wildfires

Question 1

what is a wildfire?

Answer 1

an uncontrolled rural fire

Question 2

what is a wildfire known as in australia?

Answer 2

bushfire

Question 3

what is a wildfire known as in north america?

Answer 3

brushfire

Question 4

what is a crown fire?

Answer 4

a fire which spreads across the tree canopies and effects forested areas

Question 5

what is a groundfire?

Answer 5

a fire which burns across surface vegetation

Question 6

what is a surface fire?

Answer 6

a fire which burns below the ground in a layer of organic peat

Question 7

what is the ladder effect?

Answer 7

the process of a fire spreading from the forest floor to the canopy

Question 8

what 3 conditions are needed for an intense fire?

Answer 8

1. fuel e.g dry vegetation
2. ignition e.g lightning
3. climate conditions such as hot, windy and potentially El Nino

Question 9

What is El Nino?

Answer 9

A climate phenomenom which occurs every 6-8 years where the surface of the Pacific ocean is warmer

Question 10

how does El Nino impact fires?

Answer 10

by impacting rainfall in different areas such as leading to droughts, causing more potential fuel

Question 11

name 3 human causes of wildfires

Answer 11

1. camp fires
2. barbecues
3. falling power lines

Question 12

name 3 physical causes of wildfires

Answer 12

1. lightning strikes
2. lava
3. earthquakes (friction)

Question 13

why does fire burn up hill during the day?

Answer 13

as heat rise, drying fuel higher up on a slope

Question 14

why does fire burn downhill at night?

Answer 14

due to slope winds pushing the fire downhill

Question 15

what are slope winds?

Answer 15

winds that occur as air near the surface cools at night, sinking downward

Question 16

what are the 3 stages of wildfire growth?

Answer 16

1. preheating
2. combustion
3. glowing combustion

Question 17

what occurs during preheating?

Answer 17

water is expelled from plants due to flames, droughts or weather. Gas is then released as the temperature rises.

wood also breaks down due to pyrolisis

Question 18

what is pyrolisis?

Answer 18

the proccess of thermal decomposition of materials at elevated temperatures

Question 19

what occurs during combustion?

Answer 19

As the wood burns, gases, oils and resins are released from cracks, fueling the fire further.

Question 20

what occurs during glowing combustion?

Answer 20

wood burns at a lower temp and slower rate as fire consumes the wood itself, rather than pyrolysis gases.

Question 21

name 4 sources of fuel

Answer 21

1. loose bark e.g eucalyptus
2. pine needles
3. flashy fuels
4. new dried vegetation

Question 22

what does eucalyptus allow fire to do?

Answer 22

spread up trees

Question 23

name 3 ways to prepare for fires

Answer 23

1. emergency kits
2. warning systems to give time for evacuation
3. satellites and sensors to improve detection and monitoring

Question 24

what is deliberate burning?

Answer 24

where controlled fires are set purposefully to use up fuel before the wildfire reaches it

Question 25

what are 2 cons of deliberate burning?

Answer 25

1. time consuming 2. risks the expansion of the wildfire

Question 26

what are the pros and cons of mandatory evacuations?

Answer 26

1. people are moved to a safer area 2. casualties are limited 1. requires planning and use of resources 2. does not protect properties

Question 27

what are volunteer groups?

Answer 27

a volunteer group which removes potential fuel

Question 28

what are helicopter and aeroplane drops?

Answer 28

where an aircraft flies directly over the fire to release fire retardant and chemicals

Question 29

what are the pros and cons surrounding aircraft drops?

Answer 29

1. allows for a visual advantage 1. expensive 2. specialist pilots required 3. dangerous if flown too close

Question 30

what are smokejumpers?

Answer 30

parachuters land in the fire with axes and fire retardant

Question 31

what are the pros and cons of smokejumpers?

Answer 31

1. can land in inaccessible areas 1. risks life and injury 2. requires highly skilled people 3. can carry limited equipment

Question 32

what are wildland fire engines?

Answer 32

fire trucks which can go offroad, spraying water, foam and chemicals

Question 33

how much water can wildland fire trucks carry?

Answer 33

3000L

Question 34

what are the pros and cons of wildland fire trucks?

Answer 34

1. arrives efficiently to the scene 2. can access offroad areas 3. less expensive 1. wastes large volumes of water 2. limited water storage

Question 35

what are control barriers?

Answer 35

using natural barriers to help clear potential fuel and direct the fire path

Question 36

what are the pros and cons of control lines?

Answer 36

1. allows for prediction of the fire path 2. time consuming 3. requires many people working

Question 37

what is a flashy fuel?

Answer 37

small materials which burn faster than larger materials.