warm air rises at 60°N and 60°S equator, back towards the equator. Cool air sinks at 30°N and 30°S of the equator.
Describe what happens in the Polar Cell?
Cool air descends at 90°N (north pole) and 90°S (south pole) then the air moves back towards the equator.
What is a tropical storm?
Tropical storms are also known as hurricanes, typhoons and cyclones. They are huge storms that form between the tropics.
Describe the global distribution of tropical storms
- In a band around the equator
- Within the Tropic of Cancer and Capricorn
- They are rare in the South Atlantic
Why do tropical storms form between the tropics?
The ocean temperatures are warm enough (27°C)
There is enough intense heating of the ocean to cause warm air to rise rapidly.
They don’t form directly over the equator as there isn’t enough of an impact of the earth’s rotation to cause the storm to spin so they form 5°-15° north and south of the equator.
Tropical storms in the North Atlantic region are known as?
Hurricanes
Tropical storms in south-east Asia and Australia are known as?
Cyclones
Tropical storms in Japan and the Philippines are known as?
Typhoons
What are the conditions required for a tropical storm to form?
- Warm water (above 27°C)
- Deep water
- Within the tropical zone
- No jet stream present
Which force causes tropical storms to spin?
Coriolis
How are tropical storms measured?
On the Saffir-Simpson scale of wind speeds.
Category 1: 74-95mph
Category 2: 96-110mph
Category 3: 111-129mph
Category 4: 130-156mph
Category 5: 157mph+
What are conditions like at the eye of a tropical storm?
calm
Which part of a tropical storm has the most severe winds?
eye wall
How wide can tropical storms be?
up to 300km
Describe the sequence of events when a tropical storm passes over?
- Temperature and air pressure fall
- Air pressure falls more, wind increases, lots of cumulonimbus cloud, heavy rainfall
- Calm, no wind, no rain, gets slightly warmer, air pressure still very low (EYE OF THE STORM)
- Wind and heavy rainfall increase dramatically again, temperature drops, air pressure begins to rise
- Tropical storm ends, air pressure and temperature rise
Describe the formation of a tropical storm?
- Warm wet air from the warm ocean rises. As it cools and condenses it creates huge cumulonimbus clouds.
- As the warm, wet air is rising, it creates an area of low pressure near the ocean surface. Warm air from outside the storm is sucked in to fill this ‘space’ creating a constant upwelling of warm, moist air to power the storm.
- Air leaves the spiralling column in the centre of the storm out of the top and flows downwards to the side of the storm.
Describe the features of a tropical storm?
- Up to 300 miles wide
- Wind speeds up to 252km/h and above
- Thunder and lightning, strong winds at the eye wall
Describe the primary effects of Typhoon Haiyan?
- 6,300 deaths
- 600,000 people forced to leave their homes
- 30,000 fishing boats destroyed
- 90% of city of Tacloban destroyed
- Tacloban airport severely damaged
- Infrastructure destroyed by winds
- Flooding
Describe the secondary effects of Typhoon Haiyan?
- 6 million lost jobs
- Flooding caused landslides, blocking roads meaning aid was hindered
- Power cut off
- Difficulty receiving aid as a result of damaged infrastructure
- Outbreaks of disease due to poor sanitation and shortages of shelter and water.
- Looting and violence broke out
Describe the immediate responses to Typhoon Haiyan?
- Aid agencies donated food, water and shelter quickly
- US aircrafts helped with search and rescue
- 1,200 evacuation centres were set up
- The UK provided Shelter Boxes which provided equipment to set up make-shift homes
- The Philippines Red Cross delivered basic food packages
Describe the long term responses to Typhoon Haiyan?
- Infrastructure was rebuilt e.g. bridges and airport
- Charities helped to replace fishing boats which is a crucial source of income for many citizens
- ‘Cash for Work’ programmes paid people to clean up debris
- Homes rebuilt away from flood prone areas
- Rice farming was quickly restored to ensure food production and a source of income
How are tropical storms monitored and predicted?
- Predicting the track of a tropical storm is very difficult.
- Satellite images are used to identify the distinct pattern of clouds associated with tropical storms forming over the ocean.
- Aircrafts can be used to monitor conditions within tropical storms.
- In the USA, ‘Hurricane Watch’ advises that hurricane conditions are likely. ‘Hurricane Warning’ is issued when people should take action e.g. evacuate.
How do people protect themselves from tropical storms?
Secure outdoor furniture to the ground
Cut own tree branches to avoid property damage
Window shutters
Buildings built on stilts to prevent storm surge damage
Storm drains in urban areas removed large amounts of water from storm surges
Sea walls built to hold back some water from storm surges
How do people plan for tropical storms?
Increasing citizens awareness and knowledge of what to do in the event of a tropical storm
e.g. family evacuation plans / emergency kits
Educating people on the dangers of tropical storms and how best to prepare.
How might climate change affect tropical storm distribution, frequency and intensity?
Distribution: More tropical storms may happen outside of the current areas as sea temperatures increase.
Frequency: frequency may decrease
Intensity: increase intensity of tropical storms
What kinds of weather hazards affect the UK?
Flooding
Storms
Drought
Extreme heat / cold
What causes the Beast from the east?
- a change to the northern polar jet stream, which twisted its direction unexpectedly, drawing in cold air to the UK from the east
- this bending caused by a jump in temperatures high over the Artic, known as sudden stratospheric warming
- so cold air from the Artic is dragged over to the UK, bringing severe cold weather (although the air is a lot warmer when it arrives having risen from -50 degrees
- the air picked up moisture over the North Sea bringing snow
Social impacts from the Beast from the east?
- thousands of schools were closed
- many power cuts
Environmental impacts from the Beast from the east?
- in reased amount of snow
- tempewratures below freezing throught the day
Economic impacts from the Beast from the east?
- ecnomic grew at its lowest in 6 years
- damages cost up to 1 billion pounds a day
What management/responses took place after the beast from the east?
- stranded drivers were given foil blankets
- the army were called in to help people when storm Emma hit
- the met office issued red warnings in several areas
- Public Health England urged people to plan ahead to ensure they have enough food and medicine
What evidence is there that the weather is becoming more extreme in the UK?
- all of the UK’s hottest years have been in the last 20 years
- July 2022 had record breaking temperature –> 40.3 degrees
- 10 percent wetter than a couple of decades ago
- river flooding has increased
What are the primary and secondary effects of tropical storms?
Primary:
strong winds
heavy rainfall
storm surges
Secondary:
flooding
landslides
disruption to infrastructure and livelihoods (economic, social, environmental impacts)
What are the immediate and long term responses to tropical storms?
Immediate:
rescue and evacuation
emergency services
providing aid
Long term:
rebuilding and repairing
strengthening infrastructure
improving forecasting and monitoring
economic recovery
