The Challenge of Natural Hazards

Question 1

A named example of a tropical storm

Example of Tropical Storm

Answer 1

Typhoon Haiyan
8th November 2013

Question 2

An example of a recent extreme weather event in the UK

Example of extreme weather in UK

Answer 2

Somerset Flooding 2014

Question 3

Named examples of tectonic hazards (in two areas of contrasting levels of wealth).

Example of tectonic hazards

Answer 3

New Zealand 2016 (GDP per capita US$40 331)
Nepal 2015 (GDP per capita US$690)
Same magnitude 7.8

Question 4

What is a natural hazard?

Answer 4

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

Question 5

What is a natural disaster?

Answer 5

A natural hazard that has actually happened.

Question 6

Outline two factors affecting hazard risk.

Answer 6

Geographical - caused by land and tectonic process
Meteorological - caused by weather and climate

Question 7

At what type of plate margin do plates move apart?

Answer 7

Constructive

Question 8

At what type of plate margin do plates move towards each other?

Answer 8

Destructive

Question 9

At what type of plate margin do plates move alongside each other?

Answer 9

Conservative

Question 10

Why do volcanoes form at destructive plate margins?

Question 11

What are the different processes causing earthquakes at conservative, constructive and destructive plate margins?

Question 12

What is the difference between a primary and a secondary effect?

Answer 12

A primary effect hazards are a direct result of the natural disaster. The secondary effect happens because of the primary effect.

Question 13

Give two primary effects of volcanic eruptions.

Answer 13

**Lava Flows **
- Layers of molten lava can destroy almost everything on their path
- trees and buildings are burnt and transport links are severed.
Can threaten whole settlements
Pyroclastic Flows
Fast moving avalanche of volcanic material (cinders, ash, pail (small stones), pumice and volcanic bombs) and hot gases
- referred to as a ‘Nuée ardente’/glowing cloud
Tephra
- Solid material of varying grain size, from volcanic bombs to ash, ejected into the atmosphere.
Volcanic gases
Variety of dangerous gases emitted:
- Hydrogen sulphide (most noticeable)
- CO2 (killed 1700 people in Cameroon, 1986)
- CO [Carbon Monoxide]

Question 14

Give two secondary effects of volcanic eruptions.

Answer 14

Landslides
Collapse of volcano flank as eruption takes place
- e.g. eruption of Mount St. Helens, 1980 - largest landslide ever witnessed
Tsunami
- oversized waves in the sea/ large lakes triggered by the collapse of volcano flanks or caldera forming volcanic events
- e.g. Santorini caldera - wiped out 80% go people at a time of great civilisation
Lahars
- Volcanic mud flows caused by the ash erupting from a volcano mixing with river water
- worst cases are when there is high rainfall/snowmelt as eruption occurs
- can occur days, weeks or years after eruption - ash layers are ‘reworked’ by heavy rain
Flooding
Melting glaciers/ ice caps can release huge quantities of water in very short periods
- Mount St. Helens, 1980 + Grimsvotn, Iceland, 1996
Climate Change
The large volumes of ash and gas ejected into the atmosphere can reduce global temperatures by blocking out sunlight.
1783 Laki eruption had a global impact which led to reduced crop yield
1991 Mt. Pinatubo - 0.5 degrees fall in mean global temperatures

Question 15

What is your example of an earthquake in a wealthy part of the world?

Example of earthquake in HIC - Kaikoura, New Zealand 2016

Answer 15

Kaikoura, New Zealand
14th November 2016
GDP $40 331
Plate boundary: Destructive and Conservative - the Pacific plate is subducting beneath the Australian plate to the north, and sliding past it to the south.
Magnitude of 7.8

Question 16

What is your example of an earthquake in a less wealthy part of the world?

Example of earthquake in LIC. - Gorkha, Nepal 2015

Answer 16

Gorkha, Nepal
25th April 2015
GDP $690
Plate boundary - destructive - the Indo-Australian plate is being subducted beneath tht eEurasian plate.
Magnitude of 7.8

Question 17

Why are the economic costs of earthquakes generally greatest in HICs?

Answer 17

The earthquakes destroy expensive buildings, meaning that rebuilding is more expensive in HICs. Wheras LICs have poor quality buildings so it wouldn’t cost too much to rebuild them.

Question 18

Whay are the human costs of earthquakes generally greatest in less wealthy places?

Answer 18

The human costs are usually lower in HIC’s because there is less deaths and less injuries due to the preparations and better quality in infrastructre.

Question 19

Why do people continue to live in places that have tectonic hazards?

Answer 19

1. Benefits That Tectonic Hazards bring
Nutrients within volcanic material - makes soil fertile - can increase income from agriculture.
Well developed tourism industry - visit famous volcanos or visit hot springs heated by geothermal activity.
2. Hazards are monitored and managed
Major advances in monitoring technology has lowered risks by detecting early signs.
Better building designs - eg. in Japan - carbon fible “curtain” on buildings to minimise the effects of shaking.
3. Infrequency of Tectonic Events
Some of the largest cities are near to tectonic hazards so people decide that it isn’t worth moving as the Natural disasters are infrequent.
4. Poverty and Education
Do not have a choice. Cannot afford to move away.
In less wealthy countries - priority is income, food, necessities - the risk of hazard is less important.
Lack of education - may not be aware its a risk.

Cheaper to live there / can’t afford to leave.

Fertile soil for farming near volcanoes.

Question 20

What are the benefits of living in a volvanic region?

Answer 20

Fertile soil for farming near volcanoes.
Geo-thermal energy - 17% of New Zealands electricity is Geo-thermal.
Raw-minerals - Sulfur, Gold, Aluminum, copper, diamonds, igneous rock.
Tourism - Millions of tourists visit every year to go up the challenging heights.
Land formation - 80% of the Earths surface has been created by volcanic erruptions.

Question 21

Give two ways that earthquakes can be prepared for.

Answer 21

1. HICs are able to invest in technology to make their buildings earthquake proof.
2. Earthquake drills to practise/prepare for an Earthquake.

Question 22

Give ways that volcanic eruptions can be predicted.

Answer 22

1. An increase in the frequency and intensity of felt earthquakes.
2. Subtle swelling of the ground surface.
3. Small changes in heat flow.

Question 23

How does global atmospheric circulation lead to high and low pressure belts?

Answer 23

Air rises at the equator, leading to low pressure and rainfall. When the air reaches the edge of the atmosphere, it cannot go any further and so it travels to the north and south. The air becomes colder and denser, and falls, creating high pressure and dry conditions at around 30° north and south of the equator.

Question 24

What are the three types of tropical storms?

Answer 24

Hurricane - USA, Latin America, The Caribbean
Cyclone - Australia (Oceania), Madagascar
Typhoon - India, Japan, The Philippines

Question 25

Describe the distribution of tropical storms.

Answer 25

Tropical storms develop between 5 and 30 degrees north and south of the equator when
- sea temp is 27+ deg celc.
- wind shear (difference in wind speed) between higher and lower parts of the atomosphere is low.

Question 26

What conditions cause tropical storms to form?

Answer 26

Temperature
Ocean temp must be around 26-27 deg celsius and at least 50m deep. Warm water provides the storm with energy.
Air pressure
Unstable air pressure - where areas of high pressure and low pressure meet - so that warm air rises more readily and clouds can form.
Wind shear
Winds must be present for the swirling motion to form - not too strong or the storm system will be ripped apart in the early stages.
Rotation
Tropical storms form between 5 - 30 deg north or south of the equation in warm oceans. Will not form on the equator.
Coriolis Effect - effect of Earth’s rotation on the weather. The storm spins beacuse the Earth is spinning. No Coriolis Effect at the equator.

Question 27

How does the intensity of a tropical storm change when it reaches land? Why?

Answer 27

Storms lose strength when they move over land or cooler water because the energy supply from the warm water is cut off.
(Energy from warm water strengthens the storm so wind speeds increase).

Question 28

Give two characteristics of the eye of a tropical storm.

Answer 28

Eye - Centre of storm - up to 50km across and caused by descending air.
- very low pressure
- light winds
- no clouds
- no rain
- high temperature.

Question 29

Give two characteristics of the eye wall of a tropical storm.

Answer 29

Surrounds the eye
- spiralling rising air
- very strong winds (around 160km/h)
- storm clouds
- torrential rain
- low temperature

Question 30

How might climate change affect the frequency, intensity and distribution of tropical storms?

Answer 30

Global average sea surface tenperatures have risen by 0.9 deg cel. since 1880 and are expected to rise more as a result of climate change.
Frequency
Oceans will stay at 27 deg cel for longer each year so there’s a longer period when a tropical storm can form so potentially more storms each year.
Intensity
Higher sea surface temperatures are likely to result in more evaporation and increased cloud formation so more energy released. This could mean they become more powerful.
Distribution
More oceans could be above 27 deg celc. - tropical storms could form in areas that haven’t experienced them before.

Question 31

List three primary effects of tropical storms.

Answer 31

Strong winds destroying buildings, infrastructure, ports
Crops destroyed
Heavy rain causing freshwater flooding
Electricity, water and communications damaged
Storm surge flattening buildings, damaging infrastructure, bringing seawater into land.

Question 32

List four secondary effects of tropical storms.

Answer 32

Food shortages
Homelessness
Loss of income as people’s livelihoods destroyed
Social disorder or conflicts
Drinking water contaminated
Spread of disease due to unhygenic conditions
Landslides and blocked roads, affecting rescue efforts
Trauma, stress and mental health issues after the event.

Question 33

For your example of a tropical storm, describe the effects of the TS.

Example of a tropical storm - Typhoon Haiyan 2013

Answer 33

Typhoon Haiyan, Philippines
8th November 2013.
Primary effects
8000+ killed
1 000 000 + homes severely damaged or destroyed
1.9 million homeless
Strong winds damaged electricity lines.
Water supplies contaminated by salt water from the storm surge
Heavy rain and storm surges flooded 600 000 hectares of farmland
Cost of damage approx. US$13 million
Secondary effects
Flooding triggered landslides - blokced roads and delayed aid.
5.6 million workers lost jobs after businesses and agricultural land destroyed.
Lack of clean water caused outbreaks of disease like dysentery.

Question 34

For your example of a tropical storm, outline the immediate and long-term responses to the TS.

Example of tropical storm - Typhoon Haiyan

Answer 34

Typhoon Haiyan, Philippines 2013
Immediate
PAGASA (Philippines’ meteorological agency) broadcast warnings about Typhoon Haiyan two days before it made landfall. This led to evacuation of 800 000 residents before the storm - unfortunately some died when evacuation centres were flooded.
Fishermen were warned not to go back to sea.
The Philippines declared a state of emergency - led to many charities offering aid - food, shelter, clean water.
Plan Internationalconstructed pit latrines for 100 000 people to help prevent the spread of disease.
Long-term
UN appealed for $300 million + to help fund rebuilding and relief.
Charities built new storm-resistant houses for those who lost their homes.
The Philippines’ tourism board encouraged people to visit the country after the storm by emphasising that most areas were unaffected and that money from tourism would help with the rebuilding process.

Question 35

For your example of a tropical storm, assess the effectiveness of the responses to the storm.

Example of tropical storm - Typhoon Haiyan

Answer 35

The Philippines and Wider World responded quickly.
Deaths were avoided - Fisherman warned and PAGASA warned re landfall
Disease avoided - pit latrines
Charities responded - food, shelter, clean water and re-built nrew storm-resistant homes.

Question 36

What types of extreme weather occur in the UK?

Answer 36

Strong winds
Heavy rainfall
Snow and Ice
Drought
Thunderstorms
Heat Waves

Question 37

What evidence exists to support the claim that weather is becoming more extreme in the UK?

Check with your notes if these details are up to date.

Answer 37

UK weather is naturally variable but extreme events are becoming more common.
Temperature
UK’s ten warmest years have occurred since 1990.
2018 joint hottest summer on record.
Extreme cold events more frequent - seven of the UKs eleven coldest temperatures have occurred since 1980. December 2010 was coldest month for over 100 years.
Rainfall
More rainfall records were broken between 2010 and 2014 than in any decade on record.
Major flooding events have become more frequent in the past 10 years - December 2015 being the wettest month ever recorded and severe flooding occured in many areas of the UK.

Question 38

What is your example of an extreme weather event in the UK?

Example of extreme weather event

Answer 38

Floods in Somerset. Winter 2013/14.

Question 39

Describe your impacts of your example.

Example of extreme weather event in the UK.

Answer 39

Impacts
* Over 600 houses flooded.
* 16 farms evacuated
* Many people had power supplies cut off
* Damages estimated to be over £10,000,000.
* 14,000 hectacres of agricultural land under water for 3-4 weeks.
* Over 1000 livestoc evacuated.
* Local roads cut off by floods.
* Floodwaters were heavily contaminated with sewage and other pollutants including oil and chemicals

Question 40

Describe the responses of your example.

Example of extreme weather event in the UK.

Answer 40

Immediate responses
* Villagers used boats to attend shcool or go shopping.
* Local community groups and volunteers gave invaluable support.

Long-term responses
* In March 2014, 8km of the Rivers Tone and Paratt were dreged to increase the capacity of the river channel.
* A £20,000,000 flood action plan has been launched by Somerset County Council who will work together with agencies such as the Environment Agency to reduce the risk of future flooding.
* Communities vulnerable to flooding will have flood defences.
* By 2024, Consideration will be given to a tidal barrage at bridgwater

Question 41

Define climate change.

Answer 41

Climate change is a long-term change in the average weather patterns that have come to define Earth’s local, regional and global climates.

Question 42

What is the Quaternary period?

Answer 42

The Quaternary Period is the third and last of the three periods of the Cenozoic Era, which began only 2.58 million years ago.

Question 43

What evidence is there to support the claim that climate change has occurred over the Quaternary period?

Answer 43

These changes can be evidenced by extracting ice cores. The glacial landscapes were dominated by ice several kilometres thick that covered all but the highest peaks in the interior.

Question 44

Which natural factors can cause climate change?

Answer 44

1. Orbital changes - image below
2. Solar output - The changes in solar energy output linked to the presence of sunspots.
3. Volcanic activity - Volcanic ash blocks the sun which reduces the temperature (short-term).

Milankovitch cycle

Question 45

Which human factors can cause climate change?

Answer 45

The greenhouse effect - trapping the sun’s warmth in a planet’s lower atmosphere. Due to the greater transparency of the atmosphere to visible radiation from the sun than to infrared radiation emitted from the planet’s surface.

Question 46

How can renewable energy technologies reduce the causes of climate change?

Answer 46

Renewable energy sources are available all around us. They are provided by the sun, wind, water, waste, and heat from the Earth. Renewable energy sources are replenished by nature and emit little to no greenhouse gases or pollutants into the air.

Question 47

List three effects of climate change on the environment.

Answer 47

1. More frequent wildfires
2. Longer periods of drought in some regions
3. An increase in the wind intensity and rainfall from tropical cyclones.

Question 48

What is a storm surge?

Answer 48

A temporary rise in water level caused by wind pushing waves onshore.

Question 49

Define a tropical storm

Answer 49

Circular in chape
Hundreds of km wide
Usually last 7-14 days
Spin anti-clockwise in northern hemisphere
Spin clockwise in southern hemisphere

Question 50

What were the primary effects of the New Zealand earthquake in 2016?

Answer 50

1. Sixty people needed emergency housing.
2. Twenty thousand buildings were damaged or destroyed.
3. Water, sewerage & power supplies were cut off.
4. Over 190 km of roads and 200 km of railway lines were destroyed
5. 2 deaths and 50 injuries.
6. Total damage is estimated at US $8.5 billion.

Question 51

What were the secondary effects of the New Zealand earthquake in 2016?

Answer 51

1. One hundred thousand landslides blocked roads and railways.
2. A landslide blocked the Clarence River, causing flooding. Ten farms were evacuated.
3. The earthquake triggered a tsunami of 5m, leaving debris up to 250 metres inland.

Question 52

What were the primary effects of the Nepal earthquake in 2015?

Answer 52

1. Nine thousand people died, and 19,000 people were injured – over 8 million people were affected.
2. Hospitals were overwhelmed.
3. Three million people were made homeless. Seven thousand schools were destroyed.
4. Electricity and water supplies, along with communications, were affected.
5. 1.4 million people needed support with access to water, food and shelter in the days and weeks after the earthquake
6. 50% of shops were destroyed, affecting supplies of food and people’s livelihoods.
7. As aid arrived, the international airport became congested.
   The cost of the earthquake was estimated to be US$5 billion.

Question 53

What were the secondary effects of the Nepal earthquake in 2015?

Answer 53

1. Avalanches and landslides were triggered by the quake, blocking rocks and hampering the relief effort.
2. Rice seed ruined, causing food shortage and income loss.
3. At least nineteen people lost their lives on Mount Everest due to avalanches.
4. Two hundred fifty people were missing in the Langtang region due to an avalanche.
5. The Kali Gandaki River was blocked by a landslide leading many people to be evacuated due to the increased risk of flooding.
6. Tourism employment and income declined.

Question 54

What were the immediate responses for the New Zealand earthquake in 2016?

Answer 54

1. A tsunami warning was issued, and residents were told to get to higher ground.
2. Two hundred vulnerable people were evacuated by helicopter.
3. Power was restored within hours.
4. International warships were sent to Kaikoura with supplies such as food, medicine and portable toilets.
5. Hundreds were housed in emergency shelters.
6. Temporary water supplies set up.
   Other countries sent food and medicine.

Question 55

What were the long-term responses for the New Zealand earthquake in 2016?

Answer 55

1. $5.3 million from the District Council for repairs and rebuilding.
2. By March 2017, a permanent water main had been laid in Kaikoura. the new pipe was designed to move with any future earthquakes so it won’t break
3. A relief fund was set up to provide basic supplies.
4. Road and rail routes reopened within two years.

Question 56

What were the immediate responses for the Nepal earthquake in 2015?

Answer 56

1. Search and rescue teams, and water and medical support arrived quickly from China, the UK and India.
2. India and China provided over $1 billion of international aid.The GIS tool “Crisis mapping” was used to coordinate the response.
3. Aid workers from charities such as the Red Cross came to help.
4. Over 100 search and rescue responders, medics and disaster and rescue experts were provided by The UK, along with three Chinook helicopters for use by the Nepali government.
5. Helicopters rescued people caught in avalanches on Mount Everest and delivered aid to villages cut off by landslides.
6. Half a million tents were provided to shelter the homeless.
7. Temporary housing was provided, including a ‘Tent city’ in Kathmandu.
8. Field hospitals were set up to take pressure off hospitals.
9. Three hundred thousand people migrated from Kathmandu to seek shelter and support from friends and family.

Question 57

What were the long-term responses for the Nepal earthquake in 2015?

Answer 57

1. A $3 million grant was provided by The Asian Development Bank (ADB) for immediate relief efforts and up to $200 million for the first phase of rehabilitation.
2. A blockade at the Indian border was cleared in late 2015, allowing better movement of fuels, medicines and construction materials.
3. Repairs were made to Everest base camp and trekking routes – by August 2015, new routes were established, and the government reopened the mountain to tourists.
4. Over 7000 schools were rebuilt.
5. Thousands of homeless people were rehoused, and damaged homes were repaired.
6. Stricter building codes were introduced.
7. Lakes that formed behind rivers damned by landslides were drained to avoid flooding.
8. Landslides were cleared, and roads were repaired.
9. Many countries donated aid. £73 million was donated by the UK (£23 million by the government and £50 million by the public). In addition to this, the UK provided 30 tonnes of humanitarian aid and eight tonnes of equipment.

Question 58

What management strategies can reduce the effects of tectonic hazards?