5.c. The exposure of people to risks and their ability to cope with tectonic hazards changes over time.

Question 1

It is projected that how many people will live on Earth by 2050? How will this affected tectonic hazard risk?

Answer 1

9.7 billion people.

As towns and cities grow, greater numbers of people and property will be at risk from tectonic hazards.

Question 2

How is hazard risk distributed? What is this particularly the case for?

Answer 2

Hazard risk is not evenly distributed spatially.

Particularly the case for geophysical hazards such as earthquakes and volcanic eruptions.

It is also the case that opportunities for reducing the risks from seismic and volcanic activity have never been greater.

Question 3

Over the last 2000 years, human populations have increased in what? Where are these located? What increased risk does this bring?

(Human population changed over last 2000 years)
(Recorded human history)
(Changes in the frequency and impacts of tectonic hazards over time)

Answer 3

Increased in number and density.

These are located mostly in cities and urban areas, being close to the coast (roughly 70%).

This generates increased tsunami hazard risks.

Question 4

Human population is projected to move closer to coasts, does this equate to a higher risk?

(Human population changed over last 2000 years)
(Recorded human history)
(Changes in the frequency and impacts of tectonic hazards over time)

Answer 4

Living close to the coast does not equate to a higher risk.

E.g. risk will differ from the south coast of UK, to the east coast of USA where there is more people at risk, so more threat.

Question 5

Technology is increasing in its ability to protect populations, reducing threats. How?

(Human population changed over last 2000 years)
(Recorded human history)
(Changes in the frequency and impacts of tectonic hazards over time)

Answer 5

More hazards are reported, may be due to an increase in knowledge.

More widespread monitoring equipment, meaning more areas can pick up e.g. earthquakes.

More people in more space (globally).

Reporting is easier and promoted - perhaps through technological advances, e.g. phone calls, social media.

Question 6

How has tectonic hazard risk changed over time?

(How and why have risks from tectonic hazards changed over time?)
(Recorded human history)
(Changes in the frequency and impacts of tectonic hazards over time)

Answer 6

The number of natural disasters has increased through time.

An increase in the frequency and magnitude of some hazards, e.g. floods and severe weather.

Question 7

Why are tectonic hazards increasing over time? Give an example.

(How and why have risks from tectonic hazards changed over time?)
(Recorded human history)
(Changes in the frequency and impacts of tectonic hazards over time)

Answer 7

Explained by the interaction of physical and human factors.

For instance, human activities such as deforestation can have a direct causative influence on hazardous events such as flooding.

Question 8

What do sceptics believe about increasing tectonic hazards?

(How and why have risks from tectonic hazards changed over time?)
(Recorded human history)
(Changes in the frequency and impacts of tectonic hazards over time)

Answer 8

Believe that measuring and reporting of events has become much more reliable over the past century.

Question 9

Compared with flood and severe weather hazards, increases in the frequencies of earthquake and volcanic hazards events are less pronounced - why?

(How and why have risks from tectonic hazards changed over time?)
(Recorded human history)
(Changes in the frequency and impacts of tectonic hazards over time)

Answer 9

This is because human factors play no role in causing earthquakes and volcanic eruptions, but have a significant bearing on the impacts of seismic and volcanic hazard events.

Question 10

Comparing Haiti (most serious earthquake), with Indonesia (most serious volcano).

(Comparisons between hazards - earthquakes and volcanoes)
(Changes in the frequency and impacts of tectonic hazards over time)

Answer 10

Both events happened in the same year.

Haiti: event caused 330,000 fatalities, very poorly developed.
Indonesia: event caused 332 fatalities, economically developing.

Damage caused in Haiti could be seen as much worse than in Indonesia, as the country is not used to being hit by earthquake events. Whereas, Indonesia has been able to mitigate against their volcanic events for years - in turn having fewer fatalities.

There are far more poorly developed rural areas in Haiti than in Indonesia, so greater risk would have been placed on the population - threatening more of the population. Compared to Haiti, Indonesia has far more thriving urban areas, and more experience with past volcanic events, that have allowed them to limited the impacts of their events.

Question 11

What are hazards? Disasters?

(Exposure and vulnerability to tectonic hazards)
(The degree of risk posed by a hazard and the probability of the hazard event occurring)

Answer 11

Events that pose risk to humans - if not it is an ‘event’.

A natural disaster refers to loss of life and widespread human and physical environment damage. All case studies from chapter 4, are examples of natural disasters.

Question 12

Natural events
Natural hazards
Natural disasters

Which is most high risk? Which is least high risk?

(Exposure and vulnerability to tectonic hazards)
(The degree of risk posed by a hazard and the probability of the hazard event occurring)

Answer 12

Natural disasters: Lower tier risk.

Natural events: Higher tier risk.

Question 13

Unlike hazard or risk, a disaster is an actual event, which usually involves loss of life and significant damage to the human and natural environments.

The scale of physical exposure to earthquake and volcanic hazards depends on factors such as…

(Exposure and vulnerability to tectonic hazards)
(The degree of risk posed by a hazard and the probability of the hazard event occurring)

Answer 13

Frequency.

Magnitude.

Specific hazards generated by earthquakes and volcanic eruptions in a place.

Number of people living in the area of risk.

Question 14

Give an example of ‘specific hazards generated by earthquakes and volcanic eruptions in a place’ as a factor affecting the scale of physical exposure to hazards.

(Exposure and vulnerability to tectonic hazards)
(The degree of risk posed by a hazard and the probability of the hazard event occurring)

Answer 14

E.g. pyroclastics greater than lava flows.

We need knowledge of past events in order to make informed decisions.

Question 15

Give an example of ‘number of people living in the area of risk’ as a factor affecting the scale of physical exposure to hazards.

(Exposure and vulnerability to tectonic hazards)
(The degree of risk posed by a hazard and the probability of the hazard event occurring)

Answer 15

E.g. Naples on the slopes of Vesuvius, the population levels have grown overtime, so exposure has increased.

Also have historic evidence of Vesuvius.

Question 16

What is event interval?

(Exposure and vulnerability to tectonic hazards)
(The degree of risk posed by a hazard and the probability of the hazard event occurring)

Answer 16

The time between 2 events of equal magnitude.

Question 17

The greater the magnitude…

(Exposure and vulnerability to tectonic hazards)
(The degree of risk posed by a hazard and the probability of the hazard event occurring)

Answer 17

…the higher the chance of death and widespread destruction.

Question 18

What is the global trend for frequency?

(Frequency)
(The hazard risk equation is place specific)

Answer 18

When magnitude increases, frequency decreases.

Question 19

What is vulnerability? What determines vulnerability?

(Vulnerability)
(The hazard risk equation is place specific)

Answer 19

Ability to withstand exposure.

Determined by physical factors and socio-economics.

Question 20

Give an example as to when small changes having significant impacts.

(Vulnerability)
(The hazard risk equation is place specific)

Answer 20

Tohoku earthquake - Fukushima Daiichi.

Demonstrating that the least vulnerable can still experience significant natural disasters.

Question 21

How well do you recover?

(Resilience)
(The hazard risk equation is place specific)

Answer 21

For example: Haiti’s resilience is very poor as they are still recovering from an earthquake 14 years ago.

Question 22

How well do individuals/ communities cope and function after a destabilising disaster?

(Resilience)
(The hazard risk equation is place specific)

Answer 22

What things would you need to cope?:
- Clean water.
- Food.
- Wider access to communication.
- Shelter.

This varies from place to place, and is hazard specific.

Question 23

Levels of resilience in response to volcanic and earthquakes is very different. Explain.

(Resilience)
(The hazard risk equation is place specific)

Answer 23

Each earthquake event is different; this being the same for volcanoes.

Measures to reduce risk?:
- Construction of earthquake proof buildings.
- Erection of sea walls in case of tsunamis.
- Diversion channels for lava flows.

• E.g. Places that have a confident resilience, like Indonesia, is due to the trust in their very deep lava divergent channels around their community villages; simple strategies like these can significantly reduce impacts from hazard events.

Question 24

What is the hazard risk equation? What does it give an indication of?

(The hazard risk equation is place specific)

Answer 24

The hazard risk equation give an indication of the hazard vulnerability for a location.

Risk = (frequency or magnitude of the hazard x level of vulnerability) / capacity of population to cope and adapt.

R = (H x V) / C

R = hazard risk
H = exposure
V = vulnerability
C = resilience

Question 25

How can volcano events be modified?

(Possible future strategies to cope with risks from tectonic hazards)

Answer 25

It is not possible for the vast majority of volcanic eruptions. However, the following have been tried with some success:
- Lava-diversion channels
- Spraying lava to cool it so it solidifies
- Slowing lava flows by dropping concrete blocks.

Earthquakes:
- Nothing can be done to modify an earthquake event.

Question 26

Outline ways to reduce people’s vulnerability to a tectonic hazard.

(Possible future strategies to cope with risks from tectonic hazards)

Answer 26

• Education.
• Community preparedness.
• Prediction and warning.
• Hazard-resistant building design.
• Hazard mapping.
• Land-use zoning.

Question 27

Outline ‘education’ as a way of reducing people’s vulnerability to a tectonic hazard.

(Possible future strategies to cope with risks from tectonic hazards)

Answer 27

Recognise signs of possible eruption:

What to do when an eruption occurs:
- E.g. evacuation routes.

Drills to practise what to do when a tectonic event strikes:
- E.g. in an earthquake, get to open space away from buildings or shelter under a table in a doorway.

Question 28

Outline ‘community preparedness’ as a way of reducing people’s vulnerability to a tectonic hazard.

(Possible future strategies to cope with risks from tectonic hazards)

Answer 28

E.g. building of tsunami shelters and walls; strengthening of public buildings - hospitals, fire stations, schools.

Question 29

Outline ‘prediction and warning’ as a way of reducing people’s vulnerability to a tectonic hazard.

(Possible future strategies to cope with risks from tectonic hazards)

Answer 29

Increasing use of technology to monitor particularly active locations, e.g. individual volcanoes.

Question 30

Outline ‘hazard-resistant building designs’ as a way of reducing people’s vulnerability to a tectonic hazard.

(Possible future strategies to cope with risks from tectonic hazards)

Answer 30

E.g. cross-bracing of buildings to support them during an earthquake; steep sloping rooves to prevent ash building up.

Question 31

Outline ‘hazard mapping’ as a way of reducing people’s vulnerability to a tectonic hazard.

(Possible future strategies to cope with risks from tectonic hazards)

Answer 31

E.g. predicted lahar routes; ground likely to liquefy in an earthquake.

Question 32

Outline ‘land-use zoning’ as a way of reducing people’s vulnerability to a tectonic hazard.

(Possible future strategies to cope with risks from tectonic hazards)

Answer 32

Land-use zoning to avoid building in locations identified by hazard mapping.

Question 33

Outline 3 ways of modifying people’s loss to a tectonic hazard.

(Possible future strategies to cope with risks from tectonic hazards)

Answer 33

Emergency aid, e.g. bottled water, medical supplies, tents, food packs.

Disaster-response teams and equipment, e.g. helicopters and heavy lifting machinery.

Search and rescue strategies.

Insurance for buildings and businesses.

Resources for rebuilding public services, e.g. schools and hospitals, and help for individuals to rebuild homes and businesses.

Question 34

What are 3 positive ways of building design?

(Building design)
(Possible future strategies to cope with risks from tectonic hazards)

Answer 34

Flat surfaces.

Steel cross frames.

Shock absorbers.

Question 35

What are 2 negative ways of building design?

(Building design)
(Possible future strategies to cope with risks from tectonic hazards)

Answer 35

Multi storey.

Location.

Question 36

Outline ‘flat surfaces’ as a positive building design method.

(Building design)
(Possible future strategies to cope with risks from tectonic hazards)

Answer 36

Reducing building density on slopes.

Construct flat surfaces.

Question 37

Outline ‘steel crossed frames’ as a positive building design method.

(Building design)
(Possible future strategies to cope with risks from tectonic hazards)

Answer 37

Imbedded within the structure of buildings.

Strengthen buildings internal structure.

Absorb tectonic energy.

Question 38

Outline ‘shock absorbers’ as a positive building design method.

(Building design)
(Possible future strategies to cope with risks from tectonic hazards)

Answer 38

Accessible to ACs such as Japan.

Constructed at the base of a building.

Absorbs horizontal energy, reducing swaying within the building.

EDCs and LIDCs do not have access to this technology, so tyres filled with stones are used.

Question 39

Outline ‘multi-storey’ as a negative building design method.

(Building design)
(Possible future strategies to cope with risks from tectonic hazards)

Answer 39

They sway at the top.

Multi storey buildings that are asymmetrical increase chances of swaying and twisting.

More susceptible to collapse.

Underground car parks and open plan office spaces weaken the structure of the building.

E.g. San Francisco, has many of these multi storey buildings with ‘soft storey’ constructions.

Question 40

Outline ‘location’ as a negative building design method.

(Building design)
(Possible future strategies to cope with risks from tectonic hazards)

Answer 40

Build as far away from fault lines as possible. This limits the severity of tectonic events.

Unconsolidated/ soft rock bases are the most at risk, e.g. alluvium (river deposits).

Avoiding slopes decreases the chances of landslides hitting buildings.

Earthquakes lead to slope failure and can trigger mass movement processes.

Question 41

Where are regulations and codes often used? What is a problem they face?

(Importance of buildings regulations and codes)
(Possible future strategies to cope with risks from tectonic hazards)

Answer 41

ACs.

Many buildings were built before the codes, so many do not fit within the regulations; this is a problem for ACs, e.g. USA.

Regulations and codes may still be ignored; this is a problem for ACs, e.g. Italy.

Question 42

Do regulations and codes exist in LIDCs and EDCs?

(Importance of buildings regulations and codes)
(Possible future strategies to cope with risks from tectonic hazards)

Answer 42

Regulations are less likely to exist.

More focused on e.g. widespread poverty, squatter settlements.

Question 43

Where are building regulations most important?

(Importance of buildings regulations and codes)
(Possible future strategies to cope with risks from tectonic hazards)

Answer 43

Hospitals, water treatment plants, and power stations.

Question 44

Why are improvements to building regulations often not dealt with?

(Importance of buildings regulations and codes)
(Possible future strategies to cope with risks from tectonic hazards)

Answer 44

Politicians focus on short-term differences to communities in order to benefit the current population, thinking less about future generations.

Long-term building design construction is not attractive to voters, as it can take decades to build.

Question 45

When a tectonic disaster strikes, what happens?

(The relationship between disaster and response)

Answer 45

Its impact often follows a sequence of stages.

Question 46

The shape of the disaster-response curve changes according to what?

(The relationship between disaster and response)

Answer 46

According to different hazards.

Question 47

The rate at which the quality of life deteriorates following a disaster will often depend on what?

(The relationship between disaster and response)

Answer 47

Will often depend on a combination of physical and human factors.

Question 48

What is the Park Model also called? What does it show?

(The Park Model (of disaster response))
(The relationship between disaster and response)

Answer 48

Also referred to as the disaster response curve.

Its aim is to show the effects of a hazard on quality of life over a sequence of time; it consists of five stages.

Question 49

Outline stage 1 of the Park Model.

(The Park Model (of disaster response))
(The relationship between disaster and response)

Answer 49

Occurs prior to the event and shows that quality of life is at its normal equilibrium level.

Question 50

Outline stage 2 of the Park Model.

(The Park Model (of disaster response))
(The relationship between disaster and response)

Answer 50

Where the hazard occurs and, again, at this point quality of life is at normal level.

Question 51

Outline stage 3 of the Park Model.

(The Park Model (of disaster response))
(The relationship between disaster and response)

Answer 51

Where the event has happened and search and rescue is underway.

Quality of life drops at this stage and stays low for several hours up to several days depending on the severity of the hazard and the level of development of the region/country.

Question 52

Outline stage 4 of the Park Model.

(The Park Model (of disaster response))
(The relationship between disaster and response)

Answer 52

Where relief strategies are underway and there is an organised programme of help.

It can take a variable amount of time, from hours and days to weeks and months to reach this stage, but quality of life improves at this time.

Question 53

Outline stage 5 of the Park Model.

(The Park Model (of disaster response))
(The relationship between disaster and response)

Answer 53

Refers to long term human response; rebuilding and restoring normality.

Quality of life returns to normal and in some cases can be higher than it was originally; especially if the repairs improve on the old infrastructure etc.