global hazards

Question 1

Ferrel cell

Answer 1

Middle cell where air flows poleward between 60° & 70° latitude.

Question 2

Hadley cell

Answer 2

Largest cell which extends from the Equator to between 30° to 40° north & south.

Question 3

Polar cell

Answer 3

Smallest & weakness cell that occurs from the poles to the Ferrel cell.

Question 4

UK Heat Wave 2003

Answer 4

The heat wave was caused by an anticyclone (areas of high pressure) that stayed in the area for most of August. This blocked any low pressure systems that normally brings cooler and rainier conditions.

Question 5

Effects (UK heat wave)

Answer 5

*People suffered from heat strokes and dehydration.
* 2000 people died from causes linked to heatwave.
* Rail network disrupted and crop yields were low.

Question 6

Management (UK heat wave)

Answer 6

*The NHS and media gave guidance to the public.
* Limitations placed on water use (hose pipe ban).
* Speed limits imposed on trains and government created ‘heatwave plan’.

Question 7

Typhoon Haiyan 2013

Answer 7

Started as a tropical depression on 2rd November 2013 and gained strength. Became a Category 5 “super typhoon”.

Question 8

Effects (Typhoon Haiyan)

Answer 8

*Almost 4,000 deaths.
* 130,000 homes destroyed
* Water and sewerage systems destroyed caused diseases.
* Emotional grief for lost ones.

Question 9

Management (Typhoon Haiyan)

Answer 9

• The UN raised £190m in aid.
• USA & UK sent helicopter carrier ships deliver aid remote areas.
• Education on typhoon preparedness.

Question 10

Shield Volcano

Answer 10

Made of basaltic rock and form gently sloping cones from
layers of runny lava.
Location: hot spots and constructive margins.
Eruptions: gentle and predictable

Question 11

Composite Volcano

Answer 11

Most common type found on land. Created by layers of ash
and lava.
Location: Destructive margins
Eruptions: explosive and unpredictable due to the build of
pressure within the magma chamber.

Question 12

Hotspots

Answer 12

These happen away from any plate boundaries. They occur
because a plume of magma rises to eat into the plate above.
Where lava breaks through to the surface, active volcanoes
can occur above the hot spot. E.g. Hawaii.

Question 13

Nepal Earthquake, 2015

Answer 13

• The Indian and Eurasian plates move together at a collision plate boundary.
• On 25th April 2015, a shallow focus (15km deep) earthquake took place measuring 7.8 on the Richter Scale.

Question 14

Effects (Nepal Earthquake)

Answer 14

*8635 people were killed
*19,009 people were injured
*Historical and religious buildings were destroyed
*Schools, health facilities and government offices had to close
*Landslides buried rural villages

Question 15

Management (Nepal Earthquake)

Answer 15

*There was little warning due to the wealth of Nepal and difficulty in predicting earthquakes.
*NGOs and governments donated emergency short term aid eg. India donated blankets, water, doctors and food.
*Long term – ‘cash for work’ schemes were set up to rebuild communities and provide money.

Question 16

Destructive Plate Margin

Answer 16

When the denser oceanic plate subducts beneath the continental plate in a process called subduction. At the point of collision, the oceanic plate bends and a deep ocean trench is formed. The continental plate buckles, creating fold mountains. As the plates drag against eachother, and crack and fold, earthquakes are triggered. As the oceanic plate subducts into the hot mantle, the water helps it to melt. The water make the melted mantle less dense, so it may rise up through cracks in the continenalt plate as volanic eruptions.

Question 17

Constructive Plate Margin

Answer 17

Here two plates are moving apart causing new magma to
reach the surface through the gap. Volcanoes formed along this crack cause a submarine mountain range such as those in the Mid Atlantic Ridge.

Question 18

Conservative Plate Margin

Answer 18

A conservative plate boundary occurs where plates slide
past each other in opposite directions, or in the same direction but at different speeds. This is responsible for earthquakes such as the ones happening along the San Andreas Fault, USA.

Question 19

Collision Plate Margin

Answer 19

Collision zones form when two continental plates collide. Neither plate is forced under the other, and so both are forced up and form fold mountains. These zones are responsible for shallow earthquakes in the Himalayas.

Question 20

Causes of Earthquakes

Answer 20

Earthquakes are caused when two plates become locked causing friction to build up. From this stress, the pressure will eventually be released, triggering the plates to move into a new position. This movement causes energy in the form of seismic waves, to travel from the focus towards the epicentre. As a result, the crust vibrates triggering an earthquake.

Question 21

Shallow Focus

Answer 21

-Usually small and common.
-Seismic waves spread and damage wide area.

Question 22

Deep Focus

Answer 22

-Occur on destructive margins.
-Damage is localised as seismic waves travel vertically.

Question 23

Mercalli Scale

Answer 23

Measures how much damage is caused, based on observations, not scientific instruments.

Question 24

Richter Scale

Answer 24

Is a scientific measurement based on the energy released.