Week 1

Question 1

What is the difference between the topography of a volcano on earth and on mars

Answer 1

1. The earth’s surface is rougher as it is more dynamic - this would mean that it responds differently to the loading
2. Both mars and earth is active but the level of activity is higher on earth hence resulting in eruptions

Question 2

Why are there natural hazards on earth

Answer 2

We have physical status of water on earth. Hence, this allows for life on earth allowing the exchange of energy between different layers of the earth. This allows for the accumulation of energy.
Natural events are just different forms of energy release in a relatively short amount of time

Question 3

Why is there less temperature rise in the ocean

Answer 3

The ocean has a higher heat capacity as compared to land. Hence harder to have a big temperature change
Change can also be due to ozone

Question 4

What do you think are the reasons of COVID-19

Answer 4

Some viruses can be frozen in the ice sheets but due to global warming, the ice sheets melt and this results in an increase in viruses

Question 5

Some examples of the southeast asia ring of fire

Answer 5

Java
Sumatra
Papua New Guinea
Philippines

Question 6

What are some natural hazards near the ring of fire

Answer 6

Typhoons
Tsunamis
Earthquakes

Question 7

What has been installed in Singapore and what is it’s use

Answer 7

seismometers
Used for finding in seismic events
these are tiny events that are often missed as they are around magnitude 1-2

Question 8

Why is there an increase of hazards on earth

Answer 8

Due to an increase in the global population
Advanced science development - allows us to handle diseases better (thus we live longer)
The exponential growth of human technology allows for the growth of the human population
Geohazards are a significant challenge of living on a dynamic planet

Question 9

Catastrophes in nature

Answer 9

• everyday geologic processes produce large effects
• sudden and major impact of infrequent catastrophic events
• Disruption of temporary equilibrium between opposing influences
• Large events are part of nature and can be disastrous if they affect people

Question 10

What is a natural hazard

Answer 10

Natural process that poses threat to human life or property

Question 11

What is a natural disaster

Answer 11

Natural event that causes significant damage to life or property

Question 12

What is catastrophe

Answer 12

Natural event that kills or injures large numbers of people or causes extensive property damage

Question 13

How does size and location affect impact of disasters

Answer 13

Fewer people and buildings - little damage
Heavily populated areas - catastrophic deaths and damge

Question 14

More deaths result from…

Answer 14

Heat waves
Floods
Droughts

Question 15

Dramatic hazards occur…

Answer 15

infrequently and in restricted areas hence fewer deaths

Question 16

Why is there significant differences in fatalities from year to year

Answer 16

• rare and major events cause many deaths
• trends in leisure activities and safety measures affect fatality rate
• higher fatality rate in developing countries

Question 17

Why is there an increase in cost of natural hazards

Answer 17

• more people in path of catastrophic events
• increased value of property at risk

Question 18

Human impact of Natural disasters

Answer 18

• hydraulic fracking and wastewater disposal
• increased greenhouse gas emissions
• other human activites
• e.g effects of climate change
  1. more rapid erosion of coastlines
  2. extreme weather events causing landslides
  3. Rise in sea levels
• Development of science and technology (more data and more detailed analysis)

Question 19

What is marco scope observations

Answer 19

More than 2000 satellites recording data
allows for alot of new findings to be made

Question 20

What is micro scope observations

Answer 20

Can zoom into molecular scale and see the lvl of details and distribution of elements

Question 21

Why do we have to predict catastrophes

Answer 21

to avoid them and get them out of the way

Question 22

Why is it hard to predict catastrophes

Answer 22

• Few well documented instances of prediction
• some natural events have predictable cycles - but usually too many variables or overlapping cycles
• forecasting hazardous events might be possible in certain areas within a few decades

Question 23

Predicting catastrophe

Answer 23

• the past is the key to the future
• refinement of past recorded experiences produces statistical forecasts
  1. expressed as recurrence intervals
  2. probability that a natural event of a certain magnitude will happen within a certain period of time
  3. Not a fixed schedule for events
• Estimating the reccurance interval

Question 24

Relationship between magnitude and frequency

Answer 24

Magnitude of an event is inversely proportional to its frequency due to the conservation of energy
Hence resulting in numerous small events
Infrequent occurrence of major events makes them difficult to study

Question 25

Relationship among the events

Answer 25

Some events are directly related to each other or may overlap to reinforce each other
Past events influence future events
Some events result in more rapid changes: feedback effects

Question 26

Examples of feedback effects

Answer 26

Global warming melts artic sea ice - the darker ocean water absorbs more solar radiation than white ice causing more melting of ice
Increased cost of hydrocarbon fuels reduces usage

Question 27

Mitigation

Answer 27

• These efforts prepare for a disaster and reduce its damage

Question 28

Examples of mitigation

Answer 28

Engineering projects (leeves)
Government policies (zoning, codes)
Public education (earthquake drills)

Question 29

Land use planning

Answer 29

Find out where disasters are likely to occur and restrict development there
However these planning often come in too late
- hazardous areas are already heavily populated
- regulation often ignite intense political and legal oppositions
- restrictions are viewed as infringement of personal and property rights

Question 30

Insurance

Answer 30

To mitigate financial impact of disasters
Risk: hazard considered in light recurrence intervals and expected costs
- Greater hazards, shorter recurrence intervals - great risk
Insurance costs are actuarial, based on past experience

Question 31

The role of the government

Answer 31

Research natural and behaviors of natural disaster e.g U.S Geological Survey - studies earthquakes, volcanoes and stream flow
National weather service - monitors rainfall and severe weather
Emergency management agency - role initially to organize relief efforts, shifted to emphasizing hazard reduction
Public education

Question 32

Living with nature

Answer 32

Cannot change natural laws
attempts to control nature would only:
1. temporarily hinder natural process
2. divert damaging energy to other locations
cause energy to build up - resulting in more severe damage later
- must learn to live with nature and not to control it
- mitigation requires human behavior change