Storms Hazard

Question 1

Tropical storms

Answer 1

are intense low-pressure systems that develop in the tropics. These violent revolving storms usually measure some 200-700km in diameter.

Question 2

Deaths from storm hazards

Answer 2

Over the last 200 years, tropical storms have been responsible for around 1.9 million deaths (10,000 per year)

Question 3

Conditions required for a tropical storm

Answer 3

Sea temperatures above 27 degrees
A location of 5 degrees north or south of the equator where the coriolis affect takes place
In the Intertropical Convergence Zone (ITCZ) where warm air is forced to rise and there is atmospheric instability

Question 4

Formation of tropical storms

Answer 4

Some formation of atmospheric disturbance
Over warm seas within the tropics
Process of condensation releases latent heat
Low pressure at equator creates strong winds
As the storm spins over warm waters it continuous to gather warm moist air.
When the storm reaches land it loses energy

Question 5

Structure of a tropical storm

Answer 5

The central eye is an area 10-15km in diameter in which there are calm conditions, clear skies, higher temperatures and descending air.
The most damaging and powerful part of the storm is the ‘eye wall’
Cloud and rain then extend in a series of waves well beyond the eye wall.

Question 6

High winds

Answer 6

Average wind speeds often exceed 150km/h and can reach speeds of 250km/h in the eye wall.
Such high winds can destroy or damage buildings, roads and bridges.
They can also bring down power lines leading to electricity cuts and occasionally fires.
Agricultural land can also be devastated,and flying debris is a threat to life.

Question 7

Storms surges

Answer 7

Account for around 90% of tropical storm deaths.
A storm surge occurs when the ocean heaves upwards as a result of the low atmospheric
pressure and combines with wind-driven waves which pile up against the shore.

Question 8

Spatial distribution of tropical storms

Answer 8

Tropical storms occur between 5o and 20o north and south of the equator. Once generated, they tend to move westwards.

Question 9

Saffir-Simpson scale

Answer 9

a five-point scale based on central pressure, wind speed, storm surge and damage potential.

Question 10

Regularity and predictability of tropical storms

Answer 10

They occur between 5-20o north and south of the equator. They also mostly occur from late summer into autumn

Question 11

Social impacts of tropical storms

Answer 11

Tropical storms bring widespread flooding (primary effect) which can cause death and injury.
Damaged properties (primary effect) may lead to homelessness and the break-up of communities
governments, politicians can come under pressure and there can be unrest.

Question 12

Economic impacts of storms

Answer 12

The potential financial costs of tropical storms, to both local people and governments are high.
Damage to industries and businesses causes to loss of income and sometimes unemployment.
the cost of repairing any damage caused to buildings and infrastructure.

Question 13

Environmental impacts of tropical storms

Answer 13

Flooding can have a major impact on coastal habitats.
Flooding and mud- or landslides can also hamper the rescue effort as transport routes are often affected.