Hazardous Cram

Question 1

What are the 4 causes that can be used to categories natural hazards?

Answer 1

Tectonic & Geological

Climatic & Meteorological

Biological

Technological

Question 2

What other ways can natural hazards be categorised?

Answer 2

Magnitude- Strength/Power of event

Frequency- how often the event occurs

Size- area covered by hazard

Duration- time a hazard event lasts

Location- where it occurs

Question 3

What is a tropical cyclone?

Answer 3

Tropical cyclones are rotating, low pressure systems (below 950mb)

They are known ashurricanes, cyclonesandtyphoonsin different areas of the world

Question 4

What are the characteristics of a tropical cyclone?

Answer 4

Heavy rainfall

High wind speeds (Over 119kmph)

High waves and storm surges

Calm eye at center.

Question 5

Explain the distribution of earthquakes:

Answer 5

Earthquakes are found at all types of plate margins.
Earthquakes can occur anywhere there is a fault or weakness in the crust.
There is an ‘earthquake belt’ around the world where plate activity gives rise to earthquakes.
This belt is most noted in a circle around the Pacific Ocean, known as the Pacific Ring of Fire
Also seen in a line through the Mid Atlantic Ridge.

Question 6

What are the causes of tropical cyclone hazards?

Answer 6

Low-pressure areas (less than 950mb)
Between 5° and 20° north and south of the equator
Low wind shear
A deep layer of humid air

Question 7

What are the stages of tropical cyclone formation?

Answer 7

• Warm, moist air rapidly rises forming an area of low pressure
• Air from high-pressure areas rushes in to take the place of the rising air
• This air then rises forming a continuous flow of rising air
• As the air rises it cools and condenses. This releases heat energy which helps to power the tropical cyclone
• The Coriolis force causes the rising air to spiral around the centre.
• Some of the air sinks in the middle of the storm forming the cloudless, calm eye.
• The tropical cyclone moves westwardsfrom its source
• When a tropical cyclone makes landfall or moves over an area of cold water it no longer has a supply of warm, moist air and it loses speed and temperature. Rainfall and winds decrease

Question 8

What are the features of Tropical Cyclones?

Answer 8

Heavy rainfall
High wind speeds (over 74kmph)
Storm surges
Calm eye
Highest winds and heaviest rain the wall of the eye
Diameter up to 800km

Question 9

What is wind shear?

Answer 9

Sudden changes in wind speed and/or direction.

Question 10

What is the coriolis force?

Answer 10

The invisible force that appears to deflect the wind. The coriolis force applies to movement on rotating objects.

Question 11

What is the coriolis effect?

Answer 11

Describes the pattern of deflection taken by objects not firmly connected to the ground as they travel long distances around the earth.

Question 12

What is divergent, convergent and transform plate boundaries?

Answer 12

Divergent: Constructive
Convergent: Destructive
Transform: Conservative

Question 13

What are the primary hazards of volcanoes?

Answer 13

Ash

Pyroclastic flow

lava flow

gas emissions

volcanic bombs

Question 14

What is pyroclastic flow?

Answer 14

Clouds of superheated material up to 700 degrees centigrade which can travel up to 500kmph.

Question 15

What are the secondary hazards of volcanoes?

Answer 15

Lahars

Acidification

Landslides

Climate Change

Fires

Question 16

What are the different methods of monitoring being used to help research possible prediction methods?

Answer 16

Tiltmeters

Clusters of small earthquakes

Changes in radon gas emissions

Changes in animal behaviour

Remote sensing of ground movement using satellites

Question 17

How does risk assessment play a role in long term planning?

Answer 17

Risk assessment helps in long term planning by identifying and assessing the likelihood and consequences of potentially disastrous events.

Organizations can better prioritize resources and take preparedness actions.

Question 18

How does hazard mapping play a role in long term planning?

Answer 18

Maps the areas where earthquakes/hazardous events are most likely to occur.

Enables planning of where important services and infrastructure should be located- land use zoning.

Identifies correlation between risk and vulnerability.

Question 19

What is land use zoning?

Answer 19

Ensuring that buildings with important services, such as hospitals, are not placed in areas at high risk of natural hazards.

Question 20

How does Rebuilding Programmes play a role in long term planning?

Answer 20

• In order to minimise the impacts of collapsing buildings:
  Reducing the the number of buildings in high risk areas.
  Building earthquake resistant buildings.
• Existing buildings and structures, such as bridges can be retrofitted to make them safer in future events.