The challenge of natural hazards

Question 1

What are the conditions required for a tropical storm?

Answer 1

Warm ocean waters - 26.5°C
They usually form between 5° and 30° latitude

Question 2

How do tropical storms form?

Answer 2

The high temperatures causes the sea and air to heat to higher temperatures. Air pressure is low and air rises. The warm ocean provides heat and moisture so warm air rises rapidly. Wind is constant and doesn’t vary so clouds rise to high altitudes. Constant warm air causes low pressure and rising air.

Question 3

What is the structure of a tropical storm?

Answer 3

The eye - central part, it is an area of calm light winds with no rain with clouds forming as moist air condenses as it rises

Question 4

How can climate change affect tropical storms?

Answer 4

More oceans may be above 27 degrees, causing more tropical storms to form worldwide. A warmer atmosphere means more moisture in the air so rainfall increases, causing more destructive tropical storms and floods. Increasing sea levels mean storm surges become higher. Higher temperatures cause higher intensity storms with higher speeds.

Question 5

(CASE STUDY) What were the primary effects of typhoon Haiyan?

Answer 5

-Wind speeds of 314km/h caused the destruction of 90% of Tacloban.
-6300 deaths
-29000 injuries
-1.1 million houses damaged

Question 6

(CASE STUDY) What were the secondary effects of typhoon Haiyan?

Answer 6

-Eight deaths in a stampede for food supplies
-Flooding caused landslides
-Rice prices raised 12% by 2014

Question 7

(CASE STUDY) What were the immediate responses of typhoon Haiyan?

Answer 7

-Over 1200 evacuation centres set up to help homeless
-Over 1.5 billion dollars of foreign aid pledged with rescue operations
-One million food packs and 250,000 litres of water distributed within 2 weeks

Question 8

(CASE STUDY) What were the long-term responses of typhoon Haiyan?

Answer 8

-Cash for work programme to clear debris and rebuild Tacloban
-Oxfam replaced fishing boats
-Build back better introduced to upgrade damaged buildings for protection against future disasters
-New storm surge warning system

Question 9

What is a natural hazard?

Answer 9

A natural process which can cause death, injury or disruption to humans or destroy property and possessions

Question 10

What is a natural disaster?

Answer 10

A natural disaster is a natural hazard that has occured

Question 11

What are the types of natural hazards?

Answer 11

-Geological hazards - caused by land and tectonic hazards eg volcanoes
-Meteorological hazards - caused by weather and climate eg tropical storms

Question 12

Primary vs Secondary effects

Answer 12

Primary - Immediate eg deaths
Secondary - Later as a result eg disease spreading

Question 13

What are the 2 types of Earth crust/plates?

Answer 13

Oceanic - greater density, thinner and less buoyancy
Continental - lower density, thicker and older

Question 14

What happens at a destructive/convergent plate boundary?

Answer 14

A continental and oceanic plate move towards each other and the oceanic plate is subducted under the continental plate. The friction created causes earthquakes and/or volcanic eruptions. This can form composite volcanoes and ocean trenches

Question 15

What happens at a constructive/divergent plate boundary?

Answer 15

Two plates move apart from each other, causing magma from the mantle to rise and construct new crust or shield volcanoes. The movement of the plates over the mantle can also cause earthquakes. This can form shield volcanoes

Question 16

What happens at a conservative plate boundary?

Answer 16

The plates slide past each other in opposite directions or in the same direction but at different speeds. As the plates move past each other, friction occurs and the plates become stuck. Then when the energy is released (as seismic waves) it causes an earthquake. No volcanoes form at a conservative plate boundary

Question 17

What happens at a collision plate boundary?

Answer 17

Two continental plates collide and neither can be subducted so the land buckles upwards to form fold mountains. Earthquakes can occur here

Question 18

Why do people live near plate boundaries?

Answer 18

-Opportunities for tourism
-Gives valuable minerals and materials
-Geothermal energy source
-High soil fertility

Question 19

What is the global atmospheric circulation?

Answer 19

The transfer of heat from the equator to the poles by the movement of air (how air moves around the world)

Question 20

Why does the air around the world move?

Answer 20

Due to difference in pressure - wind blows from high pressure to low pressure

Question 21

What causes high and low air pressure?

Answer 21

High pressure - when cool air descends
low pressure - when warm air ascends

Question 22

How does global atmospheric circulation work?

Answer 22

Due to high temps at the equator, air rises into the atmosphere causing low pressure. The air then condensed to form clouds leading to rainfall, hence why tropical rainforests are found along the equator

Question 23

What are the points of an earthquake

Answer 23

Focus - the point in the Earth where the earthquake starts
Epicentre - the point directly above the focus on the Earth’s surface
Seismic waves - vibrations from the earthquake which are strongest near the epicentre

Question 24

How are earthquakes measured?

Answer 24

Richter scale - magnitude/force of the earthquake using seismometers
Mercalli - intensity of an earthquake and its effects in a given area

Question 25

What factors affect risk of a hazard?

Answer 25

Development - HICs are better equipped to cope with natural hazards than LICs due to better infrastructure, emergency responses and monitoring for predicting hazards as well as better healthcare Climate change - magnitude and frequency of some climatic hazards such as droughts and tropical storms, is affected by climate change

Question 26

(CASE STUDY) What caused the Christchurch (HIC) 2011 earthquake?

Answer 26

Conservative plate boundary (slide along eachother and cause friction) between pacific plate and Australian plate. It was a 6.3 on the Richter scale

Question 27

(CASE STUDY) What were the primary impacts of the Christchurch earthquake?

Answer 27

-(social) 185 deaths, over 6000 injuries, cathedral spire collapsed -(economic) $28 billion worth of damage -(environmental) soil liquefaction and surface flooding

Question 28

(CASE STUDY) What were the secondary impacts of the Christchurch earthquake?

Answer 28

(social) over 40% of Christchurch without power at the height of the impact (economic) roads and bridges were damaged so less people could get to work, as well as businesses such as the Canterbury television building collapsing. Tourism dropped by around 30% in the year following. (environmental) 400000 tons of silt deposited onto the land due to liquefaction, rendering land uninhabitable

Question 29

(CASE STUDY) What were the Immediate responses to the Christchurch earthquake?

Answer 29

-Over 500 rescue workers deployed from New Zealand and internationally such as from Australia -300 police officers flew in from Australia 3 days later -Over 300 people pulled from rubble -$6 to 7 million of international aid provided -30,000 residents provided with chemical toilets

Question 30

(CASE STUDY) What were the long-term responses to the Christchurch earthquake?

Answer 30

-Construction of 10000 affordable houses -Water and sewage restored by August -Temporary housing provided by government

Question 31

(CASE STUDY) What caused the Haiti earthquake 2010?

Answer 31

Conservative plate boundary (slide past each other) of the Caribbean plate and the North American plate. It had a magnitude of 7 on the Richter scale

Question 32

(CASE STUDY) What were the primary impacts of the Haiti earthquake?

Answer 32

(Social) 230,000 deaths (economic) $8 billion in damage which was 120% of Haiti's GDP at the time (environmental) massive landslides

Question 33

(CASE STUDY) What were the secondary impacts of the Haiti earthquake?

Answer 33

(Social) 2 million people without food or water, 10,000 deaths from cholera outbreak (economic) 5.1% decrease in GDP following year, millions of dollars in tax revenue lost due to destruction of buildings (environmental) 11 million cubic meters of rubble and waste in streets, blocking drainage

Question 34

(CASE STUDY) What were the immediate responses to the Haiti earthquake?

Answer 34

-Slow help due to damaged port -USA sent 10,000 troops -235,000 moved away from Port au Prince to less damaged cities

Question 35

(CASE STUDY) What were the long-term responses to the Haiti earthquake?

Answer 35

-New homes built to higher standard, over 200,000 houses built or repaired by 2014 -$1.2 billion in debt forgiven -Over 2,000 schools rebuilt

Question 36

What is monitoring?

Answer 36

Recording physical changes, such as earthquake tremors, to help forecast where and when a natural hazard might occur

Question 37

What is prediction?

Answer 37

Attempts to forecast where and when a hazard might occur based on current knowledge (is less reliable for earthquakes)

Question 38

What is protection?

Answer 38

Actions taken before a hazard strikes to reduce its impact, such as improving building design

Question 39

What is planning?

Answer 39

Actions taken to enable communities to respond to and recover from natural disasters through evacuation plans and warning systems etc

Question 40

Why are deserts found along 30 degrees north and south of the equator? (global atmospheric circulation)

Answer 40

When air rises and reaches top of atmosphere, it must move somewhere and so travels north and south of equator. The air then cools around 30 degrees north/south of equator and sinks, creating high pressure. As moisture is dry, few clouds form, hence why deserts are found.

Question 41

What is extreme weather?

Answer 41

Weather that is unexpected and out of season

Question 42

(CASE STUDY) What caused the Beast from the East?

Answer 42

Stratospheric warming caused the jet stream to weaken, leading to a change in the direction of winds approaching the UK from west to east to east to west, allowing polar continental air mass from Russia to cover the UK. When it reached the UK it was just below freezing

Question 43

What were primary impacts of the Beast from the East?

Answer 43

(social) 10 people died, rural areas snowed in (economic) roads shut and over 1,000 flights cancelled causing many businesses to shut and people could not get into work, causing a loss of sales (environmental) high levels of flooding as snow melted causing rivers to overflow

Question 44

What were secondary impacts of the Beast from the East?

Answer 44

-Thousands of schools closed -Shortage of food in supermarkets -Drifting snow led to rural villages being isolated

Question 45

What were some responses to the Beast from the East?

Answer 45

-Red weather warnings issued -10 RAF vehicles transported doctors and stranded patients -Volunteers gave supplies to those stranded in traffic

Question 46

What evidence is there that weather is becoming more extreme?

Answer 46

2022 was record-warm 6% below avg rainfall in 2022 Sea levels rising 18.5cm since 1990s Recent decade has been 0.3 degrees warmer on avg than previous decade

Question 47

How do ice cores show changes in climate change?

Answer 47

Sample taken from glacier can be analysed for gasses from each year to gather information on up to 5 million years ago

Question 48

What are some natural factors for climate change?

Answer 48

Volcanic activity - volcanic cooling caused when particles released from eruptions (sulphur dioxide) reflect sunlight Orbital changes Sun spots (hotter areas of the sun)

Question 48

What is eccentricity?

Answer 48

Eccentricity - The shape of the Earth's orbit changes over around 100,000 years from round to elliptical

Question 49

What is axial tilt?

Answer 49

Axial tilt - The angle of the Earth's axis changes over 41,000 years

Question 50

What is precession?

Answer 50

The wobble of the Earth's axis influencing timing of seasons