🟠✅Natural Hazards - Fires In Nature

Question 1

How does vegetation type affect a wildfire

Answer 1

Determines the flammability (eg. Eucalyptus trees contain higher amounts of a flammable oil than most other trees)

Question 2

How does climate affect a wildfire

Answer 2

Continental Mediterranean climates preheat the vegetation and creates very dry conditions (40 degrees)

Question 3

How does recent weather affect a wildfire

Answer 3

If recent weather has been dry it means that the vegetation will be dry which is easier to ignite than wet vegetation / fuel.

If recent weather has been hotter it means that the fuel source will be preheated so easier to ignite.

Question 4

What conditions favour a wildfire

Answer 4

Fuel - dry leaves / green leaves / evergreen trees tend to have flammable oils (in Australia - eucalyptus trees)

Heat source - sun / lightning / cigarettes

Oxygen - atmosphere / wind

Question 5

Natural causes of wildfires

Answer 5

Lightning = heat source

Lava = heat source

Earthquakes = abrasive friction between rocks mean heats produces - release an electric charge due to Hugh pressure

Question 6

Human causes of wildfires

Answer 6

Campfire carelessness

Shooting a bullet from a gun

Trains on railway tracks can produce sparks that can start a fire

Higher tempeturs due to increased global warming as a result of human activity meaning wood is able to heat to 300C faster

Wildlife mismanagement

Broken bottles acting as a magnifying glass

Slash and burn farming techniques

Question 7

Social impacts of wildfire

Answer 7

Primary
People killed or injured in fires
Homes destroyed
People go missing due to evacuations
Evacuations

Secondary
Homelessness
Food shortages from destroyed agriculture and farmland
Health problems (asthma from smoke inhalation)

Question 8

Environmental impacts of a wildfire - air

Answer 8

Lack of visibility

Ongoing research on types of particles, the amount of particles and the damage caused by them

Controlled fires- minimise smoke and particulate dispersal

Uncontrolled wildfires- ‘out of control’ from a smoke management point of view

Smaller wildfires = less concern

Surge in CO2 due to burning

Question 9

Economic impacts of a wildfire

Answer 9

Primary
Buissnesses destroyed
Agricultural land damaged
Cost of fighting fires (fire helicopters, water)

Secondary
High cost of rebuilding and repair
Insurance payouts
Sources of income lost
Tourism decreases

Question 10

Political impacts of a wildfire

Answer 10

Primary
Government buildings destroyed

Secondary
Borrowing money for international aid
Pressure for government to do mire about global warning due to increased frequency

Question 11

Characteristic human responses to wildfires

Answer 11

Fatalism
Prediction
Adjustment / adaptations
Mitigation
Management
Risk sharing

Question 12

Issues associated with managing wildfires - climate change

Answer 12

Climate change increases average global temperature so fuel and vegetation is able to be dried out more and more rapidly and get much hotter. This increases the chance of them igniting.

Also changing weather patterns makes it harder to predict hotter days making it harder to predict when a wildfire will occur.

Question 13

Issues associated with managing wildfires - scale of the event

Answer 13

The larger the wildfire the more likely that more farmland / houses / buildings will be burnt increasing the overall damage costs and increasing the likelihood of loss of lives / injuries and loss of businesses.

Question 14

Issues associated with managing wildfires - physical characteristics of a location

Answer 14

The weather - if its hot and dry the wildfire will expands and burn more rapidly

Fuel source - type of fuel source determines the rate at which a fire will burn

Lots of fuel close together means fire spreads quickly (eg. Dense vegetation in a Forrest)

Topography - uphill burns faster as trees catch on fire as the tree below them burns

Soil type - determines the type of vegetation that grows

Question 15

Issues associated with managing wildfires - accessibility

Answer 15

Low access to supply and knowledge on how to manage and put out a wildfire can lead to a large amount of preventable wildfires and cause existing wildfires to grow.

Question 16

Issues associated with managing wildfires - government organisation

Answer 16

Remove dead leaves and branches in areas prone to wildfires.
Organise controlled burning to remove fuel.
Educate the public to reduce the human causes of wildfires.

However not all governments have the same levels of knowledge so may be unaware of what strategies are useful.
Some governments corrupt / not wealthy enough to implement these management strategies

Question 17

Issues associated with managing wildfires - community awareness

Answer 17

In Australia ‘community fire guard’ which is an education programme has been established to help individuals and communities gain high understanding of fire preparedness / resilience / prevention.
The programme focus of fire-prone and vulnerable areas and residents are taught survival strategies and techniques.

However in countries with less knowledge and poorer countries education programmes as extensive as these may be too expensive.

Question 18

What determines the nature of a hazard, its impacts and the responses?

Answer 18

The place it occurs in

Question 19

How does topography effect a wildfire

Answer 19

Wild fires move faster uphill because the flame from the top of one tree would burn the bottom of the tree above it and this provess continues.

Question 20

Environmental impacts of a wildfire - vegetation

Answer 20

Fire may injure or kill part of a plant, or the whole plant

This depends on the intensity of fire and length of exposure

Removal of vegetation can expose the soil to various elements eg heating from the sun, lack of filtration of storm water runoff, lack of soil stability and increased water flow in a rain event

Question 21

Environmental impacts of a wildfire - soil

Answer 21

Extreme heat caused by a wildfire may alter the structure of the mineral soil

If the soil is subject to intense heat then the organic matter may be killed and the structure of the soil clays.

When the soil is more sandy, high heats can cause a glass/glaze which can cause runoff from the soil

Organic matter from the soil may be ignited

Question 22

Environmental impacts of a wildfire - water

Answer 22

Potential for increased runoff of rain-fall, which may carry suspended soil particles, dissolved organic nutrients and other materials into streams and rivers and lakes that would reduce water quality.

Toxic ash may be present in water sources.

Water cycle could be disrupted - if you lose the trees you lose those specific vegetation processes (transpiration).

Question 23

Environmental impacts of a wildfire - wildlife

Answer 23

As wildlife species need food, water, cover and space the wildfire can destroy these creating spaces where they cannot thrive and grow

Larger species may be pushed away from fires while smaller animals will die from the flames and intense heat

Food chain disrupted

Question 24

Short term responses to a wildfire

Answer 24

Individual
Evacuating / dealing with short term injuries / death tolls

Government
Fire crews fighting the fires to put them out / search and rescue

Community
Search and rescue / helping

Question 25

Long term responses to a wildfire

Answer 25

Government
Rebuilding and repairing buildings and farmland / improving building regulations / learning how to prevent wildfires

Individual
Familiarisation with evacuation routes / putting together essentials bags / using fire resistant material for houses / portable air filters

Community
Develop fire survival strategies eg. local warning systems, ensuring that buffer zones are maintained, carrying out clean-ups of the local area, running equipment training sessions and preparing emergency plans.

Question 26

Preparedness and prevention - wildfires

Answer 26

Prevention
Public awareness reduces the amounst of wildfires igniting (eg Smokey the bear in the US - educates people on wildfires)

Prepare
Evacuation drills / emergency kits / warning systems saying that a fire is likely to occur so the population can prepare themselves (can be done via thermal satellite imagery)

Question 27

Mitigation - wildfires

Answer 27

Immediate
Rescue teams mitigate the effects (prevent loss of lives and injuries) by providing aid / evacuations prevent loss of lives / firefighters

Long term
Controlled burning - removal of flammable materials so less fuel is available, these burnings are strictly monitored to prevent them becoming uncontrollable
Fire breaks - gaps in trees to limit spread
Mitigating the effects on their home (fireproofing their houses)

Question 28

Prevention - wildfires

Answer 28

Individual
Keep flammable objects away from house
Removal of flammable pine needles off the lawns / houses
Tree trimming

Education / managing vegetation

Controlled burnings

Question 29

Adaptation - wildfires

Answer 29

Species of vegetation evolved to become dependent on fire to reproduce.

Measures put in fire-prone places to reduce the spread of fires to their home (35m space around home and heat resistance building materials in California)

Question 30

El Niño and La Niña - what are they?

Answer 30

El Niño (warm phase) and ​La Niña ​(cold phase) are also climatic events that are thought to affect wildfire prevalence. The effects of these phenomena vary throughout the world, but in California El Niño is thought to provide warmer, wetter seasons to grow vegetation, and La Niña’s dryer seasons create more wildfires.

Question 31

Describe how El Niña causes more wildfires

Answer 31

East winds weakened
Temperature difference is reduces and warmer waters push towards west side of SAmerica and cooler water to Australia.

Cooler waters near Australia reduces rainfall and increases temperatures.
There are reduced cyclone numbers and decreased alpine snow depths.
Increased fire damage in the South East.

Question 32

Australia 2019 bushfires - risk

Answer 32

Extremely dry and warm spring and early summer provided optimal conditions for the fire.

Heatwave country average temperature of 41.9°C.

Probability of loss high, fire prone country.

Lots of densely populated coastal settlements that are more prone to wildfires.

Question 33

Australia 2019 bushfires - vulnerability

Answer 33

Social
Densely populated towns /25.9 million people in Australian / outback population hard to reach and warn / lots of older residents, less able to evacuate by themselves / lots of under 20’s dependant on parents

Place
Eucalyptus plant oil very flammable / vulnerable to climate change / seismically active area

Biophysical
Island - prone to lots of natural disasters / coastal evacuation difficult / lots of wildlife that needs to be preserved / lots of Forests

Question 34

Australia 2019 bush fires - social impacts

Answer 34

Respiratory illness increased because of smoke, including asthma / Increased pressure on health services.

18.6 million hectares of forest and over 5,900 buildings (including 2,779 homes) had been destroyed

34 deaths

Question 35

Australia 2019 bush fires - economic impacts

Answer 35

US$70 billion (cost of repair, insurance, loss of business, 5billion dollars of food loss).

Loss of crops / soil damage which has a negative effect on the farming industry.

Question 36

Australia 2019 bush fires - environmental impacts

Answer 36

20 per cent of Australia’s forests burned / 10 million hectares of land effected.

306 million tonnes of CO2 emitted.

Increased flood risk / damage to soil structure and nutrient content.

25,000 koalas killed / Kangaroos Island following the fire there were reports of so many corpses of wild animals caught in the fire that they had to be buried in huge pits.
Injured animals were taken in and fostered by local people or sent to the mainland for treatment.

Question 37

Australia 2019 bushfires - individual responses

Answer 37

Being aware of warning systems / weather systems in areas and evacuation routes.

Designating a room in the building that can be shut off from outside air when smokey conditions prevail and using a portable air filter / preparing an essentials bag.

Creating fire proof homes / fire resistant zones

Clearing flammable materials and vegetation within 10m of buildings.

Question 38

Australia 2019 bushfires - community responses

Answer 38

Victoria (Australia), a community education programme, known as ‘Community Fireguard.’

The programme focuses on identifying the most vulnerable areas in fire-prone communities and then makes residents aware of how they can be responsible for their own safety. The residents develop their own fire survival strategies and techniques, such as local warning systems, ensuring that buffer zones are maintained, carrying out clean-ups of the local area, running equipment training sessions and preparing emergency plans.

Question 39

Australia 2019 bushfires - government responses

Answer 39

Fire crews are using a combination of aircraft and land-based equipment to fight the fires. NSW Rural Fire Service says it has about 100 aircraft in the skies every day when the fires are bad, while Victoria Country Fire Authority says it has more than 60.

Stages of emergency declares in NSW, Victoria and the capital territory.

Question 40

Australia 2019 bushfires - national responses

Answer 40

States of emergency were declared across New South Wales, Victoria and the Australian Capital Territory.

Reinforcements from all over Australia were called in to assist fighting the fires and relieve exhausted local fire crews in New South Wales.

Question 41

Australia 2019 bushfires - international responses

Answer 41

More than 500 aircraft available for firefighting.

7,000 people (army, navy, airforce, firefighters) brought into Australia.

Question 42

Australia 2019 bushfires - NGO responses

Answer 42

Firefighters, supplies and equipment from Canada, New Zealand, Singapore and the United States, among others, helped fight the fires, especially in New South Wales.

Question 43

Black Saturday bushfires

Answer 43

February/ March 2009 caused by fallen power lines.

Killed 173 people / 400+ injured / 450,000 acres of land burnt / 3,500 buildings including 2000 houses burnt down.