Natural Hazards
Table of Contents
Natural hazards intro........................................................................................................3
Risk and vulnerability .......................................................................................................3
Models .................................................................................................................................... 4
Degg’s model ..................................................................................................................................................4
Model of vulnerability ....................................................................................................................................5
Disaster risk equation .....................................................................................................................................5
Park Model......................................................................................................................................................5
Hazard Response Cycle ...................................................................................................................................7
Natural hazard theory ......................................................................................................8
The Earth ................................................................................................................................. 8
Theories .................................................................................................................................. 9
Tectonics ............................................................................................................................... 10
Volcanic Hazards ............................................................................................................11
Magma .................................................................................................................................. 11
Types of volcanos:.................................................................................................................. 11
Types of eruption ................................................................................................................... 12
Impacts/hazards of volcanic activity ....................................................................................... 12
Seismic hazards ..............................................................................................................13
Primary and secondary effects ............................................................................................... 14
Management ......................................................................................................................... 14
Wildfires.........................................................................................................................15
Causes ................................................................................................................................... 15
Factors................................................................................................................................... 15
Climate and recent weather ................................................................................................... 17
Management ......................................................................................................................... 17
Tropical Storms...............................................................................................................20
Formation .............................................................................................................................. 20
Hazards ................................................................................................................................. 21
Management ......................................................................................................................... 21
CASE STUDIES .................................................................................................................23
Volcanic ................................................................................................................................. 23
Nyiragongo ...................................................................................................................................................23
Eyjafjallajökull ...............................................................................................................................................25
Seismic .................................................................................................................................. 27
Haiti Earthquake 2010 7.0 .......................................................................................................27
, Christchurch ..................................................................................................................................................29
Tsunamis ............................................................................................................................... 31
Japan march ..................................................................................................................................................31
December 2004 Asian Tsunami ....................................................................................................................32
Tropical Storms ...................................................................................................................... 33
Typhoon Haiyan ............................................................................................................................................33
Hurricane Katrina..........................................................................................................................................35
Wildfires ................................................................................................................................ 38
2019-20 Australia bush fire season ..............................................................................................................38
‘Black Saturday’ Wildfire ..............................................................................................................................40
Multi-hazardous case study .................................................................................................... 41
The Philippines..............................................................................................................................................41
Case studies
Theory
,Natural hazards intro
Different types of natural events:
Natural phenomenon – a natural event that does not affect humans
Natural hazard – refers to all atmospheric, hydrologic, geologic and wildfire phenomena
that have the potential to affect humans, their structure, or their activities adversely
Natural disaster – By the UN, a hazard event must have: 10 or more deaths, 100 people
affected, a call for international assistance, declaration of a state of emergency
Types of Hazards
Geophysical – caused by earth processes
- Tsunami, earthquake, volcano, landslide/lahar
Atmospheric – processes operating in the atmosphere resulting in short-term
(meteorological) or long-term (climatological) extreme weather or conditions
- Wildfire, drought, glacial lake outburst, storm surges, typhoon, fog, extreme temperature,
hailstorm
Hydrological – caused by the occurrence, movement, and distribution of surface and
underground water
- Avalanche, flood, wave action
Risk and vulnerability
Risk: the likelihood of a hazard causing harm
Hazard: something that has the potential to harm you
Vulnerability: the level of potential for loss during, or after, a natural hazard. It can vary over
both time and space
Hazard perception: how much risk/potential we think a hazard has (as an individual)
Reasons for living in areas of risk
- Unpredictability: don’t know when/where/magnitude of the hazard
- Lack of alternatives: due to social, political, economic and cultural factors people
can’t/don’t want to leave behind their homes/land/employment
- Changing level of risk: places that were relatively safe may have become more at
risk e.g. due to climate change or deforestation which has led to more flooding
- Cost/benefit: some hazardous areas have benefits which might outweigh the risk of
the hazard e.g. Californian cities that have a risk of earthquakes
Factors that affect vulnerability
- Failing political power: when a country has an unstable government it’s hard to get
aid within the first 24hours and they might not have disaster planning
- Over-exploitation of resources: if the government has used up the resources for
other things, they might not have enough to reduce the impact of the disaster;
deforestation increases the likelihood of flooding and landslides
, - Dangerous locations: the coastline (the majority of global population lives), by active
volcanos, flat land by water, steep lands, plate boundaries.
- Disease and hunger: reduce the likelihood of surviving and makes it hard to recover
from the hazard
- War: government might have other priorities than the hazard, and they might not
accept aid if it means soldiers coming into their country
- Gender: difference in strength, different cultures have different expectations of
women (swimming)
- Age: old/young at more risk and have to rely on the working age more
- Poverty: opposite to wealth; worse diet, buildings less strong, can’t afford to move
etc
- Livelihood: e.g. farming – if crops get flooded cant earn a living and in poorer
countries you are less likely to get insurance/help from the government
- Level of available technology: more advance technology = better warning systems,
monitoring, more successful rescue efforts
- Urbanisation: if more urbanised it can cause more damage, especially in LICs where
building not built properly, and rural areas are more likely to get cut off
- Education: being able to notice the early warning signs of a hazard, knowledge of
hygiene and sanitation, school drills
Models
Degg’s model
Table of Contents
Natural hazards intro........................................................................................................3
Risk and vulnerability .......................................................................................................3
Models .................................................................................................................................... 4
Degg’s model ..................................................................................................................................................4
Model of vulnerability ....................................................................................................................................5
Disaster risk equation .....................................................................................................................................5
Park Model......................................................................................................................................................5
Hazard Response Cycle ...................................................................................................................................7
Natural hazard theory ......................................................................................................8
The Earth ................................................................................................................................. 8
Theories .................................................................................................................................. 9
Tectonics ............................................................................................................................... 10
Volcanic Hazards ............................................................................................................11
Magma .................................................................................................................................. 11
Types of volcanos:.................................................................................................................. 11
Types of eruption ................................................................................................................... 12
Impacts/hazards of volcanic activity ....................................................................................... 12
Seismic hazards ..............................................................................................................13
Primary and secondary effects ............................................................................................... 14
Management ......................................................................................................................... 14
Wildfires.........................................................................................................................15
Causes ................................................................................................................................... 15
Factors................................................................................................................................... 15
Climate and recent weather ................................................................................................... 17
Management ......................................................................................................................... 17
Tropical Storms...............................................................................................................20
Formation .............................................................................................................................. 20
Hazards ................................................................................................................................. 21
Management ......................................................................................................................... 21
CASE STUDIES .................................................................................................................23
Volcanic ................................................................................................................................. 23
Nyiragongo ...................................................................................................................................................23
Eyjafjallajökull ...............................................................................................................................................25
Seismic .................................................................................................................................. 27
Haiti Earthquake 2010 7.0 .......................................................................................................27
, Christchurch ..................................................................................................................................................29
Tsunamis ............................................................................................................................... 31
Japan march ..................................................................................................................................................31
December 2004 Asian Tsunami ....................................................................................................................32
Tropical Storms ...................................................................................................................... 33
Typhoon Haiyan ............................................................................................................................................33
Hurricane Katrina..........................................................................................................................................35
Wildfires ................................................................................................................................ 38
2019-20 Australia bush fire season ..............................................................................................................38
‘Black Saturday’ Wildfire ..............................................................................................................................40
Multi-hazardous case study .................................................................................................... 41
The Philippines..............................................................................................................................................41
Case studies
Theory
,Natural hazards intro
Different types of natural events:
Natural phenomenon – a natural event that does not affect humans
Natural hazard – refers to all atmospheric, hydrologic, geologic and wildfire phenomena
that have the potential to affect humans, their structure, or their activities adversely
Natural disaster – By the UN, a hazard event must have: 10 or more deaths, 100 people
affected, a call for international assistance, declaration of a state of emergency
Types of Hazards
Geophysical – caused by earth processes
- Tsunami, earthquake, volcano, landslide/lahar
Atmospheric – processes operating in the atmosphere resulting in short-term
(meteorological) or long-term (climatological) extreme weather or conditions
- Wildfire, drought, glacial lake outburst, storm surges, typhoon, fog, extreme temperature,
hailstorm
Hydrological – caused by the occurrence, movement, and distribution of surface and
underground water
- Avalanche, flood, wave action
Risk and vulnerability
Risk: the likelihood of a hazard causing harm
Hazard: something that has the potential to harm you
Vulnerability: the level of potential for loss during, or after, a natural hazard. It can vary over
both time and space
Hazard perception: how much risk/potential we think a hazard has (as an individual)
Reasons for living in areas of risk
- Unpredictability: don’t know when/where/magnitude of the hazard
- Lack of alternatives: due to social, political, economic and cultural factors people
can’t/don’t want to leave behind their homes/land/employment
- Changing level of risk: places that were relatively safe may have become more at
risk e.g. due to climate change or deforestation which has led to more flooding
- Cost/benefit: some hazardous areas have benefits which might outweigh the risk of
the hazard e.g. Californian cities that have a risk of earthquakes
Factors that affect vulnerability
- Failing political power: when a country has an unstable government it’s hard to get
aid within the first 24hours and they might not have disaster planning
- Over-exploitation of resources: if the government has used up the resources for
other things, they might not have enough to reduce the impact of the disaster;
deforestation increases the likelihood of flooding and landslides
, - Dangerous locations: the coastline (the majority of global population lives), by active
volcanos, flat land by water, steep lands, plate boundaries.
- Disease and hunger: reduce the likelihood of surviving and makes it hard to recover
from the hazard
- War: government might have other priorities than the hazard, and they might not
accept aid if it means soldiers coming into their country
- Gender: difference in strength, different cultures have different expectations of
women (swimming)
- Age: old/young at more risk and have to rely on the working age more
- Poverty: opposite to wealth; worse diet, buildings less strong, can’t afford to move
etc
- Livelihood: e.g. farming – if crops get flooded cant earn a living and in poorer
countries you are less likely to get insurance/help from the government
- Level of available technology: more advance technology = better warning systems,
monitoring, more successful rescue efforts
- Urbanisation: if more urbanised it can cause more damage, especially in LICs where
building not built properly, and rural areas are more likely to get cut off
- Education: being able to notice the early warning signs of a hazard, knowledge of
hygiene and sanitation, school drills
Models
Degg’s model
