Storm Hazards

Question 1

What conditions are required for a tropical storm to form?

Answer 1

• Ocean temperature above 27°C
• Depth of more than 70m
• 5° N or S of the equator for Coriolis Effect
• Area of low pressure (depression)

Question 2

What is the sequence of tropical storm formation?

Answer 2

1. Warm air rises leaving low pressure below
2. More warm air drawn in and rises
3. Warm air condenses into cumulonimbus clouds
4. Systems spins due to Coriolis Effect
5. Constant energy supply from the ocean generates higher wind speeds

Question 3

What is the eye of the storm?

Answer 3

• An area of extreme low pressure in the centre of the storm
• Characterised by calm, cloudless weather

Question 4

What is the eyewall?

Answer 4

• Surrounds the eye of the storm
• Most intense and powerful. with high winds and torrential rain

Question 5

What is storm surge?

Answer 5

• Sea level rapidly rises as the water bulges upwards and is pushed towards the coastline
• Caused due to the low pressure above the ocean

Question 6

What are the secondary hazards caused by tropical storms?

Answer 6

• Storm surge
• Coastal and river flooding
• Landslides

Question 7

What is the spatial distribution of tropical storms?

Answer 7

Located between 5° and 20° N and S of the equator (Coriolis Effect)

Question 8

How do tropical storms rotate in both Hemispheres?

Answer 8

• Northern Hemisphere = anti-clockwise
• Southern Hemisphere = clockwise

Question 9

How is tropical storm magnitude measured?

Answer 9

Saffir-Simpson Scale (1-5)
- CAT 1 = Not very intense
- CAT 5 = Very intense

Question 10

What is the frequency of storm hazards?

Answer 10

• JUN-NOV in N Hemisphere
• NOV-APR in S Hemisphere
• Intense storms are thought to be increasingly frequent

Question 11

What is the regularity of storm hazards?

Answer 11

• Occur in the same geographic areas
• Do not follow a set route

Question 12

How predictable are storm hazards?

Answer 12

• Difficult to predict
• Rapid onset
• May intensify and take an erratic path

Question 13

What are social impacts of tropical storms?

Answer 13

• Debris in high winds
• Buildings destroyed
• Homelessness
• Crop failure

Question 14

What are economic impacts of tropical storms?

Answer 14

• Businesses destroyed
• Agricultural land damaged
• Economic decline
• Rebuilding cost and insurance payouts

Question 15

What are environmental impacts of tropical storms?

Answer 15

• Beaches eroded and sand displaces
• Coastal habitats destroyed
• Coastal flooding
• Water contamination

Question 16

What are political impacts of tropical storms?

Answer 16

• Government buildings destroyed
• International aid debt
• Pressure for climate action

Question 17

What are examples of preparedness?

Answer 17

• Monitoring ocean conditions
• Weather satellites
• Evacuation plans
• Education

Question 18

What are examples of prevention?

Answer 18

• Cannot be avoided
• Climate change action

Question 19

What are examples of mitigation?

Answer 19

• Search and rescue
• Clear loose debris before storms
• Protection strategies such as drills
• Increased infrastructure resilience

Question 20

What are examples of adaptation?

Answer 20

• Land-use planning
• Move away from high risk areas
• Engineering strategies such as seawalls
• Wind-resistant buildings

Question 21

What type of buildings are at highest risk during a tropical storm?

Answer 21

Informal housing built on marginal land

Question 22

What are small-scale pressure impacting tropical storm damage?

Answer 22

• Lack of education and training
• Food insecurity

Question 23

What are large-scale pressure impacting tropical storm damage?

Answer 23

• R to U migration
• Rapid population growth
• Large outstanding debt
• Unsustainable exploitation (e.g. deforestation)