HAZARDS: Storm Hazards Flashcards Preview

AS/A-Level Geography > HAZARDS: Storm Hazards > Flashcards

Flashcards in HAZARDS: Storm Hazards Deck (23)
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1
Q

Tropical storms

A

Large spinning storms with strong winds + torrential rain.

2
Q

What conditions are needed for a tropical storm?

A
  • Disturbance near the sea-surfcae, eg. low pressure
  • Warm water (above 27oC to at least 50m below surface) = lots of evaporation
  • Convergence of air in lower atmosphere - forces warm air to rise
  • At least 5o from the Equator, as this is where coriolis effect is strong enough
3
Q

What are tropical storms in the Caribbean Sea called?

A

Hurricanes

4
Q

What are tropical storms in the Bay of Bengal called?

A

Cyclones

5
Q

What are tropical storms in the China sea called?

A

Typhoons

6
Q

Why do tropical storms lose strength over land?

A

Supply of warm, moist air is cut off.

7
Q

What do tropical storms initially do?

A

Move westwards due to easterly winds in tropics

8
Q

Why do tropical storms move away from the equator?

A

Due to Coriolis effect.

9
Q

How long do tropical storms usually last?

A

7-14 days

10
Q

How do tropical storms spin in the northern hemisphere?

A

Anticlockwise

11
Q

How do tropical storms spin in the southern hemisphere?

A

Clockwise

12
Q

Describe the structure of a tropical storm:

A
  • Area of low pressure at centre = eye
  • Rising air spirals around eye in the eyewall, causing strong winds
  • Outflow of moisture-laden air near top = cloud cover extends for a long distance
13
Q

How are storms classified?

A

Using the Saffir-Simpson Scale, which is based on wind speed.

14
Q

How does the Saffir-Simpson Scale work?

A
  • Rates storm hazards on a scale from 1-5 (category 5 is the strongest)
  • Estimates how much damage a storm of a given magnitude will do
15
Q

Category 5

A

Stongest storm hazard.

Winds over 250km/h

16
Q

Category 1

A

Weakest storm hazard.

Winds of 120-150km/h

17
Q

Describe the frequency of tropical storms:

A

Around 100 a year.

Northern hemisphere - June to November

Southern hemisphere - November to April

18
Q

Why can the path of a tropical storm be predicted fairly accurately?

A

Cloud formations can be identified by satellite imagery - shows formation of tropical storm.

Can then be tracked using satellites and models.

19
Q

What are some of the forms a storm hazard can take?

A

High winds

Storm surges

Heavy rain

Flooding

Landslides

20
Q

Storm surge

A

A large rise in sea level caused by high winds pushing water towards the coast, and by the low pressure of a storm.

21
Q

How can the impact of storm hazards be reduced by prevention?

A

Cannot be prevented, but can be studied to identify high-risk areas.

Future developments can be planned to avoid these.

22
Q

How can the impact of storm hazards be reduced by prepardness

A
  • Emergency services cna train + prepare for disasters
  • Evacuation routes can be planned
  • Education
23
Q

How can the impact of storm hazards be reduced by adaptation?

A
  • Buildings can be designed to withstand storms + floods
  • Flood defences can be built